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PROPERTY OF THE "~~. NATIONAL ZOOLOGICAL PARK

pROPERT 8 OC NATIONAL ooLoste

AL PARE

Py) Wena ee " “at Plt * Wa Abies

: ny (ae

°

<> PROCEEDINGS

OF THE

SCIENTIFIC MEETINGS

OF THE

ZOOLOGICAL SOCIETY OF LONDON

FOR THE YEAR

1876.

OPERTY OF THE NATIONAL Oe PARE

PRINTED FOR THE SOCIETY, AND SOLD AT THEIR HOUSE IN HANOVER SQUARE. LONDON:

MESSRS. LONGMANS, GREEN, READER, AND DYER, PATERNOSTER ROW,

te Kiss ed &

OF THE

COUNCIL AND OFFICERS

OF THE

ZOOLOGICAL

SOCIETY OF LONDON.

1876.

COUNCIL.

THe Marauis oF Twreppan, F.R.S., President.

THE Lorp ABINGER.

Tut Lorp CaLrHorPE.

Masor-Gen. Henry Crerk, R.A., FR.S:

Rosgert Drummonp, Esq., Z'rea- surer.

Proressor Frower, F.R.S., Vice- President.

Joun P. Gasstorr, Jun., Esq.

Artuur Grote, Esq.

Dr. AtBert GintHER, F.R.S., Vice-President.

Dr. E. Haminton, Vice-President.

Epmunp W. H. Hotpsworra, Esq.

Rosert Hvpson, Esq., F.RS., Vice-President.

Proressor Mivart, F.R.S.

Proressor Newton, F.R.S., Vice- President.

| Henry Potrock, Esq.

THE Lorp Anruvur Russett, M.P. OsseErt Satvin, Esq., F.R.S. Painie Lourie, Scrater, Esq., M.A., Pu.D., F.R.S., Secretary. Ricwarp H. 8. Vyvyan, Esq. Tur Lorp WALSINGHAM. Grorcr R. Waternouse, Esq., Vice-President.

PRINCIPAL OFFICERS. Office, 11 Hanover Square, W.

P. L. Scuater, Esq., Ph.D., F.R.S., Secretary. Mr. F. H. Warernovuse, Librarian. Mr. W. J. WitttaMms, Clerk.

Gardens, Regent's Park, N.W. Mr. A. D. Bartierr, Superintendent. Proressor Garrop, F.R.S., Prosector

<p

Gist

OF THE

CON TRIBU LORS,

With References to the several Articles contributed by each.

Apams, Henry, F.L.S., and Ancas, Georcre Frenca, F.L.S., C.M.Z.S.

Descriptions of five new Species of Land-Sheils from Mada- gascar, New Guinea, Central Australia, and the Solomon sland st Cblate Doin ViE Le cis cient rave wid) asec uareaie ig tia akon s

Auston, Epwarp R., F.G.S., F.Z.S. On the Classification of the Order Glires. (Plate IV.) .. On the Genus Dasyprocta; with Description of a new SPecleser snk ALG: A MUNG). appar Merete srs ae, titel cl gbesemn cre

On two new Species of Hesperomys..........

ANDERSON, ANDREW, F.Z.S.

Corrections of, and Additions to ‘ Raptorial Birds of North-western India.””— Part II. (Plate XXIII.)........

Exhibition of a coloured drawing of Hmys hamiltonii.. .

Corrections of, and Additions to the “ Raptorial Birds of North-western India.’ Part III. (Plate LX XXII.)

Page

488

iv

Page Aneas, Grorce Frencu, F.L.S., C.M.Z.S.

Descriptions of Four new Species of Helix ; with some

Notes on Helix angasiana of Pfeiffer. (Plate XX.) ...... 265 AnGas, Grorce Frencu, F.L.S., C.M.Z.S., and Apams Henry, F.L.S.

Descriptions of five new Species of Land-Shells from Ma- dagascar, New Guinea, Central Australia, and the Solomon islands: “(Plate MLVIL.)) Si. oe. eses ee) eee mee

BarTLeTT, Epwarp, and Druce, Hersert, F.L.S., F.Z.8.

List of the Butterflies of Peru, with Descriptions of new

Species. sblates! XV PL XV LT es ie so. ateue olan toratentes 205 Beppomg, Lieut.-Col. R.H., C.M.Z.S8.

Description of a new Species of Indian Snake of the Genus

Piatyplectrurus tromethe: Wynad 2, sio% i. spelste s1:1ee cielo eiaeae%e 701

Be.t, F. Jerrrey, Exhibitioner of Magdalen College, Oxford.

Notes on the Myology of the Limbs of Moschus moschiferus 182

Bennett, Dr. Grorce, F.Z.S.

Wetter fro mits cit ets Ac esas ee ee ee LG

Buanrorp, W. T., Assoc. Roy. Sch. Min., F.R.S., F.G.S., F.Z.S.

Note on the ‘ Africa-Indien’ of A. von Pelzeln, and on the Mammalian’ Fauna of Tibet “2. 2... «2. 0 ase eee oe 631

On some of the Specific Identifications in Dr. Giinther’s Second Report on Collections of Indian Reptiles obtained by the BritishoMiusetn a5..;¢: 2c... ee. tie oe « See

BoweERBANK, JAMEs Scort, LL.D., F.R.S., F.Z.S.

A Monograph of the Siliceo-fibrous Sponges.—Part VI. (Plates LVIi:& LVI) it room dese che atest ot as eeeedete ee 00D

Contributions to a General History of the Spongiade.— Part VII. » (Plates LXAMVITTALX XXL) ie bec seam (708

Vv

Page

Brooke, Sir Vicror, Bart., F.Z.S8. Supplementary Notes on Cervus mesopotamicus .......-- 298 On: Cervus-schomburght (Blyth) 0. csice. Gece sie o ses 304

Brown, Rev. Grorce, C.M.Z.S.

Letter from, on birds transmitted to the Society from Duke-of YOre Isianaty oy sctsen.s tos aferrsee wating eeewhe 2

Buckiey, T. E., .B-A:, F:Z.8.

On the past and present Geographical Distribution of the Iharge Mammals: of, South Agric ... cio viesa si oeiss 90 po acess 277

BurMEISTER, HERMANN, Director of the National Museum, Buenos Aires, F.M.Z.S.

Additional Notes on Dolichotis salinicola ........00-- 461

Busk, GrorGe, F.R.S., F.Z.S.

Notice of a Memoir on the Ancient or Quaternary Fauna of Gibraltar, to be published in the Society’s ‘Transactions’ 415

Butter, ARTHUR GARDINER, F.L.S., F.Z.S., Assistant, Zoo- logical Department, British Museum.

Revision of the Lepidopterous Genus Teracolus, with De- scriptions of the new Species. (Plates VI. & VII.) ...... 126

On a small Collection of Butterflies from the New Hebrides 251

Descriptions of Lepidoptera from the Collection of Lieut. Howland Roberts. (Plate XXII.) ............ Sartre she 308

Descriptions of new Species of Lepidoptera from New Guinea, with notice of anew Genus. (Plate LXXVII.) .. 765

CampripGe, Rev. O. Pickarp, M.A., C.M.Z.S., Hon. Mem. New-Zealand Institute.

On a new Order and some new Genera of Arachnida from Kerguelen’s Land. (Plate XIX.)

ho or DM

vi Page Catalogue of a Collection of Spiders made in Egypt, with Descriptions of new Species and Characters of a new Genus.

(Plates TiVILE EX) iitraaes sotsiesla cee eaten 54} Cuark, J. W., M.A., F.Z.S. Notes on a Dolphin taken off the Coast of Norfolk. (Plates XIV: & LXV...) a clas 2% Ws ie's.sks aie Se Oe stegetereners 686

Cosson, T. Seencer, M.D., F.R.S., F.L.S., Correspondent of the Academy of Sciences of Philadelphia.

Notes on Entozoa.—Part III. (Plate XVI.) ........ 200 Exhibition of and remarks on a parasite (2chinorhynchus). 256

Notes on Entozoa.—Part IV. (Plate XXI.) ........ 294

Comrig, Dr. P.

Exhibition of, and remarks on, zoological specimens col- lected during the survey, by H.M.S. ‘ Basilisk,’ of the 8.E. Goastrol NewasGiine ass 02i..5 leah iain ted os isis eee te pete wee 422

Cooxson, Commander W. E., R.N.

Letter from, containing remarks on the Tortoises of the Gala ae Os Ue i parai mr snaph svete conta acetate ote Unave eieks eye crete eteee 520

Cunnincuam, D. J., M.B., Demonstrator of Anatomy, Uni- versity of Edinburgh.

Description of a young Specimen of the Delphinus albi- rostres. iP late dais) cs t,0% ste oe eiuas eect ate eee: Od

D’Avsertis, Luic1 Maria, C.M.Z.S8.

Letter from: ‘Hayes elie Skis Ge by aided ere aie eee 519 Day, Surgeon-Major Francis, F.Z.8. &c.

On the Fishes of Yarkand ........ iB ine$,c Saves ees 781 Dosson, G. E., M.A., M.B., F.L.S., C.M.Z.S., &c.

On Uystacina.tuberculata dt i. .site «bss vtiiited vietere 486

vil

On peculiar Structures in the Feet of certain Species of Mammals which enable them to walk on smooth perpendi- cular surfaces. (Plate LV.)........

A Monograph of the Group Molosst ...........+.04. ‘Dresser, Henry E., F.ZS.

Remarks on a Hybrid between the Black Grouse and the Hazel Grouse......

On a new Species of Broad-billed Sandpiper ........ On a new Species of Tetraogallus...... Druce, HEersBert, F.L.S., F.Z.S., and BartLett, Epwarp,

Curator of the Museum and Public Library, Maid- stone.

List of the Butterflies of Peru, with Descriptions of new SMecien.-, quelabes 6 V (ede eV LL.) Vos See cw bieed auie we

Drummonp, W. H.

On the African Rhinoceroses.. ............

Duncan, Professor P. Martin, F.R.S., Pres. G.S.

Notice of the second part of his Memoir on the Madrepo- raria dredged up during the Expedition of H.M.S. ‘ Porcu- pines in, T8692 70. says. <i tins Bewley aye awa oh ees sue

Notices of some Deep-sea and Littoral Corals from the

Atlantic Ocean, Caribbean, Indian, New-Zealand, Persian Gulf, and Japanese, &c. Seas. (Plates XXXVIII.-XLI.)..

FerGuson, Wiiu1aM, F.L.S.

Description of a New Snake of the Genus Aspidura from

Ceylon ia eis dts acid vita ate ards os! Fx idle er Haas! Waioraeeterens

Finscu, Orro, Ph.D., C.M.Z.S. &c., Curator of the Bremen

Museum.

Notes on some Fijian Birds, including Description of a new Genus and Species .............

Letter from, containing remarks on the supposed existence

of the Wild Camel in Central Asia .........

205

109

424

819

1g

.. 696

Vill

Fiowrer, WittiamM Henry, F.R.S., F.L.S., V.P.Z.S., Con- servator of the Museum of the Royal College of Sur- geons, and Hunterian Professor.

Description of the Skull of a Species of Xiphodon, Cuvier. (BlatesE.)it..< Soames

On some Cranial and Dental Characters of the existing Species of Rhinoceroses .......-..-- day's die dela

Remarks upon Dr. von Haast’s Communication on Ziphius NOUE=2CULANAEE. 1.5 5 careulereleie eee cts erehee)* ev efies = etelete fetal:

Remarks upon Dr. von Haast’s Communication on Mesop- LOOM LOWETE 608. cidciah ac a Ctins 6G nts lela our nie sofa = = eee rene

Garrop, Atrrep Henry, B.A., F.Z.S., Fellow of St. John’s College, Cambridge, Prosector to the Society.

On the Cecum Coli of the Capybara (Hydrocherus capy- bara)

- eee eer eee es oor ew eeosr se CF ooo eH Ee Heo we Oe ew ee oO @

On a Peculiarity in the Carotid Arteries, and other Points in the Anatomy, of the Ground-Hornbill (Bucorvus abyssi-

On the Anatomy of Chauna derbiana, and on the Systematic Position of the Screamers (Palamedeide). (Plates XII.— XV.)

ec ew ot ees eww ee Oo eo eee eo eea ers OF FFF Foo oOR Hoe He rE

On the Anatomy of Aramus scolopaceus ......

Notes on the Anatomy of Plotus anhinga. (Plates MOVES XVI ink cosets ees

Notes on the Anatomy of the Colies (Colius)

cere ee ewes

On some Anatomical Characters which bear upon the Major Divisions of the Passerine Birds.—Part I. (Plates DELV ITE LES) 24) si2e singe erence

Notes on the Anatomy of certain Parrots

On the Chinese Deer named Lophotragus michianus by Mr. Swinhoe: “(Plate XX VIE) ons 6 hone ae

Page

485

26

60

ix Grote, Artuur, F.L.S., F.Z.S.

Exhibition of and remarks upon the original drawing, by Colonel Gordon, from which the Plate of Ovis polii in the ‘Proceedings’ (1874, plate L111.) was prepared ..........

Gintuer, Augert, M.D., Ph.D., F.R.S., V.P.Z.8., Keeper of the Zoological Department, British Museum.

Exhibition of specimens of Antechinus minutissimus, from Roekhampton, Australia’ 2.02. S205 o6. 5 o0.06 ors. are dies eure

Exhibition of and observations on specimens of a Species

Page

414

OPP ONEROG, saciais as ee. 2 oleate wee Gwe Fars Seca s 5 274 Extract from a letter received from Commander W. E. Cookson, R. N., concerning two large Land-Tortoises from the Galapagos Islands .... 422 Remarks on some Indian and, more especially, Bornean Mammals. (Plates XXXVI. & XXXVII.) ..... deveseetts 424 Notes on a small Collection brought by Lieut. L. Cameron, UB trom Aneola, 2 ire onc cca Sales a vere ees 678 Report on some of the Additions to the Collection of Mam- malia in the British Museum. (Plates LXIX.-LXXIV.).. 735 Description of a new Species of Lizard from Asia Minor.. 818 Gurney, J. H., Jun., F.Z.S. Letter from, containing Notes on the Breeding of a pair of the Polish Swan (Cygnus immutabilis)........ 002000000. 466 Exhibition of an example of the Lesser White-fronted Goose (Anser erythropus) killed in Egypt................ . 414 Haast, Juxuius von, Ph.D., F.R.S., C.M.Z.S., Director of the Canterbury Museum, Christchurch, New Zealand. Further Notes on Oulodon, a new Genus of Ziphioid Whales from the New-Zealand Seas.......... ; 457 Notes on the Skeleton of Ziphius nove-zealandia. (Plates MGV. & MOVIES. x. sacmubrage EaeEoe atch save stna es Goethe sO Notes on Mesoplodon floweri. (Plates XLV. & XLVI.) . 478

x

Hector, James, M.D., F.R.S., C.M.Z.S., Director of the i Geological Survey of New Zealand. Exhibition of and remarks on three feather mats, by the Maoris‘of New Zealand. 3: .0..16i. cote cos taster re 2 Hupson, Wittiam Henry, C.M.Z.S. Note on the Spoonbills of the Argentine Republic ...... 15 Notes on the Rails of the Argentine Republic.......... 102

Huxtey, Toomas H., LL.D., Sec.R.S.

Contributions to Morphology. Icurnyopstpa. No. 1. On Ceratodus forsteri, with Observations on the Classification OL PUSNOSE sa rats 6 @ 2itcc-o cua to alse em \e Retitnn es 310) vc bia ets, escarole gee On the Position of the Anterior Nasal Apertures in Lepz- WOOT ate sedi Oe bene ial ae,s S Haus LEE wee ee ae | ROU

Jacosy, MARTIN.

Description ef new Genera and Species of Phytophagous Woleopterayc 565 cos.5 ss ame ace ee Ad acn eee ee ST,

Layarp, EpGar Lreopotp, C.M.G., F.Z.S., H.B.M. Consul at New Caledonia.

Description of a New Thrush from Taviuni, one of the Fiji IE SU 0 CLS sacs Pobefessciigs ss aa seie oh Bas eae eyes ws oe wae HS Paha es eee 420

Notes on the Birds of the Navigators’ and Friendly Islands, with some Additions to the Ornithology of Fiji .......... 490

LiarpeET, E. A., C.M.Z.S.

On the Land-Shells of Taviuni, Fiji Islands, with Descrip- tions of mew, species. (Plate \.) cic ace tess 99

Newron, Aurrep, M.A., F.L.S., F.Z.8., Professor of Zoolog and Comparative Anatomy in the University of Cam- bridge. Exhibition of and remarks on a book belonging to the Rev. R. Hooper, containing a notice of the Dodo ........ 333 Note upon Canon Tristram’s recent Discovery of the Roe- buck (Cervus ecapreolus) in Palestine ..........ee....4. 700

xi Page Parker, W. K., F.R.S., F.Z.S. Memoir on AZgithognathous Birds. Part II. (Abstract). 256

Abstract of a Memoir on the Structure and Development of the Skull in Sharkssand Rays: 2. cscs. 662 oss'se acvee sa 699 Ramsay, E. Pierson, C.M.Z.S.

List of Birds met with in North-eastern Queensland, chiefly at Rockingham Baye Part Uli... piace caskaeuceers, LIA

Letter from, containing notes on the habits of some living

Ceratodi in the Australian Museum, Sydney ............ 698 Ramsay, Lieutenant R. Warp.aw, F.Z.S. On an undescribed Species of Nuthatch and another Bird from Maren-nee. (Plate: XI.) oiccug wwe cae ness 677

Row Ley, GeorGe Dawson, M.A., F.Z.S.

Exhibition of a specimen of Macherirhynchus nigripectus 414

SaLtvaport, Tuomas, M.D., C.M.Z.S.

Letter from, containing remarks on some birds mentioned by Signor D’ Albertis as seen by him during his first excursion up. the Fly River .......... wis Seahee ate Meuete ab oahais de Papeete 752

Letter from, addressed to the Secretary, concerning the discovery of a supposed new species of Drepanornis ...... 776 SALVIN, Ossert, M.A., F.R.S., F.Z.S.

Exhibition of a portion of a trunk of a pine from Guate- mala, perforated by a Woodpecker ........:..--+..- eae. Ata

Satvin, Ossert, M.A., F.R.S., F.Z.S., and Scuater, P. L., M.A., Ph.D., F.R.S.

On Peruvian Birds collected by Mr. Whitely—Part IX.

CB leben TE ye wish 2 aise so Se aes Sen oral a ate eee ere wen eo 15 Descriptions of new Birds obtained by Mr. C. Buckley in BROLVAR: get ta eet eS ae dd EE Bretiesy oe tase GeOO

Notes on some of the Blue Crows of America,......... 268

xi Page On new Species of Bolivian Birds. (PlatesXXX.-XXXIII.) 352

A Revision of the Neotropical Anatidee. (Plate XXXIV.) 358

Saunpers, Howarp, F.Z.S. On the Stercorariine, or Skua Gulls. (Plate XXIV.).. 317

On the Sterning, or Terns, with Descriptions of three new opecics. (Plate LEXT)'... ss swede >. «ses are sleremnele 638

Scuirer, Epwarp A., Assistant-Professor of Physiology, and WituraMs, D. James, Student of Medicine, in Uni- versity College, London.

On the Structure of the Mucous Membrane of the Stomach in‘the Kangaroos, (Plates*VITE=XI-) 3.2 sei eis eee 165

ScuaTerR, Puiiie Lutvey, M.A., Ph.D., F.R.S., Secretary to the Society.

Report on the additions to the Society’s Menagerie in

WecemberAS(a.. tow sca s fe 45 5 se aha eee tec ounce On some additional Species of Birds from St. Lucia, West

Tndiessor CP lates.) c..wenwe sae ee sins «ae oe 6 nee Sew eee ple Extract from a Report of the visit of H.M.S. ‘ Peterel’

to the Galapagos Islands ..caes 22sec ce ees ns Soya. wee og HLS

Exhibition of, and remarks on, an antler of a Rusa Deer.. 179

Report on the additions to the Society’s Menagerie in DANUARV AL SAO. sj casi tase csintertr tie ste ewes «ata ae TM ree 254

Exhibition of, and remarks on, a new Parrot (Conurus illigeri) belonging to the Museum of Neuchatel.......... 255

Report on the additions to the Society’s Menagerie in Bebruary 18/65 resco tac titi «sone ee Seer 273

Exhibition of and remarks on the skin of a female of Anderson's Pheasants: <i chaos eee eee 274

Exhibition of, and remarks upon, a series of skins of the Parrots of the Fiji Islands, obtained by Mr. E. L. Layard,

Xl

Page Report on the additions to the Society’s Menagerie in March 1876., (Plate XXV.) ........ 332 Report on the additions to the Society’s Menagerie in April 1876, and remarks on the Cassowaries in the Society’s Collection... CPiater SENN) 2.5 .¢.2.sieyes 4 acaeeews 2% 413 Extracts from several letters addressed to him by Dr. G. Bennett, F.Z.S., referring to the proceedings of Mr. L. M. D’ Albertis, C.M.Z.S......... 414 Exhibition of a rare Pacific Parrot, Coriphilus huhli, and remarks on its habitat ........ 421 On the Birds collected by Dr. Comrie on the South-east Coast of New Guinea during the Survey of H.M.S. ‘ Basilisk.’ (Plates XabTL.: & MEE: ) acs oo ie 459 Report on the additions to the Society’s Menagerie in May 1876, and list of Indian animals deposited by H.R.H. the Prince of Wales........ - 462 Exhibition of Land-Crabs from Ascension Island, pre- sented by Dro Sy Bs Drew: f53455 sus « salen seas 464 Exhibition of, and remarks on, the skins of a male and female Pheasant (Lobiophasis bulweri). (Plate XLIV.) .. 465 Exhibition of a drawing of a Fruit-Pigeon living in the DOCIEhY(S- CHATUCHS) 5 a cin ein 02.4524 9) aes ho Ws nes ees 519 Exhibition of a collection of birds received from Signor L. M. D’Albertis, and descriptions of two new Parrots. CREW cg i dere ces pie PAs aaa ae Ee eet: 519 Report on the additions to the Society’s Menagerie in June, July, August, and September 1876. (Plates LXVI.-LXVIII.) 693 Report on the additions to the Society’s Menagerie in Ociober-18 76. fs bots sedis os eRe ea eee Pod Exhibition of, and remarks upon, a skin of a young Rhinoceros from the Sunderbunds ................ 006. 751 Report on the additions to the Society’s Menagerie in November 18767... 2. 779

xiv Scuater, P. L., M.A., Ph.D., F.R.S., and Savin, OSBERT, M.A., F.B.S., F.Z.S.

On Peruvian Birds collected a Mr. Whitely.—Part IX. (Plate III.) ie

Descriptions of new Birds obtained by Mr. C. Buckley in

Olivine | eee ree ee ieee eh ore ide Sis SRS cn eee Notes on some of the Blue Crows of America....

On new Species of Bolivian Birds. (Plates XXX.—XXXIII.)

A Revision of the Neotropical Anatidee. (Plate XXXIV.) ;

Sexous, FrepeErtck, Jun. Exhibition of, and remarks on, a series of horns of

African Rhinoceroses .....

Saarre, Ricuarp Bowpter, F.L.S., F.Z.8., &c., Senior Assistant, Zoological Department, British Museum.

Exhibition of a specimen of Hawk-Owl (Surnia ulula), killed in Great Britain’ > ir. - 6... 52.5

Description of an apparently new Species of Owl from the Solomon Islands; s@BlatesE ITs) F.:. iiss. niece sie «sess auegee

Sowersy, G. B., Jun.

Descriptions of six new Species of Shells from the Col- lections of the Marchioness Paulucci and Dr. Prevost. (Nites TPN) anes ot tots avons Sotiale a tote eter aneh alin ea ate anal eee

Taczanowskl, L., C.M.Z.S.

Description d’un nouveau Cerf tacheté du pays d’Ussuri

méridional, Cervus dybowsktt, 2... 002. cess scsenceanses

Trimren, Rowanp, F.Z.S., Curator of the South-African

Museum, Capetown.

Letter from, addressed to the Secretary, containing re-

marks on Canis chama, Smith ........

Page

253

334

673

752

123

XV Tristram, Rev. H. B., F.Z.S.

Note on the Discovery of the Roebuck (Cervus capreolus) PASE BICRLINE! <5 <-soeeeremeea as, 9 aie fuses RG PMsorienenn ae 420

WiuiurAMs, D. James, Student of Medicine, and Scuirer, Epwarp A., Assistant-Professor of Physiology, in University College, London.

On the Structure of the Mucous Membrane of the Stomach in the Kangaroos. (Plates VIII.-XI.) ...,.,..,,..,,., 165

Plate Page I. Xephodon platyceners. cars; ng ais wete nays sisrecemasualecerouer 3 Le? Pencopeza Semperd. 4.5 vv, arcsivieus a0 a ot aii eee 13 III. “ Thamnophilus melanchrous .....002-+0000ee08%005 15 IV. Chart of Families of the order Glires.............. 61 V. New Land-Shells from Taviuni .. ..0.0:5. 000004 0 99 ae New Species of Leracolus..c: seis «> si « %o monies siete eres ase 126 VIII. Fig. 1. Stomach of Macropus giganteus............ 1X | Figs. 2 & 3. Stomach of Macropus giganteus ...... ’ | Fig. 4. Stomach of Dorcopsis luctuosa .........605 [ 16 Fig. 5. Stomach of Macropus giganteus............ pee ie Fie 6. Stomach of Dorcopsis luctuosa ............ [ XI. Figs. 7-10. Stomach of Dorcopsis luctuosa ........ J x1) ae \ Anatomy of Chauna derbiana ...cccececec eee eves 189 XV. KVL VEchinorhynchus elegans. << ios0 sam sic rsuere esi Hs eloses 200 ear PCLUVIADID UGLELi bes injec ote! -'a'e sain a edete sieiceal seiner 205 XVIII. XIX. Kerguelen-Island Arachnida .......i..ecseceeees 258 XX. New Australian and Solomon-Island Helices........ 265 AXIS (New or rare Hntozoa. c2vvij.sige «ets ces ttaess oe cnet 294 XXII. New Malayan: Lepidoptera os.sc. + steers secteaneee 308 | RTT Paleo Gaby lonicus.,.c.0. .vsea ss wie one ce tear 310 DORI V.. 5 USLENCOTOTIUS CRUENEIS. \.. sarees etnies asec e Sean ee oe OL7 RXV «2 Lol y GOGUS TROTUS NAVs a 6 wicis tue 5 emits oe ones aes ene 333 XXVI. XXVII.} Anatomy of Plotus anhinga ...0....--..05+0ee: 335 XX VAN. XIX, Dasyprocta aZzare@: ass .anciaseiec 04,0 347 XXX. Fig. 1. Calliste fulvicervix ; Fig. 2. C. argyrofenges. XXX]. Malacothraupis dentata saves css 6 s+0 00s SE 359 XXXII. Lathria uropygialis ...... AD Ocoee dons dons = XXXII... Thamnophilus subfasctatus-.... 0. o<csen+>ssmacees AEXIV. Querquedula andiwm.... cases as sco - eee eee 358

LIST OF PLATES.

xvil

Plate Page MOEN . Coles CastanOnOlus scars sG'eSia.s viz, areraveere ss ou atstem or 413 XXXVI. Tupaia tana, var. CRYSUTE.. 05.66 k ese cee cee oe | RAXVU -Viverra megaspilaad et jr sa.5 acs ca ceoav owes vc ae XXXVIII. ae Deep-sea and Littoral Corals ...........0s.eeeee 428 XLI.

ML. Manucodia comritinin aks seni s fates bares WING we XLII. Megapodius macgillivrayit .....ccceccerccenccves sce XLIV. Lobiophasis bulwerit. Fig. 1. 9. Fig. 2. d ...... 465

xv. 5 Fis: 1. Skeleton of Mesoplodon flower? .........++.

| Fig. 2. Skeleton of Ziphius nove zealandi@........ bee XLVI. } Fig. 1. Skull of Mesoplodon floweri, upper view .... ; Fig. 2. Skull of Ziphius nove zealandie, upper view XLVIL j Land-Shells from New Guinea, Madagascar, and Aus- } EVAL Ate eee see remeRe Hr ecec hore orators Cletaer a clone ore 488 XLVIII. ) XLIX. LL Anatomy of the Passeres........sceeeeeecesevens 506 LIL. LUI. } LIV. Cyclopsitia suavissima.....ccecceeccessesscesees 520 LV. Suctorial and Adhesive Foot-pads of Mammals .... 526 LVI. Figs.1,2. Deanea favoides. Figs.3,4. Farrea ees 535

LVII. Figs.1,2. Farrea perarmata. Figs.3,4. F.irregularis

LVIII. LIX.} New Egyptian Spiders..........seeecesesevceees 541 LX. Fig. 1. Anous tenuirostris ....cesceccceescecevecs LXI, |B 2, Anous melanogenysS 0. ccsevecsecsoverare | 638 Fig. 3. Anous leucocapillus......eceeeeeeeecenees

LXII. Ninow solomonis .....ccecerereceeccscorsvccens 673 TRULY. Stet agnd occsc acca ve ve bates wesc ened eeees 677 LXIV. Delphinus albirostris. Fig. 1. Specimen from eis 679

Grimsby. Fig. 2. Specimen from Lowestoft ....

LXV. Stomach of Delphinus albirostris ......+0+s00e005 686 LXVI. Corvus capellanus ....ccceccccsesaceccsccvcscere 694 LXVII. Sarcidiornis melanonota .....ceeeeeececeverevecs 695

LXVIII. Sarcidiornis carunculata .....scccevccesesasscess

TGRUNGY SCLUTUS SECCTIU: oot cots oreiche elalss oi evavere syeteyelaterel etal e's) ops >

LXX. Hystria crassispinis ...... 00 cccccccese cece eevee LXXL, Vrichaysilepur ws ois alee wainn og Sralrsle aie sina wine «ele lee = 35 EXXEL, Hapale leucopus: 64 cic.so senses orale 21 816) wouanrsings ie i

LXXITII. Loncheres caniceps ....ccccccsscsceseseccvcecce | LXXIV. Echimys ferrugineus......sccecesesececerececens J

Plate

LXXV. LXXVI. LXXVII. LXXVIII. LXXIX. LXXX. LXXXI. LXXXII.

xvill

Page New shells from the Eastern Hemisphere.......... 792 Head of Lophotragus michianus......00eccceceees Haye Butterflies from New Guinea .....:.c800ccceec0es 765 Desmacidon plumosa. 6.ccc cscs s+ so vecees wlecen os Chaling Gerticilatd. san Pak «soso teeter 768 OplitospOnGid FUCOIDES sive. aie s+. vio 0) siete seeisiodetede euels Riaphiodesme FadtOSt: « 5)s's <n ss. 20 oe ae pro : POLOGCtUS PLULINDCUS ss 5:4-¢:5iavloiw Dot sien Me eileen 776

CORRECTED DESCRIPTION OF PLATE VI. (p. 165.)

Fig. 1. Teracolus subfumosus, p. 139.) Fig. 7. Teracolus halyattes, p. 145. D: lyeus, p. 141. 8. ithonus, p. 146. 3. flaminia, p. 140. o; suffusus, p. 152. 4. —— lycoris, p. 140. 10; pseudocale, p. 154. 5. ——friga, p. 142. ll. hero, p. 150. 6. —— lucullus, p. 143. | 12. pseudacaste, p. 156,

PROCEEDINGS

OF TILE

SCIENTIFIC MEETINGS

OF THE

ZOOLOGICAL SOCIETY OF LONDON.

January 4, 1876. Prof. Newton, F.R.S., V.P., in the Chair.

The Secretary read the following report on the additions to the Society’s Menagerie during the month of December 1875 :—

The registered additions to the Society’s Menagerie during the month of December were 86 in number. Of these, 17 were acquired by presentation, 54 by purchase, | by exchange, | by birth, and 13 were received on deposit. The total number of departures during the same period, by death and removals, was 113.

The most noticeable additions during the month of December were as follows :—

A Haast’s Apteryx (Apteryx haasti) from New Zealand, pre- sented by Baron F. von Mueller, C.M.Z.S., 18th December, 1875. Two examples of this Apteryx were despatched by our esteemed correspondent from Melbourne; but only one reached us alive—the first living individual of this recently determined species (assuming that its distinctness from A. oweni is fairly established) that has arrived in this country.

A Night-Parrot (Stringops habroptilus) from New Zealand, pre- sented by Mr. T. E. Featherston, 23rd December, 1875.

Three male Moose (Alces machlis) from North Ameriea, deposited 28th December, 1875.

—_—__—.

Proc. Zoo. Soc.—1876, No. I. l

2 DR. HECTOR ON MAORI FEATHER MATS. [Jan. 4,

A letter was read, addressed to the Secretary by Mr. George Brown, Corresponding Member, dated Port Hunter, Duke-of-York Island (lat. 4° 7'S., long. 152° 22' E.), Sept. 5, 1875, stating that he had shipped by the ‘ John Wesley,’ for the Society, to the care of Dr. George Bennett at Sydney two Cassowaries, and a Cockatoo from the adjoining island of New Britain, and two Pigeons and two Parrots from Duke-of- York Island, and some other birds, whieh he trusted would arrive safely. Mr. Brown stated that he had a col- lector at work along with him, and hoped shortly to have made a good series of specimens of the hitherto almost unknown fauna of this and the neighbouring islands.

The Secretary had received intelligence from Dr. Bennett of the safe arrival of the two Cassowaries (Casuarius bennetti) and of four of the other birds at Sydney, and that they would be forwarded to the Society by the ‘ Paramatta’ on her next return voyage.

The following extract was read from a letter addressed to the Secretary by Mr. R. Trimen, Curator of the South-African Museum, Cape-town, dated 24th Nov. 1875.

“Your note (P. Z.S. 1875, pp. 81, 82) on Canis chama, Smith, leads me to think that you may be interested in hearing that there are two specimens of that species in this Museum.

“They have hitherto been labelled C. variegatoides, Smith (South Afr. Qu. Journ. il. p. 87), the example first received having been so determined by the late Curator; but on comparison of them with the characteristic plate (xviii.) in the ‘ Proceedings,’ and with Dr. Smith’s descriptions of the two species, it is clear that they are C. chama and not C. variegatoides.

“7 should be glad to hear if you know any thing about the latter species.

“The jate Dr. J. E. Gray referred it (List Mamm. Brit. Mus. 1843, p- 58) to C. mesomelas, Schreb.; but as Dr. Smith was well ac- quainted with C’. mesomelas, it seems improbable that he would have founded a new species on any thing less than a well-marked variety.

* C’. chama is more widely spread than Dr. Smith’s account would lead one to suppose, one of our two examples being from the neigh- bourhood of Beaufort (about the centre of this colony) and the other from near Caledon, a-town about 70 miles east (and a little to the south) of Cape-town.”

Dr. Hector, F.R.S., sent for exhibition three feather mats, made by the Maoris of New Zealand :—

No. 1. An ancient mat, obtained by Dr. Buller from a chief be- longing to the Upper Wanganui river. Centre of pigeon’s feathers ( Carpophaga nove-zealandice ) trimmed with feathers from the Kaka (Nestor meridionalis) and North-Island Kiwi (Apteryx mantelii), and also tufts of hair of the ancient Maori dog, now extinct.

No. 2. A mat of Kiwi feathers (Apteryx mantelli) from Tampo Lake, North Island. The harsh feel, from the prolonged shafts

a

, ai i eS ie - va ‘ . y ' , ’ 5 . t - : - 7 ' . & r a . of fi 7 . , t 7 ; = ‘ ; ; ; : ; A % : rs ; j j

=

pre) 4 — a

J.Smit,

lath

XIPHODON, PLATYCEP S372

a

Hanhart

imp

1876.] PROF. FLOWER ON THE SKULL OF A XIPHODON,. 3

characteristic of this species, is obvious. Each feather is worked into the flax of the mat.

No. 3. A mat of wing-feathers of the Kaka (Nestor meridionalis), made by the natives near Wellington.

The following papers were read :—

1. Description of the Skull of a Species of Xiphodon, Cuvier. By Wituiam Henry Frower, F.R.S., F.Z.S., F.G.S.,

&e. [Received November 16, 1875.]

(Plate I.)

The Hon. Auberon Herbert has lately presented to the Museum of the Royal College of Surgeons a fossil cranium which merits de- scription, as in some measure assisting to fill up one of the still in- numerable vacant spaces in the vast and complex history of living beings, a history gradually, slowly, but no less surely, being recon- structed by the united labours of explorers and paleeontographers in all parts of the world.

In some respects, the specimen is provokingly unsatisfactory for the purpose, partly from its own incompleteness, but especially in the absence of certain knowledge as to its locality and geological an- tiquity. As it had passed through several hands before it came into Mr. Herbert’s possession, there is no external history belonging to it, except a traditional statement that it was found in the neighbour- hood of Woodbridge, in Suffolk.

At first little more was to be seen in it than an ovoid mass, nearly nine inches long, of dark grey, very compact, micaceous sandstone, with the surface smoothly rounded, and almost polished, evidently by the action of water. Toa superficial observer it might have passed for a large rolled pebble; but closer examination showed that, be- sides having the general form of the head of an animal, the surface here and there presented darker patches, having a distinctly bony structure, which, from their situation and form, plainly revealed the general outline of the cranium within.

After a considerable amount of trouble, the closely adhering en- veloping matrix was completely cleared away. The specimen was then shown to consist of the almost entire cranium (skull without lower jaw) of an animal of the size of a small sheep, with all its cavities and external depressions filled up with a matrix of the above- described sandstone, and then so rolled as to wear down some of the most prominent parts, as the zygomatic arch and, unfortunately the whole of the crowns of the teeth; for the palatal surface was exposed, smooth and polished, and the dental characters are only indicated by the alveoli or by roots worn down to the level of the sur- rounding bone. This is a very great loss, more especially as it is mainly by the form of the enamelled crowns of the teeth, generally

1*

4 PROF, FLOWER ON THE SKULL OF A XIPHODON. |Jan. 4,

better preserved than any other part of the body, that extinct forms of the group to which this one is allied have been characterized. The anterior portion of the skull has also been broken off close to the premaxillary suture, and consequently is wanting in the specimen.

Before proceeding to the description of the skull, the question naturally arises—W hat inference can be drawn from the condition of the fossil and its matrix as to its probable origin? Several experi- enced paleontologists to whom it was shown while still partially imbedded, declared that they knew of no fossil remains in a cor- responding condition ; and on comparing it with all the Mammalian specimens from every part of the world, contained in the British Museum, not one was found agreeing with it.

It certainly approximates very nearly in most of its characters to the curious ‘‘ box stones” of the Suffolk Crag, to which Mr. Ray Lankester directed attention in the ‘Quarterly Journal of the Geolo- gical Society’ for 1870 (p. 499), though less ferruginous in colour than they generally are. If this suggestion should prove to be correct, it will confirm the indication as ‘to locality mentioned above. The “box stones”? are evidently waterworn aggregations of sand- stone, generally, though by no means invariably, surrounding some organic body, and are remnants of a broken-up formation of an earlier age than the Red Crag in which they are now found. They are boneidercd by Mr. Taneenter, from a comparison of the mol- luscous fossils found in them, to be of “ Diestien ”’ age, or approxi- mately equivalent to the so-called ‘ Black Crag” of Antwerp; but, as will be mentioned hereafter, the zoological characters of the present specimen indicate a much greater geological antiquity.

The skull is that of a rather young animal, as shown by the still open suture between the basioccipital and the basisphenoid bones ; but (at least in the case of existing Ruminants) this sign of imma- turity remains some time after all the permanent teeth are in place, as appears to have been the case in the present specimen.

The cranium differs most notably from that of all existing species of Ruminants in the breadth and flatness of the frontal region be- tween the orbits, the sudden contraction behind the orbits, vand the large extent of the temporal fossee, which is increased by well- marked sagittal and occipital crests. Hyomoschus is that to which it comes nearest ; indeed, if we could imagine a larger animal of the Traguline type (7. e. an animal with a more lengthened head, and greater surface for the implantation of teeth and for the attachment of muscles, without corresponding increase of size of the brain-cavity and orbits—the modifications, in fact, which always occur in larger, as compared with smaller, members of a natural group), we should obtain a form closely resembling the present skull. Its special pecu- liarity would still be the flatness and width of the interorbital region above, in consequence of which the cavities of the orbits look directly outwards, instead of upwards and outwards as in /Zyomoschus.

The sides of the face in front of the orbits are flat, as in the Tra- gulidee and in many trae Ruminants, without any sign of depression for a suborbital gland; but further forward, commencing just be-

1876.] PROF. FLOWER ON THE SKULL OF A XIPHODON. i)

hind the large infraorbital foramen, is a wide and deep oval depres- sion, extending over the whole cf the region above the premolar teeth. Indications only of such a depression are seen in the Tragu- lide. ‘There is no vacuity at the point of junction between the nasals, maxillee, lachrymals and frontals, as in so many Cervidee and Antelopes, and as is slightly indicated in Hyomoschus, though not in Tragulus. The sutures bounding the lachrymal bone, and be- tween the maxilla and malar, are beautifully marked by deeply in- dented and wavy lines; but the premaxillary suture cannot be dis- tinguished, being probably situated anteriorly to the point of frac- ture of the skull The supraorbital foramina are not very large, and are placed in depressions rather nearer the middle line than ite margin of the orbit, on a level with the anterior angle of that cavity ; and, as in many existing Artiodactyles, a groove is continued forwards from them.

The posterior margin of the orbits, if, as is provable, they were originally complete, have been broken away, as has the entire zygo- matic arch.

Turning to the base of the skull, the occipital condyles are lost ; but the greater part of the basioccipital, with its pair of pr minent tubercles, remains. On each side of this the oval form of the bases of the large auditory bulle can be distinctly made out, though they have been worn level to the rest of the surface of the skull. Their interior, however, can be seen to be filled with a fine network of eancellar tissue—a character common to the Suidee, Tragulidee, and Camelidze, and absent in nearly all the true Ruminants. On the ower surface of the skull, as well as above, the elongation of the middle region is a conspicuous feature.

The hinder margin of the palate is produced backwards to the extent of fully three quarters of an inch beyond the notches on each side; but as its edge has been broken off, it is impossibie to describe its true form.

Between the teeth the surface is long, narrow, and depressed along the middle line. ‘There is no sign, even at the anterior frac- tured edge, of the incisive foramina, which must consequently have been small ; but there is a conspicuous foramen opening forwards near the oliver edge of the palate opposite the second premolar tooth, and placed rather more posteriorly on the left than on the right side.

The alveoli, in most of which broken roots of teeth remain, form a continuous series along each side of the palate, as far forward as the line of fracture. Posteriorly they have been so much injured that their form and number cannot be made out with perfect cer- tainty ; but they appear to indicate teeth of the following character,

Beginning at the hinder end of the series, there are three molars, with four roots, wider transversely than from before backwards. The most anterior of the three must have been considerably smaller than the other two, which appear to have been nearly equal in size. {n front of the molars there are seven roots, rounded or transversely elongated, placed in a single line, and nearly .equidistant, indi- cating a series of compressed teeth, each with an anterior and a

6 PROF. FLOWER ON THE SKULL OF A XIPHODON. [ Jan. 4,

posterior root. Unfortunately the region in which the posterior of these teeth is situated is most damaged, and its form cannot be clearly made out; but, judging from the analogy of Cenotherium, Xiphodon, and allied forms, we have here the whole premolar series, the last having two external, and one internal root, obliterated in the speci- men, and each of the others two roots only. The canines would thus be the teeth next beyond the line of fracture ; but they evidently could not have been large, or deeply implanted, as in Tragulidze. Of the incisors, nothing can be said from actual knowledge ; but all analogies of allied forms lead to the supposition that the complete number (three on each side) were present.

It is evident that the animal to which this cranium belonged was a member of that group of Artiodactyles in which the general form of the modern Ruminants was shadowed out, but in which the typi- cal number of teeth (eleven on each side, above and below, in con- tinuous series) was still maintained, a group largely represented in the North-American Miocene strata by Oreodon and its allies, and of which the elegant little Cenotherium is one of the best-known European forms.

It differs, however, considerably in general form and proportions from any of the former as figured by Leidy, especially in the absence of a suborbital fossa, and is readily distinguished from the latter by the want of the deep median notch in the hinder edge of the palate, and by the more compressed form of the premolars, as estimated by the size of the roots. I am unable, however, to point out any character by which to separate it from Cuvier’s Xz%pho- don, constituted in the ‘Ossemens fossiles’ as a subgenus of Anop- lotherium. From the type of that form, X. gracilis of the Paris Upper Eocene, it differs, as far as can be inferred from descriptions and figures, chiefly in superior size, being about one third larger.

Another form to which it is closely allied is known as a British fossil from the Upper Eocene of Hordwell Cliff, having been de- scribed by Professor Owen under the name of Dichodon cuspi- datus*,

This animal is known by the teeth alone ; and it is singular that, as far as the comparison of the size and shape of the roots or alveolar walls will allow, there is no reason why the teeth of Dichodon cuspt- datus should not have belonged to our present specimen. Although there is not yet evidence enough to be assured of their identity, and more perfect specimens of either may show that the idea is fallacious, I yet think it necessary to point out the possibility. But then there are grave doubts, as already expressed by Gervaist, whether Dicho- don is really separable generically from Xiphodon. The main cha- racter on which the genus was founded, the peculiarity of the last lower premolar tooth, was, as the original describer himself subse- quently pointed ont, simply the result of a milk-tooth having been mistaken for a permanent onet. The British species attributed to the

* Quarterly Journal of the Geological Socicty, vol. iv. 1848, p. 86. t Zoologie et Paléontologie Frangaise, 2™* edit. (1859), p. 159. t Quarterly Journ. Geol. Soe. vol. xiii. (1857), p. 190.

1876.] DR.J. VON HAAST ON A NEW ZIPHIOID WHALE. 7

genus Dichobune are also considered by Gervais to be more properly Xiphodons ; so it is perfectly clear that a more careful comparison than has yet been made will be necessary to determine the claims of either to generic distinction.

Being always strongly opposed to the multiplication of generic designations without very adequate grounds, I shall be content in the present instance, to retain the Cuvierian name Yiphodon*, and, in the absence of any certain evidence that it belongs to any of the pre- viously described species, to distinguish it as XY. platyceps.

It may be added that all the species with which it is most nearly related, found both in England and France, belong to the Upper Eocene epoch, or ‘‘ proicene”’ of Gervais.

The principal dimensions of the cranium are as follows :—

inches. _centim. Length, in its mutilated state .......... 8°2 20°8 (About 9 inches if perfect.) From anterior margin of orbit to occipital

CTCStineeisceue sc Bat ereh aoa CaN rsrehestte oanale Dio 13°) From anterior margin of orbit to infraorbital

foramen. be 1°5 3°8 Breadth of upper aunties oe eral heereen

ORO ae ie ey sie os eee 2°8 Fa Greatest parietal breadth ....... 2°4 6°] Breadth at anterior part of temporal foscae 1:8 4.6

Height of skull (between frontal region and

hinder Pach pOupalacet eats ss wots core 2°6 6°6 HCiENG OL OLDIC. severe oaueisis 6 46 cee 13 3°3 Leneth of molar and premolar series .... 3°7 9°5 Breadth of palate between posterior molars 9 2°3 > » betweenmiddlepremolars 1:1 2°8

2. Ona New Ziphioid Whale. By Jutius von Haast, Ph.D., F.R.S., Director of the Canterbury Museum, Christ- church, New Zealand. Communicated by Prof. W. H. Frower, F.R.S.

[Received November 16, 1875.]

In the month of May of this year the Canterbury Museum re- ceived from W. Hood, Esq., of the Chatham Islands, three skulls of Ziphioid Whales taken from specimens stranded with about 25 others during the summer of last year on the Waitangi beach of the main island of that group.

They were described as ‘‘blackfish,”’ all belonging to the same school, by my informant, who moreover believes that the whole series belonged to the same species.

* Not, however, as a subgenus of Anoplotherium, from which it is perfectly distinct.

8 DR. J. VON HAAST ON A NEW ZIPHIOIP WHALE. [Jan. 4

Unfortunately the skulls were so badly separated from the body that the occipital portion has been cut off, so as to lay the brain-ca- vity open; but as they were brought over with the greater portion of the skin still attached, some hitherto unknown and, as I think, pecu- liar characteristic features in the dentition of a Ziphioid genus have fortunately been preserved.

These three skulls accord in many respects with the genus Mesop- lodon of Gervais, of which I will point out only one, viz. that they possess one tooth in each ramus of the lower jaw opposite the pos- terior edge of the symphysis, and of varying size and shape, either hidden below the gum or rising conspicuously above, according to age and sex. ‘They differ, however, from all known species of the genus by possessing in the upper jaw, starting in a vertical line above the posterior border of the mandibular tooth, a series of small conical teeth slightly ineurved, which extends to near the gape of the mouth.

I may here at once observe that these teeth are neither rudimen- tary nor are they confined to young animals, because, as [ shall show in the sequel, these three skulls are derived from individuals of dif- ferent ages, of which one is an aged (male?) animal, in which the row of teeth is best developed. It is thus evident that this series of teeth is a functional portion of the animal, and is constant and necessary for its proper nourishment, some of them being broken off, others evidently worn down from use. That these small teeth, of which the largest stands scarcely half an inch above the gums, are only rooted in the gums, does not lessen their value as a specific character of some importance.

Of the species of Zipbioid Whales inhabiting the New-Zealand seas I have obtained three, namely Berardius arnouxii (3 specimens), Ziphius nove zealandie, and Mesoplodon floweri (Haast, MS.), none of which shows the least sign or rudiments of teeth in the upper jaw. Moreover several others have been secured in New Zealand and Aus- tralia ; but nowhere can I find that, except the teeth in the lower jaw, they possessed any ; and I have looked carefully over all the different papers on the Ziphioid Whales of the northern hemisphere to which I had access, without finding the slightest mention made of the oc- currence of such a peculiar feature in their dentition.

On the contrary, Professor Flower in his excellent paper on the recent Ziphioid Whales (Trans. Zool. Soc. vol. viii. part 3), when enumerating their principal structural characters, begins by stating that they have “no functional teeth in the upper jaw.” IL believe that this term functional is rather ambiguous and can scarcely be applied to the genus under consideration, as we are totally un- acquainted with the food on which it subsists, or the manner in which the same is obtained.

It is true, these teeth do not grow from alveolar grooves in the maxillaries, but only from a groove in the gums, and have their roots implanted therein; nevertheless I have no doubt that they are always present and do perform as distinct and important functions as those of Kogia or any of the Dolphins which possess teeth of similar form.

1876.] DR.J. VON HAAST ON A NEW ZIPHIOID WHALE. 9

The first of the accompanying photographs shows the three skulls in comparison with each other; the second the middle portion of the second skull, belonging to an aged (male?) individual; whilst the following list gives the principal dimensions of these three skulls with the soft parts attached, as far as they could be ascertained; but as soon as they are macerated I shall offer some further observations on their anatcmical structure.

Table of Measurements of three Skulls of Mesoplodon Grayi, with the greater portion of soft parts adhering.

grown). (aged). (young). |

| Height of Skull from top of nasals (skin preserved) to lower border of pterygoids, the latter lying exposed...) 0 11:13 | O 11:58 | 0 912

Greatest breadth of skull across post- orbital processes of frontals............ 1 048 | 1 0-88 9-51

| Length of skull from crest of nasal bones |

to anterior border of rostrum, in a

Strarshtulinons ots.c ress s.ieaaasessenescs: 2 546 | 2 347 |1 507 | Length of ramus of lower jaw, soft parts preserved on anterior border ......... 2 Oe | es 6O'00: oS eho | From gape* of mouth to anterior bor-| der of lower jaw) 2) ass adhsesicectucs oases 1 6:50" | 4:87 10-05 From anterior border of lower jaw to| pa CentreOk tOOtM terse .cssstendentecese see 10°75 10:12 5-00 From centre of tooth to gape of mouth. 7°75 675 5-05 Breadth of lower jaw at centre of We MRLOOLM ES tiarsa cute wssen cst ce sedsorecessaves 2°31 2°69 1-75 | Distance from extremity of rostrum to ficsteaMteriOr tOOUM em resmcdoesseeas -e8: 11:06 10°75 5°62 Distance from gape to end of teeth ... 1:02 1:37 1:40 Hye, perpendicular diameter, about ... 2:25 2°27 | Opening of blower, the two extremities slightly directed backwards, about... 4:50 4:50 3°25 Number of teeth in upper jaw ......... 19 Al 17

I should have liked to give also in this list the breadth of the ros- trum at the anteorbital notches, as it would have supplied another im- portant point for comparison ; but the coverings prevented this ; also I was not able to give the total length of each skull, owing to the oc- cipital portion being cut off ; but the length of the skulls from crest of nasals to anterior border of the rostrum, as well as the length of the ramus of each mandible, will supply this deficiency and offer us sufficient material for comparison.

* The drying of the skin has been so unequal in the different specimens, and

even on the two sides of the same skull, that the position of the gape cannot be fixed with?precision.

10 DR. J. VON HAAST ON A NEW ZIPHIOID WHALE. [Jan. 4,

Examining the skulls separately, we find that the one marked No. 1 is longer but narrower than No. 2, This is still more striking when we compare the two rostrums with each other, that of skull No. 1 being considerably narrower than that of skull No.2. The same observation applies to the mandibles, which in No. 1 only widen very gradually and are much narrower all along than those of skull No. 2. In fact, if both skulls had been obtained separately I believe that they would probably have been assigned to two distinct species.

a. Side view of upper and lower jaws, covered with the dried skin, of No. 2 (aged male ?), showing the row of small teeth above and the single large mandi- bular tooth. From a photograph.

6, Four of the upper teeth, with the whole of their roots exposed ; natural size.

When the skull No. 1 was first examined by me, the sharp point of a tooth in each ramus of the lower jaw, when passing the finger over the gums, was discernible; but I doubt if this was to be felt before the gums were dried up.

In cutting a portion of the gums away, the apex of a very flat tooth, rather acutely triangular as far as visible, was exposed, which stands about one eighth of an inch above the upper surface of the ramus. This tooth is imbedded in a very narrow alveolar cavity situated near the posterior edge of the symphysis, the ramus here scarcely bulging out ; this is still more obvious if we compare that portion of the ramus with that of skulls Nos. 2 & 3.

Above the posterior edge of the small tooth in the lower jaw, and which without doubt has to perform some function, notwithstanding that it is covered by the gum, a row of small conical teeth, the apices slightly incurved, begins on each side of the upper jaw, reaching within an inch of the gape of the mouth, which, however, may have somewhat retreated by the drying of the skin.

These small teeth are situated in a well-defined dental groove in the gums. There were 19 teeth on each side, of which, however, several are broken off. They are from 0°20 to 0°40 inch long, and occupied a line 6°12 inches in length, standing nearly the eighth of an inch apart. Of the whole series, the first or anterior tooth is the smallest, the succeeding ones gradually getting larger till the eighth, and then maintaining the same size to nearly their termination.

1876.] DR.J. VON HAAST ON A NEW ZIPHIOID WHALE. Hi

The crowns of the teeth stand at about the same level with the cen- tral line of the palate. The opening along the upper surface of the rostrum is still unclosed, thus showing that the animal is not so aged as the next specimen, No. 2.

I may here add that the rostrum in all three skulls is half an inch shorter than the mandible, and that it lies in a well-defined groove in the latter.

Skull No. 2.—The measurements of this skull, as far as I was able to obtain them, show that, as previously stated, it was not so elongate as the former, but somewhat broader and more massive in all its pro- portions. The ramiof the mandible widen much sooner than those of the former; about 7 inches from their anterior extremity they ex- pand considerably in order to form the alveolar cavity for a large tooth which here rises conspicuously on both sides, having a vertical position. This tooth has a compressed triangular shape, i is “Qi inches broad at its base on the line of the gums, and rises 13 inch above them.

On the inner side near the top it is slightly abraded, and on the outside broken considerably, so as to suggest that the animal used it for the purpose of defence or attack. This injury has taken place on both teeth, so that they have lost their point and show a ragged horizontal apex with a width of nearly a quarter of an inch.

From behind the tooth the rami expand very little as far as the gape.

A similar row of small teeth, described as occurring in the first specimen, exists also in this second skull; but there are apparently only 17 of them. ‘Their position is exactly the same as in the foregoing, the first standing exactly above the posterior edge of the base of the large tooth in the lower jaw.

The teeth have the same form as those previously described, except that they are generally thicker; this becomes conspicuous with the 7th tooth, after which they gradually increase to the 13th, which is 2 of an inch thick at its base and stands 0°45 inch above the gums. They then keep nearly the same size to the posterior end of the series.

As the space on which these 17 teeth stand is only 4°25 inches long, besides their greater stoutness they are far more crowded than in the first-described skull.

Owing to the fact that the gums have dried more thoroughly in this than in the two other skulls, iv both of which the teeth stand erect with the curve of the apex directed inwards, the teeth in this skull are no longer in their normal position, but le somewhat forwards on the palate.

The groove in the upper surface of the rostrum, between the pre- maxillaries, is filled by a convex ridge of dense bone with a small channel on each side. That this is only caused by age, and that it is neither a sexual nor a specific character, is proved by the fact that the next skull, No. 3, which is doubtless a young half-grown specimen of the same sex as the one under review, has this groove on the top of the rostrum still open, and thus resembles the skull No. 1 although in the latter that groove is narrower and more shallow.

Skull No. 3.—Assuming that the last-deseribed skull belongs to

12 DR. J. VON HAAST ON A NEW ZIPHIOID WHALE. [Jan. 4,

an aged male, the measurements of the third skull under consideration must lead us to the conclusion that it is that of a young half-grown male. Beginning with the lower jaw, the same form as in the fore- going is observable, the rami expanding considerably as soon as we reach the neighbourhood of the alveolar eae and although the tooth in the same is only small, and stands only 0°25 inch above the edge of the ramus, that alveolar cavity is much more bulged out and has a different form from the first (or female ?) skull described.

The apex of the tooth was distinctly visible, and seemed to have

already pierced the gums when the animal was alive.

The row of teeth in the upper jaw, however, which have the same form as in the skull No. 2, are smaller and somewhat more slender. They begin likewise above the posterior end of the alveolar cavity.

There are, as inthe preceding skull, 17 teeth on each side, occupy- ing a length of 2°48 inches. They stand more closely together than in the supposed female skull No. 1, thus also agreeing with the second skuil in that respect.

In volume vi. of the Transactions of the New-Zealand Institute, Dr. Hector describes the lower jaw of a Ziphioid Whale under the title ‘‘ Notice of a variation in the dentition of Mlesoplodon hector, Gray.”

It is difficult for me to conceive by what process the tooth in the lower jaw which, in Mesoplodon hectori, stands at the anterior end of the ramus, could have travelled as far backwards as to stand now opposite the posterior edge of the symphysis. Hitherto I have be- lieved that the position of the mandibular teeth was constant and a valuable specific character—an opinion which, as faras I am aware, is held by the most eminent cetologists, and which the observations I was able to make on the three skulls under review amply confirms. Moreover I[ wish to add that a comparison of these three skulls with the skull of Mesoplodon hectori, Gray, in the Canterbury Museum, and which is derived from an aged specimen, shows at a glance the distinct specific characters.

Weare only at the beginning of the study of our Ziphioid Whales ; and I have no doubt that year by year new material will come to hand ; so that by the lumping of two distinct species into one, as at- tempted by Dr. Hector, and for which no tangible reason can be as- signed, only confusion will be created.

The occurrence of hidden teeth in the gums of Ziphius australis, Burmeister, of which he gives a careful description in his ex- haustive paper, ‘‘ Descripcion detallada del Epiodon australe” in the ‘ Anales del Museo publico de Buenos Ayres,’ part v. page 328, is a point of great interest. On first thought, one might assume that that specimen was so young that the teeth had not yet pierced the gums, and that animals belonging to that species when full-grown would be possessed of a row of teeth in each jaw resembling those of Mesoplodon grayt. However, two (and what I think fatal) objections have to be urged against such a theory.

The skull of No. 3 belongs doubtless to a younger specimen than

ee epaey, lee] aay Niels i aay (im) ard ae) bs A. Lo Loy be 4 4 ok i \ bh ob Wy 4 Vy Et ETUBL' 79 JN Win 19a” “ture

1876.] MR. P. L. SCLATER ON BIRDS FROM ST. LUCIA. 13

Ziphius australis; nevertheless the row of teeth standing above the gums was perfectly formed; and, secondly, the specimen of Ziphius nove zealandie, of which the Canterbury Museum pos- sessses a complete skeleton, was an aged female and obtained in the flesh, but did not show the least trace of any row of small teeth above the gums.

I have examined carefully the gums of the new species in both jaws, where no teeth were visible, but without the least success, no hidden teeth being in existence anywhere.

Finally I propose to designate this new Cetacean by the specific name of grayi in memory of the late Dr. J. E. Gray, to whom New Zealand is so much indebted for his contributions towards the better knowledge of its natural history.

Conclusion.

In summing up the evidence which the three skulls under review present tous, the following points may be accepted as fully esta- blished :—

Ist. That there exists a Ziphioid Whale in the New-Zealand seas which possesses a mandibular tooth at the posterior edge of the symphysis, either hidden below the gum or standing conspicuously above it, according to age or sex.

2nd. That the skull of one of the sexes (probably the female) is longer but narrower and lower than that of the opposite (probably the male) sex—the latter possessing also a large triangular compressed tooth rising above the gum, which in the other (probably female) sex Is much smaller and almost hidden below the gum.

3rd. That both sexes possess permanently in the upper jaw a row of small conical teeth with the apex slightly incurved, which, although only rooted in the guns, have to perform important functions in the nourishing-process of the animal.

3. On some additional Species of Birds from St. Lucia, West Indies. By P. lL. Scuater, M.A.; Ph.D., F.R.S., Secretary to the Society.

{Received November 30, 1875. | (Plate II.)

The Rev. J. E. Semper, of St. Lucia, who has already done so much to make us acquainted with the ornithology of that island, has lately forwarded to me a third collection of birds, which I hee now the pleasure of exhibiting. It contains examples of eight species not included in my two former articles on this subject*, and among them two specimens of a very remarkable form, which

* P. Z.8. 1871, p. 263, and 1872, p. 647.

14 MR. P. L. SCLATER ON BIRDS FROM ST. LUCIA. [Jan. 4,

appears to be referable to a new genus of Mniotiltidee. The fol- lowing is a list of the species, with the local names as given by Mr. Semper :—

1. Thryothorus mesoleucus, sp.nov. Local name “ Rossignol.”

2. Leucopeza semperi, sp. et gen. nov. Local name, “ Pied- blanc.”

3. Setophaga ruticilla (Linn.). Local name, “ Carrougette.”’

4. Progne dominicensis (Gm.). Local name, ** White-breasted

Swallow.”

: : : ‘

5. Euphonia flavifrons (Sparrm.). Local name, ‘ Moisson a couleurs.”

6. Phonipara bicolor (Linn.). Local name, ‘ Grass-sparrow.”’

7. Aigialitis semipalmata (Bp.) Local name, “ Bécasse a collier.”’

8. Tringa fuscicollis (Vieill.). Local name, ‘ Bécasse.”’

I append descriptions of the two new species.

TuHRYOTHORUS MESOLEUCUS, Sp. Nov,

Supra terreno-brunneus, alis caudaque nigro transfasciatis, uropy- git plumis laxis, albo sub apicem punctatis: subtus pure albus hypochondriis et crisso fulvis, hoc indistincte nigro maculato : rostro superiore corneo, inferiore albicante, pedibus fuscis : long. tota 4:0, ale 2°0, caude 1:5, rostri a rictu ‘8.

Hab. ins. St. Lucia Antillarum (Semper).

Mus. P. 1. 8.

Obs. Minor statura quam TJ’. martinicensis, et rostro longiore

tenuiore et magis incurvo: quoad colores abdomine albo satis diversus.

LEUCOPEZA SEMPER], gen. et sp. nov. (Plate II.)

Leucopeza*, gen. nov. ex familia Mniotiltidarum, ad Helmintherum, Helminthophagam et hujusmodi genera spectans, rostro fere simili, sed alis rotundatis, remige tertio et quarto longissimis, secundo quintum equante, primo quam sextus paxlo breviore distinguendum. Ptilosis fere unicolor, cineracea, immaculata. Pedes fortes. Tarsi elongati. Cauda paulum rotundata.

LEUCOPEZA SEMPERI, sp. nov. (Plate II.)

Cineraceus unicolor, dorso postico in olivaceum trahente, subtus pallidior, medialiter albescens, ventre medio fere pure aibo: rostro corneo, pedibus albis: long. tota 5°7, ale 2°7, caude 2°2, tarsi 0°9, rostri a rictu 0°8.

Hab. ins. St. Lucia Antillarum (Semper).

Mus. P.L. S.

* Acukds, albus, et wéZa, pes—ex nomine vulgari “ Ped-blane.”

SEA EYe

+

ANNDAT

mit

1876.] MESSRS. SCLATER AND SALVIN ON PERUVIAN BIRDS. 15

4, Note on the Spoonbill of the Argentine Republic. By W. H. Hupson, C.M.Z.S.

[Received November 17, 1875. ]

It has been said that Spoonbills ‘ obtain their food by shovelling in the mud with their beaks.’’? This is perhaps true of the Kuro- pean bird; the Spoonbills which I have observed feeding certainly obtained their food exclusively from the water, as Flamingoes do.

In reference to the Rose-coloured Spoonbills of America, I believe ornithologists have been mistaken in referring them all to one species.

Whether two or only one species existed was a moot question a century ago: it has been decided that there is but one, the Platalea ajaja, and that the paler-plumaged birds, with feathered heads and black eyes, and without the bright wing-spots, the tuft on the breast, horny excrescences on the beak, and other marks, are only immature birds. Now it is quite possible the young of P. aaja resembles the common Rose-coloured Spoonbill of Buenos Ayres ; but in that country, for one bird with all the characteristic marks of an adult P. ajaja, we meet with not less, Lam sure, than two or three hundred examples of the paler bird without any trace of such marks.

This fact of itself might incline one to believe that there two dis- tinct species, and that the common Platalea of Buenos Ayres inhabits the temperate regions south of the range of the true P. ajaja.

Other facts confirm me in that opinion. A common Spoonbill was kept tame by a friend of mine seven years, at the end of which time it died without having acquired any of the distinguishing marks of P. ajaja.

I have dissected three examples of the latter species, and observed in them the curiously formed trachea recently described by Mr. Garrod*. I have shot perhaps a hundred specimens of the common bird ; for they are extremely abundant with us. Of these I have opened about thirty, but in none of them did I find this form of trachea. I am therefore convinced that we have two distinct species of rose-coloured Spoonbill, inhabiting different portions of the continent.

5. On Peruvian Birds collected by Mr. Whitely. By P. L. ScuateR, M.A., Ph.D., F.R.S., and Ossert Satvin, M.A., F.R.S.—Part IX.+

[Received December 8, 1875. ] (Plate III.)

The ninth collection of Mr. Whitely’s Peruvian birds, now before us, has been formed in the same district of High Peru as the last was. It contains examples of sixty-five species.

* P. ZS. 1875, p. 297. t For Part VIII. see P. Z.S. 1874, p. 677.

16 MESSRS. SCLATER AND SALVIN ON PERUVIAN BIRDS. [Jan. 4,

Maramora, Potrero, and Huiro are villages in the valley of Santa Anna, north of Cuzco, at elevations of 4000, 4500, and 4800 feet

respectively.

vious papers on this subject. The following is a complete list of the species :—

The other localities have been mentioned in our pre-

*

CO CONT S CUB OD BO

5

— —

12

38

*46

. Conirostrum, sp. inc.

2. Cyanocorax incas (Bodd.)

. Parula pitiaywmi (Vieill.) . Geothlypis velata (Vieill.)

. Setophaga verticalis, Lafr. et d’Orb. ...... . Vireosylvia olivacea (Linn.)..........:000000

eee ereecceeses

Atticora cyanoleuca (Vieill.) Piaphoniivap (ho) kt eo . Tanagra corlestis, Spix.....c00.0...ssseeeses oes Se EE DOP ISTEl tt Senaanoocnconero scoDbonsancase darwini, Bp.

. Ramphocelus atrosericeus, Lafr. et d’Orb.

Tachyphonus melaleucus (Sparrm.)......++

. Saldator magnus (Gm.).....00sc00.s.ceeceseee . \Onchesticus ater (GiIM.) scas-sieseccese <i.)

. Spermophila gutturals (Licht.) ...........- . Coryphospingus cristatus (GM.) ........60..

. Phrygilus atriceps (Lafr. et d’Orb.).........

fruticeti (Kittl.) . Poospiza cesar, Scl. and Salv............0++- . Ostinops atrovirens (Lafr. et d’ Orb.) . Dolichonyx orizivora (Linn.)

. Muscisaxicola rubricapilla(Ph. et Landb.) fluviatilis, Sel. et Salv. . Todirostrum cinercum (Limn.)............06 . Euscarthmus wuchereri, Sel. et Salvy. ...... . Elainea pagana (Licht.) s ——— JUAS, SCL... ioe ts cee esse eccetenscosscences albiceps (Lafr. et d’Orb.)

teem eer ecoee

Nh ————, MIACENS, ANClasehons aces voetmcoua secs icine obscura (Lafr. et d’Orb.).........06005 . Sublegatus griseocularis . Myiozetetes cayennensis (Linn.) . Myiodynastes chrysocephalus (Tsch.) ...... . Myiobius nevius (Bodd.)........-cceeceeecees . Myiarchus erythrocercus, Sel. .........0000+ . Tyrannus melancholicus, Vieill. ............ . Placellodomus striaticeps (afr. et d’Orb.) . Thamnophilus melanchrous, sp. Nov. ....-. . —-- radiatus, Vieill. . Formicivora rufatra (Lafr. et d’Orb.)

2. Phaethornis guyt (Less.) ......cssececsseeeees

. Panoplites matthewsi (Boure.).....-...000+6 . Acestrura mulsanti (Bourc.) .....cceceeeeee . Steganura add@ (Boure.).......cccccecereees . Eupetomena hirundo, Gould. ...............

Localities.

Huiro. Huiro, Maranura. Huiro, Potrero. Maranura, Huiro. Maranura. Maranura. Maranura. Huiro, Potrero. Maranura. Paucartambo. Maranura, Potrero. Maranura, Huiro, Potrero. Huiro. Potrero, Huiro. Maranura. Potrero. Paucartambo. Paucartambo. Paucartambo. Huiro. Paucartambo. Huiro. Tinta. Potrero. Maranura, Potrero. Maranura. Maranura,

Huiro, Maranura, Potrero.

Maranura,

Huiro.

Maranura.

Huiro.

Potrero.

Mayranura.

Huiro.

Paucartambo.

Huiro, 4800 feet.

Huiro, Maranura.

Maranura.

Huiro.

1876.] MESSRS. SCLATER AND SALVIN ON PERUVIAN BIRDS. 17

6. ConrROSTRUM, sp. ine.

A single skin of what is probably the female of a new Conirostrum, allied to C. albifrons or possibly of a new Dacnis.

7. EUPHONIA, sp. inc.

Two skins of the female of a thick-billed Huphonia of the group allied to #. violacea, probably of EF. laniirostris (Lafr. et d’Orb.).

30. ELAINEA PLACENS, Sclater.

This brings the range of this species down to Peru. We have compared skins from Mexico, Guatemala, Veragua, Panama, Bogota, and Ecuador. The last-named (2. implacens, Sclater, olim) agree with the Peruvian in being rather darker on the back ; but a Bogota skin is barely different in this respect from Sclater’s Mexican type.

32. SUBLEGATUS GRISEOCULARIS.

This Tyrant bird, of which Mr. Whitely sends a pair from Mara- nura, is very closely allied to the Venezuelan S. glaber, but is recog- nizable by its shorter smaller bill, shorter crest, and the paler colour of the back. Sclater’s collection contains a single immature example of the same form from Mendoza (Weisshaupt), labelled ‘ Hlainea griseocularis, Landbeck ;’’ and there is a second skin from the same source in Salvin and Godman’s collection. Whether this name has ever been published or not we are not sure; but we adopt it as a designation of this allied species, which is generally of the same form as its northern congener.

Proc. Zoo. Soc.—1876, No. IT. 2

18 MESSRS. SCLATER AND SALYVIN ON PERUVIAN BIRDS. |Jan. 4,

39. THAMNOPHILUS MELANCHROUS, sp. nov. (Plate III.)

Ater ; interscapulit macula magna, campterio et tectricum margi- nibus albis: ventre lineis quibusdam et marginibus angustis albis variegato: cauda nigra, rectricum trium lateralium apict- bus et macula in rectricis utrinque extime pogonio externo medio albis: rostro et pedibus nigris: long. tota 6:0, ale 2°8, caude rectr. med. 2°4, ext. 2°1.

Hab. Peruvia alta prope Huiro (Wiitely).

Ob. Species quoad formam et colores Thamnophilo aspersiventri

maxime affinis, sed ventre nigro diversa.

46. EvurpETOMENA HIRUNDO, Gould, Ann. N. H. ser. 4, vol. xvi. p. 370 (1875).

Mr. Whitely sends the following notes on this interesting new discovery :—

“TI found these birds at Huiro in the valley of Santa Ana, at an elevation of 4800 feet; they rarely approach a flower, but appear to take their food hawking about in the air, in the manner of Swal- lows—in fact, at first sight might be easily mistaken for such birds. Length 62 inches, bill | inch, wing 3 inches; eyes and bill black ; legs, toes, and claws black.”

52. BoLBoruy:cHus ANDICOLA (Finsch).

Psittacula andicola, Finsch, P. Z.S8. 1874, p. 90; Sel. et Salv. P2Z.'S. 1874,p. 679:

A third example of this little Parrot from Paucartambo. On the whole we think this species better referred to the genus Boldo- rhynchus, being unquestionably allied to B. orbignesius.

58. CoLUMBA ALBIPENNIS, Sp. nov.

Columba maculosa, Scl. et Salv. P. Z. S. 1869, p. 600.

Supra fuscescens, capite et collo postico vinaceo lavatis: dorse postico et tectricibus supracaudalibus columbino-griseis: tectri- cibus alarum minoribus albido terminatis, tectricibus majoribus albo late terminatis, fasciam alarem distincta formantibus: alis Susco-nigris: cauda Susco-grisea, fascia lata terminali nigra : subtus griseo-cerulea, collo antico (nisi in gula) et pectore vina- ceo indutis : alis subtus pallide columbino-griseis: rostro nigro, basi flavido, pedibus rubris: long. tot. 14°5, ale 9-0, caude 5:0, rostri a rictu 1*1, tarsi 1°2.

Hab. Peruvia alta, Pitumarca (Whitely) ; Bolivia (D. Forbes).

Obs. Sp. C. maculose affinis, sed fascia alari alba, corpore subtus grisescentiore et pagina alarum inferiore pallidiore grisea distin- guenda.

‘i his species, though closely allied to Columba maculosa, appears to take its place in Bolivia and Peru, from both of which countries we possess specimens. The true C. maculosa is found further south ; we have specimens of it from Mendoza (Weisshaupt), and from the Rio Negro, where Mr. Hudson obtained it. (Cf. P. Z.S. 1872, p. 545. |

1876. | DR. O. FINSCH ON SOME FIJIAN BIRDS. 19

63. GALLINAGO ANDINA, Tacz.

Gallinago frenata, Scl. and Salv. P. Z. S. 1869, p. 156.

G. andina, 'Tacz. P. Z. 8. 1874, p. 561.

Having compared one of Mr. Whitely’s skins with M. Taczanow- ski’s typical specimens, we find them to be identical, and, more- over, that the bird we attributed in a former paper to the common G. frenata of Eastern South America really belongs to a distinct species, as shown by M. Taczanowski. Without placing much stress upon differences of coloration (a variable and unsatisfactory character in the Snipes), the shortness of the tarsi in G. andina at once shows its distinctness from G. frenata. The other dimensions are nearly the same in the two species: the bills appear to be shorter in G. andina ; but upon this character no value can be placed. Mr. Whitely (P. Z. 8S. 1869, p. 156) says that “the legs and toes are brownish flesh-colour,” i.e. in life. In the skin they are much paler than those of G. jrenata ; so that possibly a distinction here exists between the two birds.

6. Notes on some Fijian Birds, including Description of a new Genus and Species. By Orro Finscu, Ph.D., C.M.Z.8., &e.

[Received December 8, 1875.]

The Museum Godeffroy at Hamburg has received a small collec- tion of birds from Mr. Theodor Kleinschmidt, of Ovalau, upon which I beg leave to make a few remarks. I have also the pleasure of describing a curious new Malurine form, which offers a very interesting addition to the avifauna of the Fiyjis and Central Polynesia.

TIALCYON SACRA, Gin.

One specimen with the blue of the head surrounded by a band of bright buff; the nuchal collar, sides of vent and flanks, the under wing- and tail-coverts also strongly tinged with buff. Apparently a young bird, agreeing with our descriptions (Finsch & Hartl. ‘Orn. Centr.-Polyn.’ p. 34, ‘jiingerer Vogel von Viti’’) and that of the “young” by Sharpe (Kingf. pl. 85).

CoLLocALia spopiopyGiA, Peale. Two specimens, agreeing in every respect with specimens from the Navigators’ (Upolu).

MyZoOMELA JUGULARIS, Peale. An old male in full plumage ; rump and upper tail-coverts scarlet; throat and crop pale orange, remainder of underparts yellowish.

DryMOCHERA, gen. nov.

(dpupos, sylva; yaipw, gaudeo.) The systematic position of this new and curious Malurine form

is between Camaroptera and Orthotomus. The former Sas a much 2

20 MR. A. H. GARROD ON THE [Jan. 4,

shorter, rounded tail; Orthotomus, on the contrary, has a cuneate tail, whereas in this genus the tail is only graduated. The wings are a little longer and Jess rounded than in Orthotomus, the fifth and sixth quills being the longest, the fourth and seventh scarcely shorter, the first considerably shortened, half of the fifth ; the bill is straight, at- tenuated and subulate, a little more robust than in Orthotomus, as are likewise the legs and feet.

DryMOCHZERA BADICEPS, Sp. NOV.

Upper parts olive-brown, tinged with reddish brown on the rump and upper tail-coverts; head above to the nape chestnut-reddish ; a narrow greyish superciliary stripe, extending to the temporal region, and bordered below by a narrow dark line, which runs from the lores through the eyes; quills and tail dark olive-brown ; under parts, from chin to the middle of vent white; sides of head, neck, and breast washed with brownish-grey, remainder of underparts pale earthy brown; bill dark brown; feet pale brown.

al. caud. rect.ext. culm. rict. tars. dig. med. 93M 990M" 1 7 5a gi! gill 6!"

Mr. Kleinschmidt discovered this remarkable httle bird during an expedition into the interior of Viti-Levu, but could obtain only a single specimen.

MyYIoLesTEs NiGRoGULARIS, Layard.

Lalage ! nigrogularis, Layard, P. Z.S. 1875, p. 149.

Mr. Layard has described this interesting bird wrongly as a Lalage : it is a typical A/yiolestes, agreeing in its generic characters with our M. heinei (H. & F., P.Z.S. 1869, p. 546) from Tongatabu. Mr. Layard, strangely enough, does not mention this characteristic bird in his last paper on Fijian birds (P. Z. 8. 1875, p. 423).

Mr. Kleinschmidt obtained but one specimen of this species at Ovalau.

RHIPIDURA ALBOGULARIS, Layard (nec Less.).

One specimen, agreeing very well with Mr. Layard’s description (P. Z. 8S. 1875, pp. 29, 434). This is a very excellent and peculiar species, not to be confounded with any of its allies.

MYIAGRA CASTANEIVENTRIS, Verr.

One old male as figured (F. & H. Orn. Centr.-Pol. t. ix. f. 2), and corresponding in every respect with specimens from the Navigators’ Islands.

7. On the Cecum Colt of the Capybara (Hydrocherus capy- bara). By A. H. Garrop, M.A., F.Z.S., Prosector to

the Society. [Received December 9, 1875. ] In no work on anatomy with which I am acquainted can I find any reference to the peculiarities of the caecum coli of the Capybara,

1876. } CCUM COLI OF THE CAPYBARA. 21

which are but an extreme exaggeration of those observed in many of the allied forms.

In most of those mammals in which a cecum is present, that organ is simply a direct continuation backwards of the colon beyond the place of junction of the small and large intestines. In some Rodents, however, this is not the case, the sacculated ceecum in them not being a direct continuation of the larger gut, but a lateral diverticulum from a true but simple cecum.

In his account of the anatomy of Capromys fournieri*, Prof. Owen remarks that the arrangement at the ilio-colic junction is such that ‘the two orifices of the blind intestine [that into the ileum and that into the colon] are analogous to the cardia and pylorus of the stomach ;”’ and in his ‘Anatomy of Vertebrates’+ the same illustrious

Sacculated and simple ceca of the Capybara. The continuation of the colon isseen at a. The small intestine at its termination cannot be seen, being hidden in the proximal angular bend of the sacculated czecum.

author tells us, with reference to the same animal, that “ the caecum is marked off from the colon by a valvular structure, similar to that at the end of the ileum.” This is an approximation to the condition which obtains in the animal under consideration.

In the Capybara the small intestine enters the enormous saccu-

* P. ZS. 1832, p. 70. + Vol. iii. p. 425.

22 MR. A. H. GARROD ON THE [Jan. 4,

lated ceecum at about an inch from its open extremity, and its rela- tions to it are not in any way peculiar. The sacculated czecum is nearly two feet long, and is traversed by four longitudinal bands. At its open end, which is an inch beyond (that is, further from the cecal extremity than) the ileo-czecal valve, it is constricted by a circular sphincter muscle, which forms the orifice of communication with the rest of the cylindrical large intestine. The colic surface of this sphincter is situated in the side of the colon, three inches from the blind extremity of a true, simple, thick-walled, slightly pyriform

Diagram of the conyolutions of the colon in the Capybara. The dotted line represents the caecum springing from the side of the dilated end of the large intestine, and running forward to the diaphragm. a, ileo-cxcal valve ; 4, rectum.

cecum, which is directly continuous with the colon, and is indistin- guishable from it in structure. This second czecum is, as indicated above, three inches from the extreme end to the centre of the orifice by which it communicates with the sacculated one. Superficially its

1876. ] CCUM COLI OF THE CAPYBARA. 23

longitudinal muscular coat is strongly marked, covering it perfectly uniformly.

The ileo-ceecal valve is linear and longitudinal ; it projects a short distance into the sacculated ceecum from above as a tube with slightly turned lips, of which the inferior is a little the longer and larger. There are some thickened gland-patches in the sacculated caecum, and a large one in the colon, at the margin of the sphincter which is towards the continuation of the large intestine; three or four others are situated irregularly in the walls of the true caecum.

The disposition of the colon is peculiar and interesting. The accompanying sketch (fig. 2, p. 22) will explainit best. It was taken from the view obtained of them as the animal lay on its back. As is well known, the large intestine commences in the left hypochondriac region, the true caecum capping the end of the sacculated one an- teriorly. The gut then, with a curve to the right, runs back to the hypogastric region, where, with a reversed figure-of-eight twist, it gets into the normal position of the ascending colon. It so reaches the right hypochondriac region, and then commences to form, in the transverse colon, coils very similar to, though on a smaller scale than those in Jndris among the Lemurs and in the Artiodactylate Ungulata, the much-developed loop being twisted on itself to the left side. After reaching the left hypochondrium the descending colon continues straight to the sigmoid flexure, which is strongly developed, and thence to the rectum.

The sacculated ceecum being bound to the first part of the colon by bands of equal length (about 23 inches), follows the course of that canal, and is therefore doubled on itself, not, as Prof. Owen remarks, occupying the posterior half of the abdomen, but running forwards towards the diaphragm, above the colon, till its caput arrives in the right hypochondriac and epigastric regions, where the ruminant-like coil above referred to is strongly bound to it en its under or ventral surface.

Neither in Cavia, Dolichotis, Capromys, nor in any of the allied forms with which I am acquainted, does the strong sigmoid curve of the large intestine, at the commencement of the sacculated cecum, develop into a true secondary ceecum in the manner that it does in the Capybara.

Whilst on the subject of the viscera of the Capybara, the following measurements of those of an adult male will not be out of place— small intestine 21 feet, large intestine 6 feet 7 inches, caecum | foot 10 inches.

The liver is comparatively simple. The gall-bladder is pyriform, situated in a cystic fossa, not reaching the free margin of the gland. The right central lobe is slightly more bulky than the left lateral, which is more than twice the size of the left central, which, again, is somewhat larger than the caudate. ‘The spigelian lobe is minute, and bifid as in so many Rodents.

24 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

8. Contributions to Morphology. Icurnyoprstpa.—No. 1. On Ceratodus forsteri, with Observations on the Classifi- cation of Fishes. By Prof. T. H. Huxury, Sec. B.S.

[Received January 4, 1876.]

Two specimens of Ceratodus forstert have come into my posses- sion within the last two years. The first was kindly placed at my disposal by the Secretary of this Society some time ago; but I was unwilling to dissect it until I had a second. This desideratum was supplied by my friend Sir George MacLezy, who, on a recent visit to Australia, was kind enough to undertake to obtain a Ceratodus for me, and fulfilled his promise by sending me a very fine and well-preserved fish, rather larger than the first. The first was 32 inches long, the second only 30 inches, though a considerably stouter fish.

I need hardly say that I have little to add or qualify in the general description of the exterior structure given by so accomplished and experienced an ichthyologist as Dr. Giinther*. Only in one, point do I find my interpretation of the facts widely discrepant from his ; aud that is in regard to the position of the external nostrils.

Dr. Ginther says, ‘‘As in Lepidosiren, there are two nasal apertures on each side, both being situated within the cavity of the mouth.”

That anterior nasal apertures should be situated, in any sense, ‘within the cavity of the mouth” would be so singular a deviation from the otherwise universal rule, that the anterior nares of verte- brated animals are situated outside the mouth, on the surface of the head, that conclusive evidence must be producible before the ano- maly can be admitted to exist; and, so far as my observations go, that conclusive evidence is not only wanting, but the contrary is demonstrable.

In Ceratodus, it is easily seen that the anterior nares are not oc- cluded when the mouth is shut by the apposition of the edges of the mandible to the palate. The anterior nares, in fact, lie altogether outside and in front of the contour of the mandibles, on the under concave surface of the anterior part of the head. The median portion of the margin of this region of the head must not be confounded with the upper lip, with which it has nothing to do. The maxillary por- tion of the upper lip is, in fact, represented only by a fold of the integument, which begins on the outer side of the anterior nostril, and extends back to the angle of the gape, where it passes into the lower lip. The preemaxillary, or internasal, portion of the upper lip is represented by a delicate fold of the integument, disposed in a transverse arch in front of the vomerine teeth, which it separates from the inner boundary of the anterior nares. ‘The outer and posterior portion of the lower lip is produced into a free process, which is folded back against the jaw, and extends for about two thirds of the distance from the angle of the mouth to the symphysis, ending by a rounded free edge.

* “Description of Ceratodus,” Phil. Trans. pt. ii, 1871,

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 25

Thus the anterior nares can in no sense be said to open into the cavity of the mouth, inasmuch as they lie outside the preemaxillary portion of the upper lip, and are not enclosed by the maxillary por- tion of that lip. They are not even placed between the upper and the lower lips, inasmuch as the vaulted flap, on the underside of which they lie, is not the upper lip, but the anterior part of the head.

In Lepidosiren, the anterior nares are closer to the anterior margin of the head than in Ceratodus, and the preemaxillary lip is repre- sented only by a papillose ridge, in which the integument of the underside of the head, between the anterior nares, terminates pos- teriorly. Otherwise the disposition of the nostrils is quite as in Ceratodus ; and when the mouth is shut, the nostrils open on the underside of the head, in front of it and of the rudimentary pre- maxillary portion of the upper lip.

The disposition of the nasal apertures in the Dipnoi is essentially Selachian *. In the common Dogfish (Seyliium), for example, the anterior contour of the head answers to the anterior contour of the head of Ceratodus. The mandibular and maxillary lips are similarly disposed ; and the external nares are placed on the sides of the head in a similar position. But the premaxillary part of the upper lip is much larger and more prominent; and its outer edges (septal ale), instead of being continued into the maxillary lip, to form the floor of the nasal passage, are separated from it by a fissure, which commu- nicates with the nasal cavity. ‘This fissure is overlapped by the septal alee; and thus an incomplete nasal passage, which opens pos- teriorly into the cavity of the mouth, is constituted.

Still more instructive is the comparison of the nasal passages of Ceratodus with those of Cestracion and Chimera. In Cestracion, the external nostrils lie just outside the mouth, the lower lip coming into contact with the maxillary and przmaxillary portions of the upper when the mouth is shut. The anterior end of the maxillary lip is folded in, and passes into the external part of the ala nasi, which has a thickened edge, and ends in a continuation of the free fold of the lip. The inner ala nasi is the outer part of the internasal or pree- maxillary part of the upper lip. It also ends in a free edge, which is rolled inwards. The septal ala and the maxillary ala do not unite ; but a groove is left between their convex edges, which answers to part of the groove which leads from the nose into the mouth in Dog- fish and other Plagiostomes. But the greater part of this groove is represented by a canal formed by the convoluted septal ala, which is open on its dorsal aspect, and communicates, in front, with the cavity of the olfactory sac. Behind, the free edge of the septal ala has a curious fringe; and when the mouth is shut, this fringe overlaps the edge of the mandible. The free edge of the septal ala bounds a large opening, the posterior nostril, which is situated, as in Cera- todus, at the point of junction between the vomerine and the palatine teeth. Consequently, when the mouth is shut, there is a free passage for water through this incompletely closed nasal canal.

* See the excellent observations of Gegenbaur, ‘ Kopfskelet der Selachier,’ p. 224 et seq.

26 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

An arrangement of a very similar character exists in Chimera. Here the nasal septum is very narrow, but widens out below, where, as the premaxillary lip, it overlaps the vomerine teeth. The free edge of the septal ala is curved in, as in Cestracion. Meeting it is an inward process of the maxillary lip, which abuts against the septal ala in the same way as the maxillary ala does in Cestracion. QOut- side this, again, is another flap-like process of the maxillary lip, which overhangs the foregoing when the maxillary lip is in place. Between the preemaxillary lip and the maxillary lip is the nasal pas- sage, open ventrally as in Cestracion; and an interval between the vomerine and palatine teeth above and the mandibular tooth below (the posterior nostril) places this passage in free communication with the oral cavity. _

It is obvious that if the septal and the maxillary ale in Scyllium,

Fig: 1.

Ceratodus forsteri. Dorsal view of the brain in si¢z.

Pr E, loous communis of the prosencephalon; 7%.£, Thalamencephalon; Px, pineal gland; M/E, mesencephalon (the median groove is somewhat, too strongly marked); Cb, cerebellum ; 7», tela vasculosa over the fourth ven- tricle; ¢.s.c, p.s.c, external and posterior semicircular canals; I, V, VII, 1X, X, cerebral nerves; H.O, exoccipital ossification, The general contour of the chondrocranium is given; on the right side the cartilage has been sufficiently removed to show the anastomosis of the seventh and ninth nerves, the auditory organ, and other deep-seated parts. With respect to this and the other figures, | may remark that my object has been to make accurate diagrams drawn to scale, and not pictures.

Cestracion, and Chimera united along the middle line, such a nasal passage as exists in Ceratodus would be the result. Compared with

1876.) PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 27

Ceratodus, the Elasmobranchs mentioned are hare-lipped; and as regards the position of the external nostrils, Cestracion and Scyllium are intermediate between Chimera and Ceratodus.

It may be asked, what is the use of a nasal passage and of internal nares in a purely branchiate animal? Without actual experiment it is hard to give a definite answer to this question; but I will venture upon two suggestions. In the first place, these communications be- tween the cavity of the mouth and the exterior must permit slow respiration to take place when the jaws are shut; and it is easy to imagine that this, under many circumstances, may be an advantage.

In the second place, the large olfactory sacs of these animals sug- gest that the sense of smell is of value to them; and the communi- cation of the nasal passages with the mouth must enable them to do what they could not do otherwise—namely, accelerate the rapidity of the contact of odoriferous particles with the Schneiderian membrane at will. The fish with posterior nasal apertures, in fact, can “ sniff” effectually, while that operation could only be very imperfectly per- formed by compression and dilatation of the walls of the olfactory

Fig. 2.

ME, Ch TT EO.

Pr. ee

MBP

Ceratodus forstert. Left lateral view of the brain in situ.

The details of the structure of the dorsal region of the spinal column are omitted. Ch, notochord; E.O, exoccipital ossification; P.Sph, parasphenoid; 7, vomerine teeth ; az, pn, positions of the anterior and posterior nares; Op, operculum ; /.Op, interoperculum ; Sp/, splenial, and D, dentary bones of the mandible; Mes, Meckel’s cartilage; M.B', M.b?, anterior and posterior mesobranchials ; Br. 5, fifth branchial arch; 6, nodule of cartilage, which possibly represents a rudimentary sixth arch; Py, pituitary body. The other letters have the same signification as in the preceding figure. The suprascapular bone is shown in place; and its contour is given as if the anterior part of the vertebral column were transparent.

sacs in the absence of any second opening. Probably the second opening so generally present in the olfactory sacs of the Teleostei, and the naso-palatine canal of the Marsipobranchs, have a similar

28 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

physiological significance. In Ceratodus there is the further phy- siological relation to aerial respiration ; and in all the higher Verte- brata the nasal passages are concerned in sniffing and breathing. With respect to the internal structure of Ceratodus, I shall con- fine my remarks, in the present communication, to the brain, the skull, and the pectoral limbs. Ceratodus is, in fact, the most sur- prisingly suggestive animal I have ever had occasion to study ; and the attempt to comprehend the morphological significance of the organs I have mentioned has led me so far, that I must defer the consideration of other parts of its organization to another occasion.

I. The Brain.

I had no great hope of finding the brain in a state fit for ex- amination in my specimen of Ceratodus; and in fact the cerebral substance and that of the nerves are in avery friable condition. But, by great good fortune, the pia mater is so very dense and tough, © that it has held the cerebral substance in place; and thus not only the external form, but somewhat of the internal structure of the brain could be satisfactorily determined.

Fig. 3.

Ceratodus forstert. Underview of the brain (nat. size).

I, olfactory, II, optic, VI, third nerve (?); V, VII, IX, X, roots of the tri- geminal, portio dura, auditory, glossopharyngeal, and pneumogastric nerves ; v.c, one of the lateral ventricles of the lobws communis, laid open from below.

The brain is represented from above in fig. 1, from the left side in fig. 2, and from below in fig. 3.

1876.| PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 29

‘The brain of Ceratodus nearly fills the cranial cavity, the inter- space left between it and the walls of the latter being, to a great ex- tent, occupied by a peculiar reticulated tissue. ‘The medulla ob- longata is long and slender, but widens, anteriorly, in the region of the fourth ventricle. This cavity is arched over by a ¢ela vasculosa (Tv, figs. 1 and 2), separated into two lateral convexities by a slight median depression. In front, each convexity is continued into a blind rounded cornu, which lies over the origin of the fifth and seventh auditory nerves. The two cornua diverge, and the cerebellum is continued backwards as a triangular lamella between them. The cerebellum is relatively very small, being represented merely by the thin arched roof of the anterior part of the fourth ventricle. In front of it is a rounded elevation, obscurely divided by a longitudinal depression into two. These are the only indications of the optic lobes of the mid brain, or mesencephalon. In front of this is the fore brain. The hinder division (or thalamencephalon) is narrower than the mesencephalon, and passes below into the infundibulum, which terminates in the large, oval, flattened, pituitary body (hypo- physis). This is lodged in an excavation of the cartilaginous floor of the skull representing the sella turcica.

Dorsally, the thalamencephalon is continued upwards and forwards into the subcylindrical peduncle of the pineal gland (epiphysis or conarium). ‘This is a large heart-shaped body, the base of which is turned downwards and backwards. The apex is connected by fibrous and vascular tissue with a depression in the cartilaginous roof of the skull.

Next follows the largest division of the brain, answering to the cerebral hemispheres and the olfactory lobes. The former are repre- sented by a single oval lobus communis, the middle area of the roof of which is occupied by a broad thick tela vasculosa. From the anterior dorsal aspect of the prosencephalon proceeds, on each side, the large olfactory lobe, which, flattening in front, and becoming obliquely truncated, terminates against the posterior walls of the olfactory sacs. A backward prolongation of the mesethmoid carti- lage separates the twolobes. In the lateral view of the brain (fig. 2) the manner in which the olfactory lobes take their origin from the dorsal aspect of the prosencephalon is well seen. The short and thick infundibulum, terminating in the flattened oval pituitary body, and the origins of the second, third, fifth, eighth, ninth, and tenth nerves are shown.

The ventral view (fig. 3) displays the origins of the small optic nerves (II) which arise close together from the floor of the thala- mencephalon. Whether any chiasma exists could not be ascertained.

In the middle line of its ventral aspect the prosencepbalon presents a deep longitudinal fissure, lodging anterior cerebral arteries. The walls of the fissure have been separated by turning the left division of the prosencephalon to one side; and the floor of the ventricle (v.c), which is contained in the prosencephalon, has been removed.

When the dorsal wall of the brain was cautiously laid open by a median section, it was found to contain one large ventricular cavity

30 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. ([Jan. 4,

the separation of which into fourth and third ventricles was indicated only by slight constrictions of the roof and side walls. The large ventricle of the prosencephalon is partially separated into two cham- bers by a median septum, formed by the infolding of its ventral wall ; and the spacious ventricle of each olfactory lobe opens into the dorso- lateral part of each of these chambers.

The place and mode of origin of the olfactory and of the optic nerves have already been mentioned.

The third nerve is indicated in the figure; but I am somewhat doubtful as to the nature of the cord thus marked.

No fourth or sixth nerve was observed.

The fifth arises by a single large cylindrical root just below the anterior end of the cornu of the tela vasculosa of the fourth ventricle. The seventh and eighth leave the medulla by a common root just behind this; and the roots of the ninth and tenth nerves, divided into three bundles, arise from a tract at the sides of the medulla which extends from the last to the hinder limit of the tela vasculosa, and incline obliquely backwards to their exit.

The brain of Ceratodus is very singular and interesting, inasmuch as it presents resemblances to that of the Marsipobranchii on one side, to that of the Ganoids and Amphibia on another, and to that of the Chimeeroids and Plagiostomi on a third.

As in the brain of the Marsipobranchii, the pineal gland is rela- tively very large, with its pointed dorsal end inclined upwards and forwards, and the roof of the fourth ventricle is almost entirely formed by the ¢e/a vasculosa; but, as in the Ganoidei and Am- phibia, the cerebellum is larger than in the Lampreys. ‘In Cera- todus it is similar to, though proportionally less than, that of Lepi- dosteus, and still more like that of Polypterus. In the proportions of the thalamencephalon the brain of Ceratodus resembles that of the Sturgeon and that of the Ray; while in the representation of the cerebral hemispheres, or prosencephalon, by a large imperfectly divided lobus communis, from the dorso-lateral regions of which the olfactory lobes take their rise, the brain of Ceratodus presents a feature hitherto known, so far as I am aware, only in the Plagiostomi*. Thus, in its cerebral characters, Ceratodus occupies a central place in the class Pisces.

The development of the cerebral hemispheres in Plagiostome fishes differs from the process by which they arise in the higher Vertebrata. In a very early stage, when the first and second visceral clefts of the embryo of Scyllium are provided with only a few short branchial

* So far as I can judge from the examination of a small but well-preserved specimen of Lepidosiren annectens, for which I am indebted to Mr. Sclater, the brain of this fish is similar, in all essential respects, to that of Ceratodus. The figure of the brain of Lepidosiren given by Prof. Owen in his ‘ Anatomy of Ver- tebrates’ is susceptible of interpretation in this sense. Hyrtl’s description and figure of the brain of Lepidosiren paradoxa (Abhandlungen der koniglichen bohmischen Gesellschaft, Bd. iii. 1845), on the other hand, leave me in doubt whether, apart from its curious asymmetry, the brain of this fish does or does not present important differences from that of Cerafodus and that of Lepido- siren annectens,

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 31

filaments, the anterior cerebral vesicle is already distinctly divided into the thalamencephalon (from which the large infundibulum pro- ceeds below, and the small tubular peduncle of the pineal gland above, while the optic nerves leave its sides) and a large single oval ‘ vesicle of the hemispheres.’’ On the ventral face of the integument covering these are two oval depressions, the rudimentary olfactory sacs.

As development proceeds, the vesicle of the hemispheres becomes divided by the ingrowth of a median longitudinal septum, and the olfactory lobes grow out from the posterior lateral regions of each ‘ventricle’ thus formed, and eventually rise onto the dorsal faces of the hemispheres, instead of, as in most Vertebrata, remaining on their ventral sides. I may remark that I cannot accept the views of Miklucho-Maclay, whose proposal to alter the nomenclature of the parts of the Elasmobranch’s brain appears to me to be based upon a misinterpretation of the facts of development.

Il. The Skull.

Dr. Ginther* distinguishes in the skull an “inner cartilaginous capsule and an outer incomplete osseous case, to which again some outer cartilaginous elements are appended. In the former the con-

Yeratodus forsteri. Lateral view of the chendrocranium, with most of the bones and fibrous tissues removed.

ol, position of the olfactory sac; az, pn, position of the anterior and posterior nares; @, process of the cranial cartilage, 7, between the two; 1, 2, upper labial cartilages; op, optic foramen; 4.0, antorbital process; P.O, post- orbital process; P.@, palato-quadrate process; Sq, Qu, remains of the bony plate which lies on the outer side of this process; O.C, occipital prolon- gation of the chondrocranium roofing over the branchial cavity ; D, den- tary; Ax, angular; Hy, hyoid; /op, interoperculum ; Op, operculum; R, R’, cartilages representing hyoidean rays; HM, hyo-mandibular.

fluence of cartilage is so complete, that no distinct divisions are trace- able by sutures; its parts can be designated only by reference to the locally corresponding bones of the teleosteous skull.”

Mes a Onke

32 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

This would seem to imply that the chondrocranium of vertebrated animals is formed by the coalescence of parts analogous to those which compose the bony skull of osseous fishes. As a matter of fact, how- ever, the chondrocranium is never formed of such elements, but is built up, at a very early stage of embryonic development, by the union of primitively distinct parachordal, otic, and pleural elements*, which in no way correspond with the bones of the teleostean skull. And when Dr. Giinther subsequently (/. ¢. p. 522) speaks of ‘ three groups of superficial labial cartilages,” ‘the upper labial,” the “su- praorbital,” and the ‘lower labial,” the discrimination of such car- tilages must, I think, be regarded merely as regional anatomy ; and it must not be supposed that they have any thing to do with the cartilages to which the same names are applied in otner fishes, several of which exist in Ceratodus, and will presently be described.

When the osseous and merely fibrous structures are carefully re- moved, I find that the chondrocranium (figs. 4, 2, and 7) consists of a continuous cartilaginous mass, the interorbital region of which is much narrower than any other part, produced inferiorly and laterally into two stout suspensorial or palato-quadrate processes, with the pulley- shaped ventral ends of which the strong Meckelian cartilages are articu- lated. Anteriorly the orbits are bounded by the antorbital processes (4.0), which curve downwards in front of the eye. From these ant- orbital processes the cartilage is continued forwards to form the evenly curved roof of the ethmoidal region and its coutained nasal chambers, and, bending down on all sides, ends in a free edge, which is slightly concave opposite each anterior nasal opening (an, fig. 4), and much more deeply excavated opposite the posterior nares (pa, fig. 4). The small process (a) which lies between the two excavations in question is connected by a strong fibrous band with the antorbital process (A.O), and this, by the ossified bar described by Dr. Giinther, with the postorbital process (P.O); but these structures have nothing to do with the chondrocranium. Behind the orbits, the skull suddenly widens out into two broad periotic masses, which lodge the auditory labyrinth. Anteriorly and ventrally these processes are continued into the suspensorial pillars (Qu); while behind they pass into thin but wide cartilaginous plates (O, C, fig. 4), which roof over the chambers in which the branchiz are lodged.

I thought at first that Ceratodus had no labial cartilages; but at length I discovered two small upper labial cartilages in their right places, namely in the region of the nostrils.

One of them (1, figs. 4 and 5) lies in the roof of the mouth, just in front, and on the inner side of, the posterior nasal aperture. It is fixed to the mesethmoidal cartilage (WZ./) by fibrous bands, and is broader behind than in front. The inner edge of this cartilage is concave, the outer convex, and it has a nearly horizontal direction.

The second cartilage (2, figs. 4, 5, 7) is stouter, and lies behind, and on the outer side of, the posterior nasal aperture. Its dorsal end is attached to the base of the skull and anterior part of the

* “On the Structure of the Skull &e. of Menohranchus lateralis,’ P. Z. 8. 1874.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI,. 33

palato-quadrate cartilage just above the middle of the palatine tooth. It thence descends with an outward convexity and inward concavity, and terminates in the upper lip near the angle of the mouth.

Dr. Giinther states (/. c. p. 524) that “the body of the mandible is persistent cartilage; but its entire outer and inner surfaces are covered by bone, forming an articular and a dentary piece... .. . The articular and dentary bones meet near the top of a low but strong coronoid process, and again at the symphysis, which is formed by fibrous tissue, and may easily be separated by the knife... . In front of the jaw the cartilage is expanded into a slightly concave lamella (lower labial cartilage).”’

Ceratodus forsteri. Underview of the skull, showing the yomerine teeth ( V1), the palatine teeth, the mesethmoid cartilage (J/./), and the upper labial cartilages (1, 2) in place. The dotted lines An, p.n indicate the form and position of the anterior and the posterior nares.

I find a persistent Meckelian cartilage, such as that here described ; but as, after careful removal of the ensheathing bones, I have been unable to discover any separation between this lamellar expansion and the rest of the cartilage, I am in doubt whether the lamella represents the lower labial cartilage or not. The analogy of the Frog, however, leads one to suspect that distinct lower labial carti- lages may exist in the young Ceratodus.

Dr. Giinther does not mention a third ensheathing bone (figs. 2 and 4, D) which is united by suture with the other two, and lies on each side of the symphysis on the ventral face of the mandible. It is a flat plate, of a triangular form, with a thick rugose inner edge for the attachment of the symphysial ligament. Its posterior edge is thin and concave; its external edge is also thin and overlaps the bone termed “articular”’ by Dr. Giinther, uniting with it by a squamous suture. The outer half of its dorsal aspect is smooth, and helps to support the ventral face of Meckel’s cartilage ; the inner or symphysial half pre- sents a broad rough triangular surface, which extends on the imner

Proc. Zoou. Soc.—1876, No. III. 3

34 PROF. T. H, HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

side of the symphysial end of Meckel’s cartilage, and unites with a corresponding surface furnished by the expanded symphysial end of the bone, termed “dentary”’ by Dr. Giinther. I cannot doubt that this bone is the representative of the true ‘‘dentary” element ; nor is there any question in my mind that Dr. Ginther’s “ dentary”’ is the true ‘splenial’”’ element, while his articular answers to the “angu- lar’? piece of the vertebrate mandible. In the attachment of the tooth to the splenial, and not to the dentary, element, Ceratodus presents an interesting and important feature of resemblance to Szren and to larval Salamanders on the one hand, and, on the other, to Polypterus.

The splenial element in this Ganoid resembles that of Ceratodus, not only in bearing teeth, but in form, position, and relative size. In a young specimen of Polypterus I find that the splenial does not extend continuously to the symphysis, but that, between its anterior termination and the latter, there are two short and broad bony plates developed in the fibrous tissue which overlies Meckel’s cartilage ; these bear teeth, and correspond with the expanded symphysial end of the splenialin Ceratodus. Polypterus has a true articulare, from which Meckel’s cartilage is continued. The angulare is much shorter, and the dentale much longer than in Ceratodus.

The hyoidean and opereular apparatus present characters of sin- gular interest. Dr. Giinther says that “on the hinder side of the tympanic pedicle*, near its base, there is a small round tubercle, for the suspension and articulation of the hyoid areh (pl. xxxiv. fig, 3,0),

I presume that this ‘“‘small round tubercle”’ of the suspensorial expansion of the cranium is the small cartilage marked #.J/ in figs. 4 and 6, But this is neither a process of the suspensorium, nor does it articulate with, nor take the principal share in, suspending Hy, which is Dr. Ginther’s ‘* hyoid arch.”

In fact it is, as fig. 6 shows, a distinct, though small, four-sided, flattened cartilage, the anterior and ventral angle of which is produced into a short conical process (Sy). Its anterior edge is firmly united with the skull, just where the cranium proper passes into the sus- pensorium, At this point there is a triangular vacuity filled with fibrous tissue, through which the posterior division of the seventh nerve passes (figs. 1 and 6, VII). ‘The outer face of the cartilage is loosely connected with the operculum (Op); and the conical process (Sy) is imbedded in the dorsal and posterior part of the powerful ligament (A.s) (corresponding with the hyosuspensorial ligament in Menobranchust) by which Hy is mainly kept in place.

It is obvious that this little cartilage is the homologue of the hyo- mandibular element of the hyoidean arch of other fishes, the small conical process being the rudimentary symplectic, and, therefore, that

* It is surely to be regretted that any writer of authority should retain the misleading name of “tympanic pedicle” for a part the total distinctness of which from the “tympanic bone” of the higher Vertebrata has now been so copiously demonstrated,

+ P, ZS. 1874, pl. xxix. figs. 1 and 2.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 35

it is itself the dorsal element of the hyoidean arch, attached in its normal position, as its relations to the seventh nerve show. The hyoidean cornua are very strong, and consist of a cartilaginous axis almost completely ensheathed by bone. The dorsal end of each is

Ceratodus forsteri. Inner view of the right hyoidean arch (Hy), with the oper- cular apparatus and part of the suspensorium and of the mandible.

H.M, hyomandibular cartilage; Sy, its symplectic process; Op, operculum’;

Lop, interoperculum ; Ff, Ff’, cartilaginous rays attached to the inner face

of the operculum and interoperculum ; VII, exit of the posterior division of

the seventh nerve; 4.s, hyosuspensorial ligament (immediately beneath it is the mandibulo-hyoid ligament).

attached by the strong hyo-suspensorial ligament aforesaid to the suspensorium; but another very strong round ligament (answering to the mandibulo-hyoid ligament of Menobranchus*) counects the dorsal end of the hyoidean cornu with the angle of the mandible (figs. 4 and 6).

Thus the hyoidean arch of Ceratodus strikingly resembles that of a Plagiostome on the one hand, and that of an Amphibian on the other, And the small hyomandibular presents a form and connexions which are strikingly similar to those of the suprastapedial cartilage in the Sauropsidat, which, on a former occasion, I showed to be the summit of the hyoidean arch and the homologue of the mammalian incus.

In describing the operculum Dr. Ginther says (/.c. p. 525), «A small movable piece of cartilage is found inside of the articulary groove of the opercle (pl. xxxiv. figs. 2 and 3, 4): it is a rudiment of the preeoperculum.”’

Neither the figures referred to nor the account given enable me to be certain that they apply to the cartilaginous structures I am about

* P.Z.S. 1874, zbid.

+ “On the representatives of the Malleus and Inous of the Mammalia in other Vertebrata,” P. Z. 8S. 1869,

3*

36 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

to describe, and which are to be found not only on the inner face of the operculum, but on that of the interoperculum*.

On the inner side of the former and projecting beyond its free edge is a curved band of cartilage divided into several portions‘. One of these, that nearest the hyomandibular, is conical and bent at an angle to that which follows it. The terminal plate is broad and crescentic, and, on one side, was subdivided towards its free edge. On the inner face of the posterior end of the interopereuluin (L.op.) there is an oval cartilage surrounded by eight or nine smaller nodules.

These cartilages represent the cartilaginous branchiostegal rays of Plagiostomes, which are often subdivided into two groups—a dorsal group attached to the hyomandibular, and a ventral group to the cornual division of the hyoid areh.

The preoperculum of Fishes and the sqguamosal of the higher Ver- tebrata are represented by the bone Sq, termed ‘tympanic lamina’”’ by Dr. Giinther. I have marked the lower piece, which was distinct on the specimen represented in fig. 4, Qu; but in another specimen I can find no subdivision, and I am disposed to think that the divi- sion arose from an accidental dismemberment of a squamosal (or preoperculum) corresponding with that of Menobranchus (P.Z.S. 1874, pl. xxix. fig. 1, Sq), and that there is no true quadrate in Ceratodus. I can discover no ossification of the substance of the articular extremity of the suspensorium, such as occurs in the Am- phibia. The pterygopalatines and the vomers, which last are repre- sented only by the bases of the two vomerine teeth, are similar in their form and relations to the corresponding bones of Urodele Amphibia.

With respect to the branchial apparatus, Dr. Giinther (J. c. p. 526) says that it “does not differ from that of Teleostean fish, but is entirely cartilaginous. There are five branchial arches, the last rudimentary and attached to the base of the fourth. There is no peculiar modification of any part of this apparatus; and the middle pieces have the usual groove for the reception of the vessels and nerves.”

I find that each of the anterior four branchial arches consists of a long ventral and a short dorsal piece of cartilage: the former pieces are united by ligament at their ventral ends, the third and fourth curving forwards in this part; they are connected by joints sur- rounded by ligaments with the dorsal pieces (fig. 2). In the median

* Dr. Giinther terms the bone here named interoperculum, “ suboperculum.” He says (/. c. p. 525) that to the lower edge of the operculum ‘is attached by fibrous tissue the long styliform swboperculum, terminating at a considerable distance from the mandibulary joint.” It is quite true that the bone in ques- tion is thus attached to the operculum ; but a much more important connexion takes place between its ventral end and the angle of the jaw, by means of strong ligamentous fibres which run into the hyomandibular ligament. It thus more closely resembles the interoperculum of Teleosteans than it does the sub- operculum.

+t Ina specimen of the skull of Ceratodus, for which I am indebted to my friend Mr. F. M. Balfour, the curved band of cartilage of the operculum is not subdivided, and the interopercular cartilages are divided less regularly and differently on the two sides,

1876.| PROF. T. H. HUXLEY ON CERATODUS FORSTERI. oN,

ventral line, between the ends of the ventral pieces, lie two cartilages— an anterior elongated and spindle-shaped (J7.B'), which is connected by a strong ligament with the median piece of the hyoid arch, and a posterior rounded nodule (M. B*) at some distance from the foregoing. The fifth arch consists of a single piece of cartilage curved forwards and united with the principal branchial of the fourth arch, both above and below; in front of it, close to the ventral end of the fifth arch, was a small nodule of cartilage, which is probably a rudimen- tary sixth arch (6).

C ay ¥ Ceratodus forsteri. Dorsal aspect of the skull,

a, the anterior end of the chondrocranium; %, the antorbital process of the chondrocranium ; ¢, its suprabranchial expansion; d, lateral elevations of the occiput ; and e, median ridge, with the surface for the attachment of the anterior fin-ray; f, articular surface for the second fin-ray; A, anterior median bone; £, posterior median bone; C, inner lateral bone; C’, distinct ossification on the posterior extremity of this bone; D, outer lateral bone (squamosal); £, a separate ossification on the left side; Op, operculum ; Or, orbit; Sb.o, suborbital bones; 2, the posterior upper labial cartilage.

As Dr. Giinther has pointed out, the osseous shield which covers the dorsal aspect of the skull consists of two median bones (fig. 7, A, B), one anterior and one posterior, which he terms ‘‘ethmoid”’ and ‘‘scleroparietal,”’ and of two pairs of lateral bones, the “frontals”’ internally (fig. 7, C) and the “tympanic lamin ”’ externally (fig. 7, D). In my specimens the anterior half of the anterior median bone (A) has a different shape from that given in Dr. Giinther’s plate xXxxiv. fig. 1, and its margins are very well defined. Moreover, in

38 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

one specimen, the hinder end of each inner lateral bone is completed by a distinct ossification (C’). There is also a separate ossification (£) on the left side, on what corresponds with the front part of the outer lateral bone on the right side. Doubtless these bones are subject to much individual variation.

The fibrous band which extends, below the eye, between the ant- orbital process and the ventral end of the suspensorium contains three suborbital bones. The anterior of these, trihedral, is connected by its broad base with the antorbital process ; the middle bone is slender and elongated ; the posterior is broad, flattened from side to side, and its hinder edge is fixed by ligamentous fibres to the outer face of the suspensorium and of the squamosal.

The dasal bone of Dr. Giinther is the parasphenoid. It extends backwards, beyond the limits of the proper cranium, into the region of the vertebral column, to a point just beyond the attachment of the third pair of ribs. But there is at least one vertebra in front of that which bears the first pair of ribs. In Ceratodus, as in the Sturgeon and other Gancids, several anterior vertebrae have coalesced with one another and with the skull; or, probably, it would be more accurate to say that the investing mass of the notochord has not become differentiated into vertebree for this extent. Nevertheless the pos- terior boundary of the skull can be strictly defined by the interspace between the exit of the pneumogastric and that of the next following, or first spinal, nerve.

It is to the outer surface of this interspace that the anterior edge of the “suprascapular’’ element of the pectoral arch is fixed by strong ligamentous fibres (fig. 2). Just m front of the boundary between the skull and the vertebral column, and therefore in the side walls of the former, there lies, deep in the substance of the cartilage, a hollow cone of bone (#.0) It is wider above and externally than below and internally, where its end lies above the notochord. This appears to be an exoccipital ossification, such as is to be found in greater state of development in Lepidosiren, Polypterus, and Meno- branchus.

The skull of Ceratodus is, as might be expected (and as Dr. Gunther has pointed out), extremely similar to that of Lepidosiren. In fact, beyond differences in the proportions of its various parts, the more extensive fenestration of the roof of the olfactory capsules in Lepidosiren, and the absence, so far as my investigations have yet gone, of the hyomandibular cartilage in the latter genus, the carti- laginous elements of the skull are the same in the two cases.

As to the superadded bones, the parasphenoid, the rudimentary vomers, and the pterygopalatine plates correspond in the two genera. The exoccipitals are much larger in Lepidosiren. The descending process or preeopercular part of the squamosal is best developed in Lepidosiren, whilst its dorsal part (proper squamosal) is larger in Ceratodus.

In both, there are two opercular bones, an operculum and an inter- operculum ; and in Lepidosiren, as in Ceratodus, there are cartilagi- nous plates attached to the inner faces of these bones.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 39

The branchial apparatus of Lepidosiren differs from that of Cera- éodus mainly in the greater number of complete branchial arches.

It can hardly be doubted that the bone D of Ceratodus is repre- sented, though incompletely, by the supraorbital of Lepidosiren, while the bony nasal shield of the latter corresponds very closely with the anterior median bone (A) of Ceratodus. The posterior boundary of the bone, however, lies further back in Ceratodus than it does in Lepidosiren. The argument of Dr. Giinther that the posterior median bone (B) in Ceratodus is not the homologue of the parieto- frontal of Lepidosiren, because it lies above the muscles, while the latter is situated beneath them, is weighty against the identification of the bones in question ; and, in other respects, the parieto-frontal of Lepidosiren is very unlike the “ scleroparietal’’ of Ceratodus.

When the comparison of the cranial and facial bones of Ceratodus with those of the Vertebrata is extended beyond the limits of the Dipnoi, the determination of their homologues is beset with many difficulties. Polypterus has an anterior and a posterior median shield in the roof of the skull, which at first seem to correspond with those of Ceratodus; these shields are each formed by the union of two bones, which are evidently comparable to the frontals and parietals of the higher Vertebrata, while the frontals unite with a pair of broad nasals which cover the olfactory sacs. The apices of the posterior triangular edges of these bones reach back to near the level of the middle of the orbits; and the frontal bones are continued forwards on each side of them. Between the two nasal bones there is a median ossification which les upon the mesethmoidal cartilage and spreads out in front, ending by a broad edge which articulates with the prae- maxillee.

The median bone, the piscine ‘ ethmoid,’’ occupies the same position as the anterior median bone of Ceratodus would do if the ethmoidal region were reduced to the proportions it has in Poly- pterus. ‘Therefore, from this point of view, the determination of the bone as “ethmoid”’ by Dr. Gunther seems fully justifiable; and the inner lateral and the median posterior bones would seem to represent the frontal and parietal bones of Polypterus.

On the other hand, the many points of resemblance between Cera- todus and the Amphibia suggest the comparison of the anterior and posterior median bone to the frontals of Menobranchus, and of the inner lateral bones to the parietals of this Amphibian. The forward extensions of the latter, at the sides of the frontals, are especially noticeable in comparison with the anterior extremities of the inner lateral bones of Ceratodus. On the whole, I am inclined to think that Polypterus is the better guide in the interpretation of the cranial bones of Ceratodus, though the difference between the bones of Ceratodus and those of the Crossopterygian ganoids, all of which are readily reducible to the Polypterine type, is very considerable.

In other respects the skull of Cerotodus finds its closest parallel among the Amphibia, especially such Urodela as Menobranchus*, and the Anura in their tadpole state.

* See P. Z. 8S. March 17, 1874.

40 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

I have already indicated the chief points of resemblance to the amphibian skull, and need not recapitulate them here. The most important feature is the manner in which the mandibular arch is connected with the skull.

The part of the palato-quadrate cartilage which is united with the skull, between the exits of the fifth and second nerves, answers to the ‘pedicle of the suspensorium” of the amphibian, while its backward and upward continuation onto the periotic cartilage corre- sponds with the otic process. As in the Amphibia and in the higher Vertebrata, the mandibular arch is thus attached directly to the skull by that part of its own substance which constitutes the suspensorium. It may thus be said to be autostylic.

Among fishes, the only groups which possess an autostylic skull, or in which the dorsal end of the mandibular arch is continuous with the cartilage of the brain-case, are the Chimeeroids and the Marsipo- branehii.

In Chimera, the general form and connexions of the palato-quadrate cartilage are the same as in Ceratodus; but it differs from that of Ceratodus as that of the tadpole differs from that of a young Frog, or as that of Menobranchus differs from that of Menopoma; that is to say, the articular condyle is situated far more forward, and the gape is, in consequence, relatively shorter in the former than in the latter. There are the same large olfactory capsules in both cases. In Chimera, however, these project beyond the termination of the ethmoidal cartilage, while in Ceratodus the latter projects beyond the olfactory capsules, which are more lateral in position, more elon- gated, and, in accordance with the general form of the head, much more depressed.

Just as in Ceratodus, the palato-quadrate cartilage of Chimera bears two teeth marked with radiating ridges, while two others, the vomerine teeth, are supported by the ethmoidal cartilage in front of these; and in both cases there is a tooth with radiating ridges on its surface in each ramus of the mandible.

In the disappearance of the notochord and the articulation of the skull with the anterior coalesced vertebree, the skull of Chimera pre- sents a higher degree of differentiation than that of Ceratodus; while it is needless to speak of such aberrant peculiarities as its supracerebral interorbital septum, or the vast crest into which the skull is raised above the anterior part of the brain-cavity. In other respects, how- ever, as in the inclination of the axis of the suspensorium already noted, the skull of Chimera presents lower characters than that of Ceratodus. Among these may be reckoned the great size of the upper and lower labial cartilages and the condition of the hyoidean arch, which, except in size and some peculiarities of form, is altogether similar to the four branchial arches which follow it. Like them, it terminates, dorsally, in a flat, expanded, triangular piece, which is connected with the superjacent floor of the skull by muscles and ligaments, but by no direct articulation. The dorsal pieces of the succeeding branchial arches have the same form and attachments, aud unite with the ventral segments at a sharp angle. These angles

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI, 41

are all connected together by a strong ligament, which is continued to the pectoral arch. Moreover a small styliform cartilage passes from the last angle to the pectoral arch, and is connected with the dorsal end of the fifth branchial arch. It appears to represent the dorsal element of that arch.

Johannes Miiller, fully appreciating the importance of the differ- ences between the skull of the Chimeroids and those of other ** Klasmobranchii,”” and sagaciously remarking that ‘‘the skull of Chimera is most like that of a tadpole”*, was thereby led to separate the Chimeeroids as a suborder of the Elasmobranchii under the name of Holocephali. It appears to me that he might have been justified in going still further; for, considering, in addition to the cranial characters, the structure of the vertebral column and of the branchie, the presence of an opercular covering to the gills, the peculiar den- tition, the almost undeveloped gastric division of the alimentary canal, the opening of the rectum quite separately from and in front of the urinogenital apertures, the relatively small and simple heart, the Chimeeroids are far more definitely marked off from the Plagio- stomes than the Telecstei are from the Ganoidei.

In ail other Fishes, except the Marsipobranchii, the mode of con- nexion of the mandibular arch with the skull is different from that which obtains in the Chimeroids and the Dipnoi. The palato- quadrate cartilage is no longer continuous with the chondrocranium (though the bony elements of that arch may unite suturally with those of the skull, as in the Plectognathi), but is, at most, united with it by ligament. Moreover the dorsal element of the hyoidean arch, or the hyomandibular, usually attains a large size and becomes the chief apparatus of suspension of the hinder end of the palato- quadrate cartilage with the skull, Skulls formed upon this type, which is exemplified i in perfection in Ganoidei, Teleostei, and ordi- nary Plagiostomes, may therefore be termed Ayostylic.

But though the typical forms of autostylic and hyostylic skulls, as exemplified, e.g., by a Sturgeon, a Pike, and a Dogfish or Ray, on the one hand, and Chincie. Ceratodus, and Menobr anchus on the other, are thus widely different, certain Plagiostomes present a condition of the cranium which tends to connect ‘the two by a middle form, which may be termed amphistylic.

In the amphistylic skull the palato-quadrate cartilage is quite distinct from the rest of the skull; but it is wholly, or aloe wholly, suspended by its own ligaments, the hyomandibular being small and contributing little to its support. The embryo amphibian is am- phistylic before it becomes autostylic ; and, in view of certain palzeon- tological facts, it is very interesting that the link which connects the ape with the ordinary Selachian skull is that of Ceséracion fig. 8 if ie palato-quadrate cartilage of Chimera were membranous in the centre, as it is in the tadpole, and if along three lines radiating from this centre the cartilage were converted partly into fibrous tissue and partly into a true joint, the result would be to produce a palato-

* ¢Vergleichende Anatomie der Myxinoiden,’ erster Theil, p. 150.

42 PROF. T. H. HUXLEY ON CERATODUS FORSTER]. [Jan. 4,

quadrate apparatus such as that exhibited by Cestracion. The huge palato-quadrate cartilage (Pl, Qu) of Cestracion is united with the skull in the preeorbital region by a joint, and in the orbital region by fibrous tissue, and answers to that part of the palato-quadrate cartilage of Chimera which lies between the nasal capsule and the mandible.

Fig. 8.

Meck

Cestracion philippi. Left lateral view of the skull.

a, occiput; >, postorbital process; c, ¢’, antorbital process; d, anterior end of the chondrocranium ; o/, olfactory capsule; O¢.p, otic process, or spiracular cartilage; Sp, place of the spiracle; H.M, hyomandibular cartilage; Qu, articulation of the palato-quadrate cartilage (27, Qw) with the lower jaw (Meck); p, part of the palato-quadrate arch which answers to the pedicle of the suspensorium in Amphibia ; Hy, hyoid ; I, foramen for the optic, and V, for the trigeminal nerves; 1, 2, 3, 4, the upper and lower labial cartilages ; 5, a small cartilaginous style attached by ligament to the mandibular cartilage,

The small cartilaginous plate (O¢.p), which is connected only by ligament with the periotic cartilage above and with the quadrate below, answers to the ofic process of the Frog’s suspensorium. This cartilage lies in the front wall of the spiracle, which in Cestracion is situated low at the sides of the head, nearly in a line with the bran- chial clefts, or in the position which it occupies in foetal Selachians. Moreover this so-called spiracular cartilage bears a rudimentary gill and is so far comparable to any of the branchial arches*.

In possessing this permanent mandibulo-hyoid cleft, or spiracle, which is the homologue of the tympanic cavity and Eustachian tube of the higher Vertebrata, and in the permanence of its rudimentary

* Gegenbaur considers the spiracular cartilage to be a ray of the mandibular arch.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 43

branchia, Cestracion exhibits a lower stage of organization than Chimera, in which, as in Ceratodus, the mandibulo-hyoid cleft has disappeared. On the other hand, the hyoidean arch presents a form intermediate between that of the ordinary Selachians and that of Ceratodus and Chimera. It is stout; and its dorsal element, still retaining a little of its original form, but much thicker and more cy- lindrical, is no longer united with the skull by ligament and muscle merely, but articulates with a process of the underside of the periotic capsule. Moreover its distal end is connected by strong ligamentous fibres with the posterior end of the palato-quadrate cartilage and with an inward process of the articular end of the mandible (the sustenta- culum of Gegenbaur).

In fact, the ‘‘epibranchial”’ of the hyoidean arch of Cestracion is just beginning to take on a new function, that of suspending the palato-quadrate cartilage and mandible to the skull. It is a true hyomandibular, though small and insignificant relatively to what it becomes in other Plagiostomes, in Ganoids, and in Teleostei.

Had I been acquainted with the skull of Cestracion in 1858, I should have been spared the hesitation which I then felt* as to iden- tifying the hyomandibular of Fishes with the summit of the hyoidean arch, and which has subsequently been removed by abundant evi- dence published by Mr. Parker and myself.

In the general form of the skull, the position and proportions of the olfactory capsules, and the characters of the principal labial and alinasal cartilages, Cestracion has a stronger resemblance to Chimera than is exhibited by any other Plagiostomes; and I take it to be one of the lowest of Selachian skulls.

I am aware that in expressing this opinion [ am diametrically op- posed to Gegenbaurt, whose elaborate study of the Plagiostome skull entitles his opinion to the greatest weight, and who regards Cestra- cion as possessed of one of the highest of skulls in its group, while Heptanchus and Hexanchus have the lowest.

There is a certain ambiguity about the terms “highest”? and “lowest; but if. by the former we understand the most extreme modification of the hyostylic type of skull characteristic of the group, then I should have no hesitation in regarding the skulls of the Rays as the highest of Plagiostome skulls, while Cestracion represents a low form of the autostylic type.

Notidunus, on the other hand, appears to me to have an essentially low form of skull, so far as it is more completely amphistylic than any ordinary Plagiostome; but on this low form is superinduced a modification by which it approaches the higher autostylic skull. This is the union of the palato-quadrate arch with the postorbital

* Croonian Lecture, 1858, and Lectures on the Theory of the Skull, 1864. See also ‘‘ On the Malleus and Incus,” P. Z. 8. 1869; ‘Manual of Vertebrate Ana- tomy,’ 1871, p. 85; and Mr. Parker’s “Memoir on the Development of the Salmon,” Phil. Trans. 1872.

+ ‘Das Kopfskelet der Selachier,’ p. 60. In controverting the opinion of Professor Owen that the Cestracton is less advanced in cranial development than

Squatina, Gegenbaur observes, ‘So mochte ich gerade das Gegentheil behaupten, und nicht etwan bloss beztiglich der Basalverhaltnisse des Craniums.”

44 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

process of the skull—an articulation which, in Prof. Gegenbaur’s view, represents the primitive attachment of the mandibular arch, but, in my apprehension, is an altogether secondary connexion.

I am indebted to Dr. Giinther for a feetus of Notidanus (Heptan- chus) cinereus in excellent condition ; and the examination of the skull (fig. 9), which presents all the characteristic features of the adult*,

has confirmed the suspicion which I previously entertained, that the

Ae UEP &

/ Hy x Ik Mele i Notidanus cinereus. Weft lateral view of the skull.

Letters as in the preceding figures. VII, the posterior division of the portio dura.

skull of Not¢idanus, though fundamentally of a low type, is greatly modified so far as the jaws are concerned. What first led me to suspect that this might be the case was the backward position of the articular end of the suspensorium and the relative length of the gape— features in which the skull of Notidanus differs from that of ordinary Selachians as an old frog differs from a young one.

The palato-quadrate cartilage of Notidanus has an inward process (p), which lies in a strong ligamentous band, by which it is attached to the skull between the optic and trigeminal foramina. ‘This an- swers to the pedicle of the suspensorium in the Amphibia. From this point the palato-quadrate cartilage extends backwards, as a laterally compressed deep plate, the posterior and inferior extremity of which gives attachment to the mandible. The dorsal and anterior angle of this plate is attached only by ligament to the postorbital pro- cess, in the foetus, but appears to articulate therewith in the adult. I think that there can be no doubt that this upward and backward extension of the palato-quadrate cartilage answers to the o¢ie process in the amphibian. It has similar relations to the posterior division of the seventh nerve ; and between it and the hyoidean arch lies the

* See Gegenbaur, op. cit.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 45

spiracle, in correspondence with its homologue the tympano-eusta- chian passage. The dorsal and posterior edge of this process no less clearly corresponds with the spiracular cartilage in Cestracion, other- wise absent in Notidanus. The hyoidean arch is attached to the periotic region of the skull. It is very slender ; and though closely bound by ligament to the mandibular arch, close to the articulation of the mandible, it can contribute little or nothing to the support of the latter. Remove the great otic process of the palato-quadrate arch of Notidanus, and bring its quadrate end further forward, and the result would be a typically amphistylic skull, such as exists in the larval Siredon and Triton*.

The relations of the skulls of Notidanus, Cestracion, and Cera- todus may be thus expressed :—

Notidanus most nearly approaches the amphistylic skull, such as exists in all the autostylic Vertebrata in the embryonic state; but it is considerably altered by the development of a great otic process from the mandibular arch.

In Cestracion the palato-quadrate has become massive, and, in the region of the pedicle, is firmly united with the skull, while the otic process is a separate cartilage, connected only by ligament with the postorbital process above and with the palato-quadrate below.

In Ceratodus the palato-quadrate has coalesced with the skull both by its pedicle and by its otic process; and the same change occurs in the autostylic skulls of the Amphibia.

In the ordinary Plagiostomes, on the other hand, the palato- quadrate becomes smaller and more freely united with the skull. The otic process (=spiracular cartilage) is smaller, and the hyomandi- bular takes a larger and larger share in suspending the mandibular arch to the skull, which is therefore eminently hyostylic.

Turning now to osseous fishes, the skull which presents the nearest resemblance to Ceratodus is that of Polypterus. This will be obvi- ous to any one who studies the excellent description of the chondro- cranium of this fish given by Dr. Traquair.

But in the character of the palato-quadrate arch and the great relative size of the hyomandibular, the skull is as thoroughly and completely hyostylic as is that of -any other existing Ganoid or Teleostean.

Thus, having regard only to the structure of the cranium, the relations of Ceratodus may expressed as follows :—

Amphibia. __——Ganoidei. _—_— Teleostei. Pep i Ps CERATODUS.—_ ~ ——— Cestracion. Raia. Chimera. Notidanus. Se VY ve ~ AUTOSTYLICA. AMPHISTYLICA. HyYostTyYLica.

* P.Z.S. 1874, pl. xxxi. figs. 1 & 2. + “The Cranial Osteology of Polyptervs,”’ Journal of Anatomy and Physi- ology, 1870.

46 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

Til. Tre Pectoral Limb.

In the memoir cited, Dr. Ginther describes the limbs of Cerafodus and their skeleton as follows :—

«The limbs consist of two pairs of paddles, similar in appearance to the termination of the tail; viz. a longitudinal axis, formed by the endoskeleton and muscles and covered with scales, is surrounded by a broad rayed fringe. These paddles are structurally identical with the fins of Lepidosiren; only the axis and also the fringe are much dilated. ‘The pectoral and ventral paddles taper toa fine point, the former being longer than the head, the latter rather shorter. The ventral paddles are inserted at a short distance in front of the vent’ (p. 515).

«The paddle is joined to the scapular arch by an elongate, flattish, slightly curved cartilage ; its proximal end has a glenoid cavity, fitting into the humeral condyle ; the joint is simple, free, allowing of a considerable amount of motion, its parts being held together by a ligament fastened round its circumference. ‘This is the only true joint in the limb, all the other parts being fixed to one another by connective tissue. I consider this cartilage to be the forearm ; a horizontal section along its longitudinal axis does not show any pri- mary division. The next following cartilage forms the base of the paddle ; although externally it appears as a single flat, broad, short piece, unevennesses of its surface indicate that several primary pieces are coalesced in it.

‘‘T am confirmed in this view by a horizontal section, m which the lines of the former divisions are preserved in the shape of tracts of a white connective tissue. Three such divisions may be distin- guished, corresponding to the three carpals of most Plagiostomes *. If this determination is correct, then the antibrachial cartilage just described is not represented in that order.

«The remaining framework of the paddle shows an arrangement unique among the Vertebrata. From the middle of the basal carti- lage a series of about twenty-six subquadrangular pieces takes its origin, forming a longitudinal axis along the middle of the paddle to its extremity. The pieces become gradually smaller, and are scarcely distinguishable towards the end of the paddle. On the two posterior corners of each piece a branch is inserted, running ob- liquely backwards towards the margin of the fin; the branches of the first eight or twelve pieces are three-jointed, the remainder two- jointed, the last having no branch at all. Slight irregularities, such as the origin of two branches from one side of a central piece, occur, as also several four-jointed branches being inserted immediately on the basal cartilage ” (pp. 532-3).

In general, this description suits the pectoral fins of the specimen I have described very well. Mine, however, has only twenty median cartilages. All but the very last bear lateral rays; but towards the distal end of the fin these become minute, and consist of a single piece. Moreover the distal joints are much more slender, especially

* Pro-, meso-, and metapterygium of Gegenbaur.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 47

the last. A more important point is that the second shows no trace of such divisions as those described by Dr. Gunther. To make sure of this I made a thin microscopic section of this cartilage on the right side, and thereby satisfied myself of the homogeneity of the cartilage of which it is composed.

I find no true joint between the proximal median piece and the scapular arch, the connexion between the two being effected by a solid fibrous mass.

Again, the ‘‘slight irregularities’’ in the distribution of the rays, in respect of the median pieces, of which Dr. Giinther speaks, are constant peculiarities of no small importance. This becomes obvious when the fin of Ceratodus is compared with that of other fishes. But before proceeding to this point L must make a few remarks on the normal and primitive position of the vertebrate limb, and on the changes from that normal position which take place in fishes on the one hand, and the higher Vertebrata on the other, as, for want of attending to this fundamental matter, grave errors have crept into the interpretation of the parts of the limbs of different vertebrates.

The fins occupy the normal position in such a fish as Seyllium, When the axis of the body is horizontal the plane of the fin is also horizontal. Its upper surface is covered by a continuation of the dorsal integument, and its lower surface by that of the ventral side of the body. The distinctive spotting of the dorsal aspect in the Dogfish makes this very plain; therefore, to adopt the nomenclature which I some time ago proposed, the convex thick edge of the fin is preeaxial, while its concavo-convex thin edge is postaxial, and its two aspects look respectively upwards and downwards.

In Ceratodus, however, the fin has undergone a rotation upon its axis, in virtue of which its proper ventral surface looks more or less outwards, and its proper dorsal surface more or less inwards; and at the same time the preeaxial edge is turned upwards, while the post- axial edge is turned downwards. ‘This is very marked when the fin is applied to the trunk ; but the primitive disposition of the surfaces and edges of the limb becomes obvious when the fin is made to stand out at right angles to the axis of the body.

In Acipenser, as in any Teleostean fish, the rotation becomes still more marked; and divarication of the fin does not greatly diminish it, by reason of the articulation of the préeaxial fin-ray with the pec- toral arch at a point higher than the proper glenoid cavity.

When Ceratodus, or a Teleostean fish, is placed side by side with a Urodele Amphibian, such as Menobranchus, in which the fore limb naturally takes a position nearly parallel with the axis of the trunk, the manus being directed backwards, nothing is more natural than to imagine that the outer and inner aspects and the dorsal and ventral edges of the two correspond.

But a very little consideration will show that nothing can be more erroneous ; for the outer surface of the Menobranchus limb is its proper dorsal aspect, and the inner surface is its ventral aspect, as will be seen the moment the limb is placed at right angles with the trunk. In fact, though in the amphibian, as in the fish, the limb

48 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

has undergone a twist, the direction of its rotation is exactly contrary to that which has occurred in the fish. Taking the left limb in each case, the normal fin would have to be turned in the direction of move- ment of the hands of a watch to bring it to the teleostean position,

Fig. 10.

We” SCYLLIUM : The left pectoral fins of Ceratodus forsteri, Notidanus cinereus (fetal), Scyllium canicula, Chimera monstrosa, and Polyodon folium.

The preaxial (Pr.c) and postaxial (P¢.c) margins of all are turned in the same direction; #, the preaxial ray (propterygium of Gegenbaur); Mt, the metapterygium ; I, the basal or proximal joint of the axial skeleton.

while it would have to be turned in the contrary way to bring it into the amphibian position. Hence the preeaxial edge in the teleostean fin is dorsal, while in the amphibian limb it is more or less ventral ;

1876.| PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 49

and the skeletal elements on the dorsal side of the axis of the fish-fin answer to those on the ventral side of the axis inthe amphibian limb.

As Dr. Giinther has observed, the contour of the fin in Ceratodus is somewhat like that of a sickle. The preeaxial edge is convex forwards and rather thicker, especially at its proximal end, than the posterior edge, which is concave backwards in its distal and convex in its proximal half. The apex of the fin is slender and re- curved. A rounded and narrowed neck unites the limb with the trunk.

Thus the limb, as a whole, is essentially unsymmetrical when its postaxial and preeaxial halves are compared. A corresponding asym- metry is strikingly obvious in the skeleton when it is prepared by removing the integument and muscles of the dorsal face, while the undisturbed condition of the parts is preserved by leaving the ventral integument and muscles untouched (fig. 10).

it will be seen that, on the preeaxial side (Pr.a), each of the sub- quadrate segments of the median part of the skeleton, except the first and the terminal segments, gives attachment by its distal angle to a single jointed ray. The proximal or first ray (#) is much stouter than any of those which succeed it; and all take a direction approximately parallel to one another, their long axes forming an acute angle with that of the series of median segments. In the distal portion of the fin, the postaxial rays have a similar arrangement, and are only more slender than the preaxial rays. But the second seg- ment bears no fewer than five rays. Of these, the proximal, which is shortest and slenderest, stands out at right angles to the axis of the series of median segments ; while the others are gradually in- clined at a less and less angle to it. The third segment and the fourth each carry two postaxial rays; the rest have but one.

Dr. Giinther’s figures show that, in his specimen also, the fourth and the third segments each bore two postaxial rays; but there are only four attached to the second segment, and all these are represented as if they had nearly the same inclination to the axis of the fin as the preeaxial rays.

To dwell so strongly upon these minutize may seem to be making a great deal of a very small matter; but its importance becomes manifest when the fin of Ceratodus is compared with that of other fishes.

In my ‘ Preliminary Essay on the systematic arrangement of the Fishes of the Devonian epoch”’*, I made use of the term ‘Crosso- pterygian”’ to express a peculiarity which is very strikingly manifest in the fishes to which I applied it, the fin-rays of the paired fins being disposed, like a fringe, round an oval, or elongated, central space covered with scales. The Crossopterygii, however, were not defined by this character alone ; and hence the fact that truly fringed fins are found beyond the limits of that group does not interfere with its per- fectly natural character. In strictness, all fishes which possess paired fins are Crossopterygian in so far as the fin-rays always fringe the

* Memoirs of the Geological Survey of the United Kingdom, decade x. 1861, Proc. Zoot. Soc.—1876, No. 1V. 4

50 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

edges of the fin; and they differ only in the relative extent of the central area, on which the fin-rays do not encroach.

All the Chimeeroids and Plagiostomes are eminently crossoptery- gian so far as their fins are concerned; and therefore we might expect to find in the skeleton of the pectoral fins of these fishes a modification of the skeleton of that of Ceratodus. But in most of these fishes the skeleton of the fins has undergone such an amount of metamorphosis that it is difficult to reduce it to the type of Cera- todus. In Notidanus*, however, the skeleton of the pectoral fin affords the key to the nature of this metamorphosis. Here (fig. 10) there is an axial cartilage, the broad proximal end of which articulates with the pectoral arch. Distally it diminishes in diameter, and ends by a truncated face, with which another slender cylindrical cartilage, also axial in position, is articulated.

I take these two cartilages to represent the shrunken axis of the fin of Ceratodus. The preeaxial basal angle of this axial mass is occupied by a distinct cartilage. Whether this represents the proxi- mal axial cartilage of Ceratodus, or whether it is the proximal pree- axial ray, is not clear.

The preeaxial edge of the principal axial cartilage, at some little distance from this piece, presents a series of notches, with which are articulated a corresponding number of prezeaxial rays, while, as has been already stated, a single ray is articulated to the base of the terminal axial cartilage. The uppermost or proximal preeaxial ray is two-jointed and broader than the others. On the postaxia! side there is a triangular cartilage (WV), wide distally, very narrow proximally, where it is connected with the proximal end of the axial cartilages. Twelve postaxial rays are articulated with the wide distal edge of this cartilage. I conceive that this triangular postaxial cartilage is formed by the coalescence of the axial ends of the postaxial rays.

The tin-skeleton of Notidanus thus results, in the simplest: possible manuer, from the shortening of the axis of such a fin-skeleton as that of Ceratodus and the coalescence of some of its elements.

In Cestracion (fig. 11) the same process is carried a step further. Here there is a large cartilage (1) which articulates with the pectoral arch by a concave facet, and corresponds with the proximal axial car- tilage of Ceratodus and Notidanus. United by ligament with its hinder concave margin is the triangular postaxial cartilage (M2), which obviously answers to the similarly shaped postaxial cartilage of Notidanus, and which bears a series of postaxial rays, of which the first is directed almost at right angles to the axis of the fin, as in Ceratodus. The first preeaxial ray (#2) is very large and bifurcates distally. The ray which is attached to the distal angle of the axial cartilage probably answers to the ray-like termination of the axial skeleton in Notidanus ; but it is not distinguishable from the rest.

In the Dogfish (Scy/lium) (fig. 10) the further shortening of the axis gives rise to still greater changes. The axial cartilage (meso-

* The figure represents the fin of the foetal Nofidanus to which I have already

referred. The figure of the fin of an adult of the same species given by Gegen- baur (Untersuchungen, Heft ii. Taf. ix. fig. 2) shows essentially the same structure.

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 51

pterygium of Gegenbaur, I) is relatively small; but the enlarged post- axial cartilage (metapterygium, M¢) has extended upwards along the

IN

Sp

i x < MENOBRANCHUS ii? WY

The left pectoral fin of Cestracion philippi (letters as before), the left fore limbs of Ichthyosaurus, Plesiosaurus, Menobranchus, and the left manus of Gecko verUus.

J, humerus; #, radius; U, ulna; 7, radiale; 7, intermedium; wu, ulnare; ¢, cen- trale; c', c?, &, c4,c°, distal carpals; 1, 2, 3, phalanges of Menobranchus. In Gecko itis uncertain whether x represents the intermedium and the ulnare coalesced as in Menobranchus (i ~), or whether x is the intermedium and p is the ulnare, occupying the place of a pisiform bone.

postaxial face of the first, until it has not only reached the articular surface of the pectoral arch, but furnishes a large part of the articular 4*

Or

2 PROF. T. H. HUXLEY ON CERATODUS FORSTERI. [Jan. 4,

cavity. In like manner the proximal preeaxial ray (propterygium, R) has ascended along the preeaxial face of the axial cartilage, until it also is able to furnish a facet which completes the anterior part of the cup for the condyle of the pectoral arch.

In Squatina, similar modifications have occurred; but the axial car- tilage remains large, and the large preeaxial and postaxial cartilages are directed respectively forwards and backwards, in accordance with the form of the vastly expanded fin.

In Raia, yet further expansion is obtained by the separation of the axial and postaxial cartilages and the interpolation of postaxial rays between them. ‘The proximal ends of these enter into the articulation, as the great postaxial cartilage had already done.

The interpretation of the skeleton of the pectoral fin of Chimera presents some difficulties. This skeleton consists (fig. 10) of :—(1)a proximal cartilage (1), which articulates by an excavated surface with the condyle of the pectoral arch ; (2) a flat, curved, elongated middle cartilage (Mt), which is inclined backwards; (3) a small semi- lunar distal cartilage (¢c), which fits onto the convex distal end of the last. At the end of the convex posterior edge of the distal car- tilage is a small cartilaginous ray, consisting of a long basal and a short terminal segment. Similar rays, which gradually become longer, follow this along the free convex edge of the distal cartilage and that of the middle cartilage; but the proximal end of the latter bears a much stronger ray, with a wide base (#), which for the most part unites with the ventral edge of the proximal cartilage (I), but is con- nected with the middle cartilage (M¢) by its posterior produced angle.

There can, I think, be no doubt that the proximal cartilage (I) in Chimera answers to the proximal cartilage in Ceratodus. The small proximal postaxial cartilages also exactly correspond; and the large proximal przeaxial rays no less closely answer to one another. But if this be so, it follows that the whole skeleton of the fin in Ceratodus is represented in that of Chimera. The distal cartilage (c) in Chimera is the result of the coalescence of the bases of a certain number of the postaxial rays, as is obvious on tracing the series round.

Hence it would appear that all that can represent the series of median segments except the first is the middle cartilage (M7). It further seems probable that this middle cartilage in great part, if not wholly, represents the second segment of the Ceratodus limb. The postaxial edges, a 6 and 6c, correspond closely ; but the edge ef, long in Ceratodus, is reduced to nothing in Chimera ; while the edge e¢ d, occupied exclusively by the third segment in Ceratodus, is greatly elongated and bears all the praeaxial rays in Chimera.

In order to change the skeleton of the pectoral fin of Ceratodus into that of Chimera, all that will be necessary, if this comparison is correct, is that the third and following median segments of the former shall be gradually reduced, either by abortion or coalescence with the second, more and more postaxial fin-rays becoming attached

1876.] PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 53

to the postaxial edge of the second segment, and more and more of the praaxial rays to its preeaxial edge. At the same time the first preaxial ray, enlarging backwards and forwards, intercepts the proximal ends of two or three of the following rays, and comes into connexion with the proximal segment.

The difficulty which arises out of this apparently natural interpre- tation of the parts of the skeleton of the fin of Chimera consists in this—that it leads to a doubt as to the true nature of the postaxial cartilage (M¢) in Scyllium, and therefore in other Plagiostomes. For this metapterygial cartilage cannot at the same time represent coalesced postaxial rays, as the analogy of Notidanus would suggest, and the second joint of the axial skeleton, as the analogy of Chimera, on the interpretation just given, indicates. If, following the analogy of Notidanus, we consider Mt in Chimera to be formed of coalesced postaxial fin-rays, then the structure will present no difficulty, but will come very near that presented by the fin of Cestracion. The study of the development of the parts can alone solve this problem ; but I am inclined provisionally to adopt the latter hypothesis, plausible as the former seems.

Polypterus and Polyodon furnish the best connecting links between the Plagiostome fin and that of the other Ganoidei and the Teleostei. In Polypterus, the Scyllium type is essentially pre- served. In Polyodon and all other Ganoids of which the fin- structure is known, the type is essentially that of the Rays, in so far as fin-rays enter into the glenoid articulation behind the proximal median segment (1). ‘These and many other special modifications of the fish’s fin have been carefully worked out by Gegenbaur™, to whose excellent descriptions I have nothing to add.

If the interpretation which | have here endeavoured to make good is correct, it is clear that, as Gegenbaur has suggested, Ceratodus presents us with the nearest known approximation to the fundamental form of vertebrate limb, or archipterygium. But the asymmetry of the skeleton of the fin of Ceratodus, and the differences between its distal and its proximal portions, as well as the fact that the proximal median segment has no rays, appear to indicate that the veritable archipterygium has undergone a certain amount of modification even in Ceratodus. Analogy leads to the suspicion that a still more archaic fish than Ceratodus would have as many pairs of rays as median pieces. In this condition the skeleton would be made up of homologous segments, which might be termed pteromeres, each of which would consist of a mesomere with a preeaxial and a postaxial paramere. And as this is the actual state of a great porcion of the skeleton of the fin in Ceratodus, it may perhaps be permissible to carry speculation as to the primitive condition of tie vertebrate limb thus far. Dr. Giinther and Professor Gegenbaur go a step further, and suggest that even this archipterygium may be the secondary pro- duct of the coalescence of many longitudinal cartilaginous elements, which are united by their bases, while they fray out, as it were, at regular intervals towards the distal end of the limb. In this case,

* ‘Untersuchungen,’ Heft ii, ‘‘ Brustfiosse der Fische,” 1860.

54 PROF. T. H. HUXLEY ON CERATODUS FORSTER. [Jan. 4,

Gegenbaur has most ingeniously suggested that the pectoral arch, with its limb, would correspond with a branchial arch and its rays.

it will be observed that the view of the special homologies of the elements of the skeletons of the fins of fishes which I have ventured to put forth differs, fundamentally, both from that suggested by Dr. Gunther and from that advanced by Gegenbaur, either in its original form or as he has modified it subsequently to the discovery of Ceratodus.

The former says (/. ¢. p. 533):— When I designated the arrange- ment of the parts of this pectoral skeleton unique, I did not mean to convey the idea that no homological relation could be pointed out between the parts of the pectoral skeleton of Ceratodus and that of other fishes. It is quite evident that we have here a further deve- lopment of the simple pectoral axis of Lepidosiren in the direction towards the Plagiostomes. The pectoral skeleton of Lepidosiren paradoxa consists merely of the central series of cartilages of Cera- todus ; there is no fin-like expansion of the skin of the pectoral limb, which is a simple tapering filament. In Lepidosiren annectens this pectoral filament is bordered by an expansion of the skin along its lower edge ; and even minute fin-rays are imbedded in each lamina of the fold; in order to support this low, one-sided, rayed fringe, very small, single-joited cartilages are added to the axis*. The fin is still more developed in Ceratodus: it has become a broad, scythe- shaped paddle, dilated by a fold of the skin, with two layers of fin- rays surrounding it in its entire circumference ; therefore supporting cartilaginous branches are added on both sides of the axis; and most of the branches are composed of several joints, in order to reach the more distant parts which require the support.”

This is the exact converse of the view of the relations of Lepido- siren and Ceratodus which, in agreement with Gegenbaur, I am disposed to take. The fin of the former appears to me to be a reduced and metamorphosed state of the more primitive condition retained in Ceratodus.

Dr. Gunther goes on to say that “the arrangement of the limb-ske- leton of Ceratodus is foreshadowed in the pectoral fin of Acipenser.”’ On the contrary, in my judgment, the pectoral fin of Acipenser has been derived by much modification from a Ceratodus-like type.

In referring to those points in which I venture to dissent from Professor Gegeubaur’s interpretation, I cannot refrain from express- ing my sense of the very great value of his investigations into the morphology of vertebrate limbs, and my grateful indebtedness to the rich fund of new facts and new ideas which they contain. However, I found myself unable fully to accept his theory of the fish’s fin and the vertebrate limb generally, in its original form ; and { expressed my hesitation and its grounds in the German version of my ‘Manual of the Vertebrata’+. Gegenbaur’s later view is con-

* Four or five of these ray-bearers are obliquely attached to each joint of the axis (Peters, Miller’s ‘ Archiv,’ 1845, Taf. 2. fig. 2).

t ‘Handbuch der Anatomie der Wirbelthiere,’ iibersetzt von Dr. F. Ratzel (Breslau, 1873), pp. 34, 35.

1876.| PROF. T. H. HUXLEY ON CERATODUS FORSTERI. 4)

cisely stated in his ‘ Grundriss der vergleichenden Anatomie,’ 1874, p. 493, in the following words :—

‘‘The very various forms of the skeleton of the free limbs are deducible from a fundamental form of which only a few instances remain, and which, as representing the first and lowest condition of the fin-skeleton, I term the archipterygium. This is represented by a jointed cartilaginous stem, articulated with the pectoral arch and giving attachment, on each side, to a series of likewise jointed pieces, the radiz. The whole structure, resembling a pinnate leaf, is singularly like the supporting apparatus of many Selachian gills, and thus throws a gleam of light upon the phylogeny of the limbs.

“ Ceratodus presents this form of fin-skeleton, which was perhaps usual among the Crossopterygide, at present represented only by Polypterus. The biserial rays of the fin undergo different modifica- tions. Among the Dipnoi the medial [ postaxial] rays are retained in the form of thin rods of cartilage ; while in the Selachians the lateral [ preeaxial] rays attain a considerable development and consti- tute the greater part of the massive fin-skeleton. Of the medial [postaxial] rays but few remain, though they are sufficiently distinct to sanction the assumption of a former unos extensive biserial arrangement of rays on the stem of the fin.’

The metapterygium Gegenbaur considers to answer to the axial skeleton of the archipterygium. The propterygium is formed by the union of the proximal preeaxial fin-rays. The mesopterygium is formed by a certain number of the succeeding przeaxial fin-rays.

The only part of this interpretation with which I can agree is the determination of what Gegenbaur names the propterygium as the representative of the proximal preeaxial fi-ray or rays In most cases, but not in Chimera, and probably not in Notidanus.

In my judgment, the mesopterygium of Gegenbaur is the proximal piece of the axial skeleton, which constantly retains its primary articulation with the pectoral arch. His propterygium represents the proximal preeaxial fin-ray, and his metapterygium the proximal postaxial fin-ray in almost all cases ; and the ichthyopterygium, as the typical fish-fin may be termed, differs from the archipterygium not by the more or less complete suppression of the postaxial rays, but by the general abbreviation of the whole skeleton and the gradual connexion of more or fewer fin-rays (parameres) with the pectoral arch.

In the effectual discharge of the function of the fish’s fin, increase of breadth is needed ; and this increase of surface is obtained by the cradual approximation of more and more lateral elements of the archipterygium to the shoulder-girdle.

Professor Gegenbaur has extended his theory of the limbs to the higher Vertebrata. He conceives that the axis of the archipterygium (which he considers to be the homologue of the metapterygium of the Selachian) is represented by the series of bones which is formed by the humerus, the radius, the radial segments of the carpus, and the radial digit or pollex ; while the ulna, the radial segments of the carpus and the ulnar digit, the other carpal bones, and the fourth,

56 PROF. T. H. HUXLEY ON CERATODUS FORSTERI, [Jan. 4,

third, and second digits represent so many preeaxial rays. The very serious objection that this hypothesis makes the radius and the radial digit postaxial, while, as a matter of fact, in every vertebrate animal it is preeaxial, is met by the assumption of a torsion of the humerus. But I must confess that I am wholly unable to satisfy myself of the existence of any torsion of the humerus capable of bringing about the effect attributed to it in any vertebrated animal; and, moreover, if such torsion has brought about the observed position of the manus and pes in the higher Vertebrata, any reversal of that torsion would destroy the homology of the pollex and the hallux—which is surely out of reach of doubt.

I am disposed to think, though I am far from imagining that the hypothesis can at present be demonstrated, that the higher vertebrate limb has arisen from the archipterygium in another and simpler method.

According to Gegenbaur’s view, the higher vertebrate limb is the result of further progress, in the same direction, of the meta- morphosis which has given rise to the ichthyopterygium. But this appears to me to be highly improbable. The ichthyopterygium is specialized part passu with the other peculiarities of piscine structure, and is not developed in the Dipnoi, which are the nearest allies of the Amphibia. Moreover the higher vertebrate limb, which may be termed the chiropterygium, as an organ of support and prehension, requires length, strength, and mobility of its segments—conditions exactly the opposite of those which give the ichthyopterygium its special utility.

Hence, as the most highly specialized forms of ichthyopterygium result from the shortening of the skeleton of the fin, the approxi- mation of its distal elements to the shoulder-girdle, and the multipli- tion of its rays, we might expect that the chiropterygium would take its origin by the lengthening of the axial skeleton, accompanied by a removal of its distal elements further away from the shoulder- girdle, and by a diminution in the number of the rays.

The parts which are traversed by a line drawn through the humerus, the intermedium, the centrale, the third distal carpal, and the third digit in the cheiropterygium may be regarded as so many mesomeres, representing the axis of the archipterygium. ‘lwo pairs of parameres are retained on each side. ‘The preeaxial are :—(1) the radius, the radiale, the first distal carpal, and the pollex; (2) the second distal carpal and the index. The postaxial parameres are :— (1) the ulna, the ulnare, the fifth distal carpal, and the digitus mini- mus; (2) the fourth carpal and the annularis.

In fig. 11 the skeleton of the pectoral fin of Cestracion is repre- sented side by side with the skeleton of the fore limbs of dZeno- branchus, Iehthyosaurus, Plesiosaurus, and Gecko; and the shading of the different parts of the ichthyopterygium is repeated in what I suppose to be the homologous elements of the chiropterygium. In the case of Menobranchus, however, it is possible that the true pollex is suppressed, and that the actual radial digit represents the second of the pentadactyle limb, and therefore should have been left unshaded,

1876. | AND ON THE CLASSIFICATION OF FISHES. by

In accordance with the view thus suggested, the humerus in the chiropterygium 1 is the homologue of the proximal mesomere or joint of the axis of the archipterygium, while the radius and the ulna are the homologues of the proximal ends of przeaxial and postaxial para- meres of the archipterygium.

The confirmation or refutation of this hypothesis is to be sought in development, and in the condition of the limbs in those Palze- ozoic Amphibia which may have more nearly approximated to Dipnoi than any existing or extinct forms at present known. I suggest it mainly in the hope of stimulating investigation in both these direc- tions.

IV. Taxonomy of Ceratodus, and Remarks on the Classification of Fishes.

The indications afforded by the brain, the skull, and the limbs of Ceratodus are sufficient to show that it occupies a curiously central position among the Ichthyopsida, being allied on one side to the Amphibia, on nother to the Chimeeroidei and Plagiostomi, and on yet another to the Ganoidei—especially to that. group of the Ganoids which I have termed Crossopterygida@, and to the affinities of which with Lepidosiren I called attention in 1861.

But even Dipterus, which approaches Ceratodus and Lepidosiren so closely in its dentition and in the form of its fins, is far more similar to Polypterus and Amia in other respects ; and there is, at present, no reason to believe that any of the Crossopterygian Ganoids possessed

other than a hyostylic skull, or differed from Polypterus in those respects in which Polypterus differs from the existing Dipnoi. All known Crossopterygians have jugular plates, of which there is no trace in the Dipnoi. And as to the position of the anterior nares, which appear to have been situated on the under face of the broad snout, not only in Dipterus, but in Osteolepis and Diplopterus, I have shown above that, so far from being a diagnostic character of the Dipnoi, it is simply an embryonic feature retained in them, the Se- lachians, and very probably in many of the early Ganoidei. On the other hand, in Ama, there is an even closer approximation between the Ganoids and the Teleosteans than can at present be shown to exist between any Ganoids and the Dipnoi; while the differences between the Dipnoi and the Chimeeroidei, and between the Chimee- roidei and the Plagiostomi respectively, are not less than those between the Ganoids and the Dipnoi.

It seems to me, therefore, that by forming the Dipnoi, Ganoidei, Chimeeroidei, and Plagiostomi into a group of ** Paleeichthyes,”’ from which the ‘leleostei are exclnded, as Dr. Giinther proposes to do, the differences between the Teleostei and the other hyostylic fishes are brought into undue prominence, and that it is better to retain the Miillerian groups of Dipnoi (Sirenoidei, Miller), Ganoidei, Teleostei, Plagiostom, and Chimeeroidei (Holocephali, Miller) as equivalent and distinct natural assemblages.

In discussing any system of classification, however, it must be

58 PROF. T. H. HUXLEY ON CERATODUS FORSTERI, (Jan. 4,

recollected that known forms certainly represent but a portion, and probably a small portion, of those which have existed, and that the most natural groups are therefore, to a great extent, the result of the influence of extraneous, and what may be properly termed accidental, conditions.

It has occurred to me.that, in the present state of science, it is very desirable to have some mode of stating the facts of morphology in a condensed and comprehensible form, which shall be purely ob- jective and free from speculation ; and I now proceed to illustrate my meaning by drawing up a scheme of the morphology of the Ichthyopsida.

Looking at the animals included under this head as a whole, or at the development of any of the higher members of the group, it is observable that they present a certain series of stages of differentia- tion marked by the broad characters of the skull, the nature of the olfactory and respiratory organs, and the development or non-develop- ment of an opercular fold of the integument.

Thus the skull either retains its primitive segmentation (Hntomo- crania), or the primitive segmentation is lost, and a chondrocranium is developed (Holocrania). There are two externai nostrils (Am- phirhina) or only one (Monorhina).

A pneumatocele, or air sac, which may become either an air- bladder or a lung, is developed (Pneumatoceela), or not (Apneumato- cela) ; and a fold of the integument may cover the branchial aper- tures (Operculata), or not (Inoperculata).

The Ichthyopsida also exhibit a series of stages of differentiation of the limbs, being either apodal or pedate; and, when pedate, having the limb-skeleton constructed upon the type of the archipterygium, or on that of the icthyopterygium, or on that of the chiropterygium.

Moreover, when the limb is an ichthyopterygium, it may possess one, or at most two basal elements, which articulate with the pectoral arch (unibasal), or there may be three (tribasal), or there may be many (multibasal), in accordance with the greater and greater diver- gence of the fin from the archipterygial type.

The chondrocranium may be constructed upon either the amphi- stylic, the hyostylic, or the autostylic plan.

Now, if the stages of general differentiation be indicated by points on a vertical line from which horizontal lines are drawn, and the stages of subordinate differentiation of the skull and limbs be indi- cated by points on a horizontal line from which vertical lines are drawn, we shall have vertical series of intersections indicating general differentiation, and horizontal series of intersections indicating special differentiation. Every known form will occupy some given inter- sections, and the unoccupied intersections will indicate unfulfilled, or unknown, possibilities of organization.

The following Table exhibits the groups of the Ichthyopsida arranged according to this scheme.

AND ON THE CLASSIFICATION OF FISHES,

1876.]

I. HOLOCRANIA. Autostylica. Amphistylica. Hyostylica. A. Amphirhina. SRE) eh a eee DE PAROS NCEA ROIS RATER ERY DIP 4. ee eS ae a a. Pneumatocela. Most :TELEosr EI. 1. -operculata. AMPHIBIA Dipnoi.

(caducibranchiate). °

2. inoperculata. AMPHIBIA

(perennibranchiate).:

b. Apneumatoceela. 1, operculata. 2. inoperculata.

B. Monorhina. 1. operculata.

2. inoperculata, Marsiro- BRANCHIL. Il. ENTOMOCRANIA. 1. operculata. PuARYNGO- BRANCHIL 2. inoperculata. Chiropterygium. “——————_+-- —-———_—’ — |

Polypterus. GANOWEL:

CHIMAROIDEI.

Most

Cestracion. Notidanus.

Tribasal, Multibasal. ~ : —~— | aavenenieas | Archipterygium. Tethyopterygium.

Unibasal. |

Apoda.

eH

Pedata.

60 MR. A. H. GARROD ON THE GROUND-HORNBILL. [Jan. 18,

January 18, 1576. Robert Hudson, Esq., F.R.S., V.P., in the Chair.

The following papers were read :-—

1. On a Peculiarity in the Carotid Arteries, and other Points in the Anatomy, of the Ground-Hornhbill (Bucorvus abyssinicus). By A. H. Garrop, M.A., F.Z.S., Prosector to the Society.

[Received December 10, 1875. ]

A specimen of Bucorvus abyssinicus having recently died in the Society’s Gardens, I have had the opportunity of examining the anatomy of that genus for the first time. In all respects, except the one to be referred to as regards its arterial system and a minor myo- logical feature, it agrees an Buceros. As is the case in all the Bucerotidee, there was not a trace of fat to be found on any part of the body of the adult bird, though it may be present in young individuals; and the air-cells extended so extensively among the muscles that on removing the skin no dissection was required to display each muscle from origin to insertion. The muscular tissue was also strikingly compact and dry, as in the Hares among mam- mals, in which animals also it is known that fat is never deposited. The oil-gland, as in Buceros, instead of being simply tufted, was also covered with a dense mat of short feathers, about a square inch im area.

In Buceros, as in most birds, the two carotid arteries, immediately they separate from their respective innominate arteries, converge, and meet before they have gone any considerable distance up the neck, to run together in the median hypapophysial canal on the anterior surface of the cervical vertebree. In some Parrots the left carotid, instead of coursing the above-mentioned canal witb its fellow, runs up along the side of the neck together with the left pneumogastric nerve to reach the head. In Bucorvus, in the specimen dissected by me at least *, a further extension of this peculiarity ob- tains ; for both the carotids, instead of meeting and running toge- ther, course up the sides of the neck in company with the pneumo- gastric nerves and jugular veins of their respective sides, as they do in mammals, aud in no other birds, as far as [am aware. Auother peculiarity is, that these abnormally placed carotids are particularly small in calibre ; and I noticed that the vertebrals were as conspicu- ously large, evidently to make up the blood-supply of the head.

As to the visceral anatomy, it may be mentioned that the uni- formly cylindrical crop leads, through the zonary proventriculus, to the stomach, which is much like that of Bucerost, but more mus- cular, and with the dense epithelial lining much more firmly _* A second specimen, since received, entirely agrees with the above descrip- tion.

t Vide Trans, Z. S. vol. i. pl. xviii. p. 122.

CuyItn ayporcry 7 STAT Sa SHHTTO YHCHO HHI JO SHITINVA AO LYVH!

amit yeyUeH Nx

—————— + —_ -.

“TAA WN HD dea ST TD

, Lippy s s AA f fy WYipy iY yi. Yj UM MEHMED) Yi

2p sali

a Ge WILDL SUNTTA TY

Wij Wj — pw Wf ae

bh hiolilth why

?

pee Ui DP PLA OLA Yj Vf TW Y/ U UW)

YY

(OP IhULs. DY

Y ~ UMMM

Yy

z Ops, /)

SSAA

DG TPAC EC C8 TG Fes ETUC CTE

Sal SOTA

| Yf Bp TF

1876. ] MR. KE. R. ALSTON ON THE ORDER GLIRES. 61

attached. The intestines are particularly capacious, being quite an inch in diameter ; they are four feet in length, and have no colic czeca connected with them. The liver has a gall-bladder ; and the left of the two lobes which go to form it is a little the smaller. In the syrinx there is a pair of intrinsic muscles to the first bronchial half- ring. The tongue is almost as small as it is in the Pelicans.

Myologically, of the five museles in the thigh, which, in my esti- mation, are specially significant*, the ambiens is absent, as are the femoro-caudal and the accessory femoro-caudal, the semitendinosus and the accessory semitendinosus being well represented. In this respect Bucorvus, therefore, differs from Buceros and Toccus, the accessory femoro-caudal muscle being present in the two latter genera. As is most probably known to many, Bucorvus walks, placing one foot in front of the other, whilst Buceros always hops, with both feet together.

2. On the Classification of the Order Glires. By Epwarp R. Atston, F.G.S., F.Z.S.

[Received December 14, 1875.] (Plate IV.)

The following attempt at a natural arrangement of the gnawing mammals is the result of a revision of the genera of that order, undertaken at the suggestion of Professor Flower, on which I have been for some time engaged.

In laying it before the Society it may be well to say at once that the proposed classification has few claims to novelty, being in fact a modification of that first suggested by Mr. Waterhouse, and since improved by Professors Gervais, Brandt, and Lilljeborg. Neverthe- less I have found it necessary to propose several changes in the arrangement of the families and subfamilies, as well as rectifications in their nomenclature. I have also taken the fossil forms into consi- deration, and have thereby been compelled to propose the establish- ment ef a new suborder. Lastly, I have endeavoured to bring the whole up toa level with the improved state of our knowledge, which has gained much of late years from the labours of Milne-Edwards, Gray, Giinther, Leidy, Coues, and others, but, above all, from those of Dr. Peters.

The order Glires has always been a stumbling-block to naturalists, owing to the immense number and variety of the forms which it includes, and to their puzzling cross-relationships to one another. Nor has paleontology here yielded, save ina few instances, the same help which she has lent the student of some other orders of mam- mals; for most of the fossil rodents yet discovered are referable to families which still exist, and are often closely allied to recent

genera. * P. Z. 8. 1873, p. 626, and 1874, p. 111.

62 MR. E.R. ALSTON ON THE ORDER GLIRES. [Jan. 18,

These difficulties were insuperable as long as Zoologists placed their trust in outward appearances; and when sounder principles gained ground it was some time before the necessary anatomical data could he collected. Without detailing all the classifications which have been proposed within the last fifty years, I must briefly men- tion the memoirs of the four zoologists on whose labours, as already stated, the following proposed arrangement is chiefly based.

In 1839, Mr. G. R. Waterhouse, then Curator of this Society, published the first of a series of essays in which he may confidently be said to have laid down the groundwork of a natural arrangement of this order*. Unfortunately, as the mammalogist must think, this accurate and thoughtful zoologist has long since turned his attention to other departments, and only a small portion of his great work on the Rodentia ever appeared}. In his first papers Mr. Waterhouse, taking the characters of the skull and mandible as his chief guides, arranged the Rodents into three great families, the Murina, Hystricina, and Leporina, with twelve subfamilies. Con- tinuing his labours for ten years, his views were naturally changed on many points. Latterly he separated the Sciuride as a group equal in value to the other two, the following being the arrangement of families and subfamilies adopted in his later writings :—

RODENTIA.

I. Sciuride. {Il. Hystricide.

Il. Muride. 1. Hystricina. 1. Saccomyina. 2. Dasyproctina. 2. Dipodina. 3. Echimyina. 3. Ctenodactylina. 4. Octodontina. 4. -Murina. 5. Chinchillina. 5. Spalacina. 6. Caviina. 6. Arvicolina. IV. Leporide. 7. Bathyergina.

In 1848 Professor Gervais published an arrangement of this order, in which he instituted two principal sections or suborderst. The first of these included the ordinary Rodents with only one pair of incisors above and below; the second consisted of those with two pairs in the upper jaw, and was consequently equivalent to Llliger’s group Duplicidenta§. The following was Professor Gervais’s ar- rangement of the families :—

* «Observations on the Rodentia,” Mag. Nat. Hist. iii. pp. 90-96, 184-188, 274-279, 593-600; Ann. Nat. Hist. viii. pp. 81-84, x. pp. 197-203 (1889-42). “ On the Geographical Distribution of the Rodentia,” P. Z.S. 1839, pp. 172-174. “Order Rodentia,” Keith Johnston’s Physical Atlas, Phytology and Zoology, map. 5, letterpress (1849).

+ Natural History of the Mammalia, vol. ii. “‘ Rodentia.” London 1848 (in- cludes only the families Leporide and Hystricide@).

t Dict. Univ. d’Hist. Nat. xi. p. 202 (1848); Ann. Scien. Nat. 3™¢ sér. t. xx. pp. 245, 246 (1853).

§ Prod. Syst. Mamm. p. 91 (1811).

1876. ] MR. E. R. ALSTON ON THE ORDER GLIRES, 63

GLIRES. I. Rongeurs ordinaires. 6. Lagostomide. 1. Sciuridee. 7. Hystricide. 2. Pseudostomidee *. 8. Caviadee. 3. Muridee. 4. Dipodide. Il. Rongeurs duplicidentés. 5. Ctenomydee. 9. Leporidee.

In 1855 appeared Professor J. F. Brandt’s learned and elaborate review of the cranial structure and classification of recent Rodents’. On the whole he adopted Mr. Waterhouse’s arrangement; but recog- nizing the fact that his four groups were of more than family value, he raised them to the rank of suborders. He also made several changes in the arrangement of the families and the position of some of the raore doubtful forms, and imposed new names on all the divisions, which he arranged in the following order :—

GLIRES. 1 ee Ill. Hystricomorphi. Sciuroides. 8. Hystricoides. 16 Mipnoean 9. Spalacopodoidess. 2. Myoxoides. 10. Eriomyoides'|). 3. Castoroides. 11. Hemionychoides4. 4. Sciurospalacoides*. IV. Lagomorphi. 5. Myoides. 12. Lagordes. 6. Spalacoides. 7. Dipodoides.

Eleven years later Professor Lilljeborg published his admirable sys- tematic review of this order**. Appreciating the great importance of the characters which separate the Leporide and Lagomyide from all other rodents, he adopted Gervais’s two suborders under the names Glires Simplicidentati and Glhres Duplicidentati. In the arrangement of the former he pointed out a well-marked and con- stant character which separates the Myomorphi of Brandt from both the Scturomorphi and the Hystricomorphi, namely the complete ankylosis in the former of the lower part of the tibia and fibula. Altbough Professor Lilljeborg does not retain these divisions in his tabular arrangements, he observes that the M/yomorphi include the

* Saccomyina, Waterhouse. t+ J. F. Brandt, ‘“‘ Untersuchungen iiber die craniologischen Entwicklungs-

stufen . . . und Classification der Nager der Jetzwelt,” Mém. de l’Acad. Imp. de St. Pétersbourg, 6™* série (Sciences Naturelles), vii. pp. 127-336, 12 pls. (1855).

{ Containing Geomys and Thomomys.

§ Equal to Echimyina and Octodontina of Waterhouse.

|| Chinchillina, Waterh.

{ Equal to Dasyproctina and Caviina, Waterh.

** Systematisk (Uifversigt af de Gnagande Daggdjuren, Glires. 4to. Upsala, 1866

64 MR. E. R. ALSTON ON THE ORDER GLIRES. | Jan. 18,

first siz, the Seiuromorphi the seventh, and the Hystricomorpht the cighth to eleventh families in the following Table :—

GLIRES. I. Simplicidentati. 8. Haploodontidee. 1. Muride. 9. Chinchillidee. 2. Spalacidee. 10. Spalacopodidee. 3. Dipodidee. 11. Hystricidee. 4. Myoxidee. Il. Duplicidentati. 5. Saccomyide. 12. Lagomyide. 6. Castoridee. 13. Leporidee. 7. Sciuridee.

In his recent work on Scandinavian mammnals*, Professor Lillje- borg retains the above arrangement, adding a new family, allied to the Muride, for the reception of Milne-Edwards’s genus Lophiomys.

As it became clear that the cranial characters of the groups pro- posed by Waterhouse and Brandt are liable to exceptions, and that they are connected by more or less intermediate forms, they have not been regarded with favour by recent systematic writers; never- theless the affinities which they indicate have been very generally accepted in the arrangement of the families. But if a group is a natural one, it should not, I think, be rejected because it is difficult to characterize. The Insectivora may be taken as an example of a very natural order, of which, in Professor Huxley’s words, ‘it is exceedingly difficult to give an absolute definition.” Even if it were not possible to separate the first three of Waterhouse’s great families by perfectly constant characters, they ought, as it appears to me, to be recognized as indicating three distinct lines of develop- ment. But by the help of the characters of the leg-bones, pointed out by Professor Lilljeborg, the difficulty is overcome. In the few cases in which the cranial differences fail us in separating the sciurine rodents from the murine, and the latter from the hystricine, the complete ankylosis of the lower part of the tibia and fibula in the second group comes to our aid. As far as I am aware, there is no real exception to this rule; for the union between these bones sometimes observed in the genus Pteromys, in aged individuals of Castor, and in several of the hystricine series, is totally different from the true fusion which we meet with in all the known Myomor- phi. The first and third groups, which agree with one another in this point, are at once separated from each other by the form of the mandible, as well as by the whole type of cranial structure.

But while recognizing these groups as true and natural, I cannot consider them to have any thing like the rank of Brandt’s Lagomor- phi, and rather treat them as sections of Lilljeborg’s suborder Glires Simplicidentati, of somewhat similar value to the sections instituted by Turner and Flower in the Carnivora fissipedia.

Before proceeding to some general remarks on these various divi- sions, it should be premised that an absolutely equal value is not

* Sweriges och Norges Ryggradsdjur, I. Daiggdjuren. Upsala, 1874.

1876. ] MR. E. R. ALSTON ON THE ORDER GLIRES. 65

here claimed for all the families and subfamilies. Such is the variety of the extent of differentiation that it appears to me that no Procrus- tean standard can be applied. LKither we must load our memories with tribes, legions, cohorts, series, superfam:les, &c., or we must be content with divisions pretending only to an approximate equality of value.

General Remarks.

The first suborder of Rodents, GLiIrES SIMPLICIDENTATI, con- tains an enormous majority of both the recent and extinct forms, and is at once proved by its dentition to be the most highly specialized division of the order. There is only one pair of incisors above and below at all ages ; and their enamel is restricted to their front surface. In the skull, the incisive foramina are moderate and separate, the optic foramina are very rarely confluent, and there is an alisphenoid canal*. ‘The fibula is either ankylosed below to the tibia or free, and does not articulate with the caleanium. Vesicular glands are present ; and the testes are usually abdominal, only temporarily de- scending into the scrotal pouches’.

Of this suborder the first section, Seiwromorpha, has for con- stant characters the combination of a peculiar form of mandible with

Mandible of Arctomys marmotta.

the persistence of the fibula as a distinct bone throughout life. The former character at once separates it from the Hystricomorpha, the latter from the Myomorpha. In the mandible the angular portion springs from the lower edge of the bony covering of the inferior incisor, not from its outer side ; and its outline is more or less rounded.

* Cf Turner, P. Z. 8. 1848, p. 65. + Cf. Owen, Anat. of Vert. iii. p. 649. Proc. Zoou. Soc.—1876, No. V. 5

66 MR. E. R. ALSTON ON THE ORDER GLIRES. [Jan. 18,

The difference between the mandible characteristic of the Sciuro- morpha and Myomorpha and that peculiar to the Hystricomorpha will be best shown by a comparison of the figures*. In the more typical forms the infraorbital opening is not enlarged to give passage to a portion of the masseter muscle ; and in all the malar extends far forward, and is not supported below by a continuation backwards of the maxillary zygomatic process. The incisive foramina are small, and confined to the intermaxillaries ; the foramina of the base of the skull are proportionally small ; and there 3s no interpterygoid canalt. The clavicles are always perfect, the posterior ridge of the scapula is strongly developed, and the acromion is broad and flattened. Externally the muffle is naked, the upper lip usually cleft, the nostrils rounded above and comma-shaped, the ears hairy, and the tail cylindrical and well haired, except in Castor, in which it is flattened and scaly.

The typical family, the Sciuride, easily distinguished by their postorbital frontal processes, has been divided for convenience into two subfamilies, the long-tailed arboreal Squirrels (Seiurine), and the short-tailed terrestrial Marmots (Arcfomyine), though it must be confessed that their differences are merely adaptive and not very striking. The other families are all more or less aberrant, and their true affinities bave been the subject of much discussion.

The first of these is the dnomalurtde ; and I have alreadyt given my reasons for considering that it must be regarded as an undoubted though specially differentiated family of this section. The sciurine affinities of the Haplodountide, in spite of its peculiar dental and cranial characters, have been definitely established by Dr. Peters§, although Prof. Lilljeborg has strangely relegated it to the Hys- tricomorpha\. The position of the remaining family, Castoride, has been a still more vexed question, ever since the Beaver has been extricated from the old jumble with the Musquash and the Coypu. Professor Gervais appears to have been the first to treat Castor as an aberrant member of the present group [, in which Mr. Water house** and Professor Bairdt++ have concurred ; and aithough these writers have not been generally followed, it seems evident to me that we must revert to their views. Professor Brandt fully recognized that in all the more important points the osteology of Castor agrees with that of the Sciuromorpha, but considers this resemblance to be negatived by the external habitus and manner of life, as well as by the structure of the teeth, feet, and tailtt{. Prof. Lilljeborg places the

* By permission of Professor Flower the illustrations have been drawn from specimens in the Museum of the Royal College of Surgecuns.

+ This name was proposed by Mr. Waterhouse for the fissure which in some rodents leads from the bottom of the pterygoid fossa into the orbit. Cf Turner, P. ZS. 1848, p. 63.

t “On Anomalurus, its Structure and Position,” P. Z. 8. 1875, pp. 88-97.

§ Monatsb. Ak. Berlin, 1864, p. 177. || Op. et. p: 9.

“{ Dict. Univ. d’Hist. Nat. xi. p. 203.

** Physical Atlas, Zool. map, 5 (letter-press).

++ North-American Mammals, p. 3800.

tt Op. ez¢. pp. 149, 150.

1376. ] MR. E. R. ALSTON ON THE ORDER GLIRES. 67

Castoride among the Myomorpha, but on the boundary between them and the Seivromorpha, remarking that the fibula is stout, and remains long separate from the tibia*. But the characters of these bones seem to me to be strictly sciurine ; for though they are more or less firmly attached to one another in aged individuals, yet they always appear to remain essentially distinct throughout their length. Less weight is now generally given to external characters than was the case when Prof. Brandt wrote ; and the purely adaptive differentiation of the teeth, feet, and tail cannot be allowed to outweigh the nume- rous and important characters which are at once evident on a careful comparison of the skulls and skeletons of a Beaver and a Marmot. These external peculiarities, coupled with these of the digestive, excretory, and generative organs, certainly show that the Castoride is a very isolated and aberrant family; but they do not appear to indicate any specially murine affinities.

Mandible of Cricetomys gambianus.

An interesting confirmation of these views as to the position of the Beaver is afforded by the fossil rodent of the American Miocene, to which Professor Leidy has given the name of Ischyromys, In this form the dentition of the typical Sciurid@ is combined with a form of skull which very closely resembles that of the Castorida, and especially that of the Miocene genus Stenofiber. It differs from both these groups, however, in the possession of a large infra- orbital opening, and should form, as it appears to me, a fifth family of the Sciuromorpha, under the name of Lschyromyidey.

The second section, Myomorpha, is at ounce separated from either of the others by the single character of the complete fusion in the adult of the lower part of the tibia and fibula. Externally, the muffle and upper lip are as in the last section ; and the tail is cylin-

* Op. cit. pp. 7, 39.

+ Gf, Leidy, Journ. Acad. Philadelphia, 2nd ser. vol. vii. pp. 835-338, pl. xxvi. ; Cope, Report U.S. Geol. Survey, 1873, p. 477.

-

a*

68 MR. E. R. ALSTON UN THE ORDER GLIRES. [Jan. 18,

drical, either covered with scales arranged in rings, or more or less hairy. The Myomorpha contains such a variety of forms, many of them much specialized, that it is only by allowing for exceptions that its definition can be carried further ; still many and important distinctions are common to the vast majority. The form of the man- dible, by which the section was first separated from the Hystrico- morpha, agrees with the last section, the angular portion springing from the lower edge of the bony covering of the lower incisor, excepting in the subfamily Bathyergine, in which it has exactly the form so characteristic of the hystricine rodents. The other cranial characters are very varied. In the more typical forms the infra- orbital opening has a peculiar shape, which may be termed murine ; it is high, perpendicular, narrow, wider above than below; and the lower root of the maxillary zygomatic process is perpendicular and flattened into a thin plate with a rounded anterior edge. The zygoma is comparatively slender; the malar seldom advances far forward (except in the Dipodide), and is usually supported below by a con- tinuation backwards of the maxillary process, being reduced in some

Mandible of Bathyergus maritimus.

of the typical genera to a mere splint between the latter and the squamosal process. The outer walls of the pterygoid fosse are gene- rally obsolete ; and they have no direct fissure at the bottom, except in the aberrant subfamily named above. The clavicles are perfect except in the Lophiomyide. ;

1876. ] MR. E. R. ALSTON ON THE ORDER GLIRES. 69

Of the seven well-marked families into which this section may be divided, the typical one, the Muride, comprises a great number of genera. The best classification of these with which I am acquainted is that of Dr. Peters, which is here adopted with some little modifi- cation, his groups being ranked as subfamilies, and a slight alteration being made in their arrangement*. M. A. Milne-Edwards having clearly proved that the genera Hilobius and Siphneus really belong to this familyt, the subfamily Siphneine is now placed alongside of the Arvicoline, with which it is so nearly allied.

Of the other families, the Myoxide bear a very strong outward resemblance to the Sciuromorpha, which, however, is not mark- edly confirmed by their anatomy. Dr. Peters having shown that Platacanthomys must be removed to the JZuridet, the remaining genera of Dormice are all very closely allied, and are isolated from all other known rodents by the complete absence of the cecum. The “next family, Lophiomyide, contains a single form differing in struc- ture not only from all the rest of the order, but even from all the known members of the mammalian class§. Nevertheless, if the ex- traordinary development of the temporal and malar regions be over- looked, the whole skull of Zophiomys is truly murine in type; and this is confirmed by all the other more important points in its anatomy. It is strange that, although its habits appear to be at least partly arboreal, Lophiomys should differ from all the rest of the section in the incomplete development of its clavicles.

The Spalacide, even when disencumbered by the removal of Siphneus and Ellobius, are still divisible into two subfamilies—the typical Spalacine, which have the normal mandible of the section, and the Bathyergine, in which are found the hystricine characters already mentioned (supra p.68), and which were hence named Spa- laces subhystriciformes by Prof. Brandt. The next family, which in- cludes the American rodents with cheek-pouches which open outside the mouth, was founded by Mr. Waterhouse under the name of Sacco- myide, and subsequently divided by Prof. Baird into two subfamilies, Geomyine and Saccomyine. Dr. E. Coues, in a recent valuable memoir, has contended that these latter divisions should rank as separate though allied families||—a view in which I cannot agree. The diversity in their outward form may be paralleled by that in the Squirrels and Marmots ; and the differences in their cranial structure are, as Dr. Coues himself observes, of a superficial nature. In any case, Mr. Waterhouse’s name must be changed; for Dr. Peters has shown] that the genus Saccomys of Frederic Cuvier is in all proba- bility, a synonym of Desmarest’s Heteromys. The oldest and best-

* The names only of these divisions appeared in the Monatsb. Ak. Berlin, 1866, pp. 18, 14.; for access to Dr. Peters’s hitherto unpublished characters I am indebted to the courtesy of the author.

t Recherches pour servir 4’ Hist. Nat. des Mammiféres, pp. 71-129.

t P. Z. 8. 1865, pp. 397-399.

§ Cf. A. Milne-Edwards, Nouy. Arch. du Mus. iii. pp. 81-118.

|| Rep. Explor. Colorado River, p. 215; Bull. U.S. Survey of Territories, 2nd ser. no. 2, pp. 81-90.

70 MR. E. R. ALSTON ON THE ORDER GLIRES. [Jan. 18,

known genus will therefore legitimately give name to the family Geomyide, the subfamilies standing as Geomyine and Heteromyine.

Here I am inclined to place, at least provisionally, a family of Rodents which flourished in Europe in the later Eocene and Miocene periods, and of which three genera are known. Each of these was at first ascribed to a distinct family of the Hystricomorpha—namely, Theridomys to the Octodontide, Archeomys to the Chinchillide, and Isstodoromys to the Caviide. M. Gervais was the first to re- move them entirely from that section, uniting the first two in his tribe Théridomins of the family Myowidés (which also included Anomalurus). He placed Issiodoromys in his tribu des Pédétins of the Dipodide, but with the remark that it might have to be rele- gated to the Théridomins*. That these animals were strictly myo- morphine is clearly shown by the form of their mandibles. Now that dnomalurus has been definitely separated from the Myovide, there seems to be nothing to unite these ancient rodents with that

Fig. 4.

Mandible of Capromys pilorides.

family ; and, both in their very varied dentition and in what we know

of their cranial characters, they appear to me to be very nearly related

to the Dipodide—the two former to the true Dipodine, and the last

to the Pedetine. Meantime it may be best to allow them to stand as a distinct family under the name of Theridomyide.

The last family of the Myomorpha, the Dipodide, is divisible

into three plainly marked subfamilies—Jaculine, Dipodina, and * Zool. et Paléont. Franc. (2me ed.), pp. 31-36.

1876. ] MR. E.R. ALSTON ON THE ORDER GLIRES. 71

Pedeting, of which the first is the most murine, and the second the most highly specialized, while the third shows more than superficial resemblances to the Chinchillide.

The third section, Hystricomorpha, is characterized by the form of the mandible, combined with persistence of the fibula as a distinct bone throughout life. In the mandible the ascending ramus and coronoid process are low, and the angular portion does not spring from the lower edge of the bony covering of the lower incisor. In the great majority of forms in which that tooth is long, the angular portion springs from the outer side of its bony sheath, so that when viewed from below there is a longitudinal groove between the angu- lar and dental portions. In the Caviide, in which the incisors are short, ‘the direction of the incisor is such that, were it prolonged

Mandible of Cavia aperea.

backwards, the alveolus of the tooth and the angular portion of the jaw would hold the same relative positions” as in the other members of the section*. This difference in the form of jaw will be best under- stood by a comparison of figures 4and 5. In the skull the infraorbital opening is always large, oval or subtriangular, an interpterygoid fissure is present, and the foramina of the base of the skull are pro- portionally large, while the incisive foramina are small. The fron- tals have no distinct postorbital processes (except in Chetomys) ; and the malar, which is rarely continued far forward, is not sup- ported below by a continuation of the maxillary zygomatic process. The clavicles are either perfect or imperfect ; and one premolar is present above and below (except in Ctenodactylus). The upper lip is rarely cleft, the muffle is usually clad with very fine hairs, and the

* Waterhouse, Nat. Hist. Mamm. ii. p, 149.

72 MR. E. RE ALSTON ON THE ORDER GLIRES. — [Jan. 18,

nostrils pointed above, sigmoid or linear. The ears are very generally emarginate behind ; and the tail, when present, is cylindrical, hairy, scaly, or subnaked. .

In the division of the hystricine Rodents into families much diver- sity of opinion has prevailed. Mr. Waterhouse, laying too great stress on dental characters, entirely separated the Dasyproctina from the Caviina, and placed them between the Hystricina proper and the Echimyina*. Prof. Brandt reunited the two former in his family Hemionychoides, equivalent to the Subungulata of Ilhgery. But the group thus formed is so ill defined that Prof. Lilljeborg found it im- possible to separate it from the Hystricidet. It seems to me that, although Mr. Waterhouse was certainly misled in entirely separating the Agoutis and Pacas from the Cavies and Capybara, they must still be ranked as distinct but allied families, and that the same value must be given to the curious form named Dinomys by Dr. Peters§. Accordingly I would recognize six families of the Hystricomorpha.

Of these the first, the Octodontide, consists of three subfamilies ; for here, I think, must be placed the Ctenodactyline, formerly asso- ciated with the Jerboas, but of which the hystricine affinities have been established by Dr. Peters||. The other subfamilies are the Octo- dontine and Echinomyine of Mr. Waterhouse. Some of the genera of the latter make a close approach to the next family, the Hystri- cide, which in its turn is composed of two very distinct subfamilies, Sphingurine and Hystricing ; for 1 cannot follow Professor Lillje- borg in relegating the former to the Octodontide4, principally on account of their better-developed clavicles, which are probably an adaptive peculiarity connected with their arboreal habits. Of the remaining families the Chinchillide form a small but very natural group, connected in some characters with the Dinomyide ; and the latter, again, has close affinities with the nearly allied Dasyproctide and Caviide. These latter families in many points, as in the mode in which their incisors wear down, their emarginated palates, and the large size of their basicranial foramina, show a striking ap- proach to the next great group of Rodents.

The second suborder, GLIRES DUPLICIDENTATI, containing only two families, is clearly less specialized than the first, and appears to be a survivor, representing a comparatively early stage in the develop- ment of the Rodent type. At birth, the upper jaw contains the normal number of incisors; but only the two inner pairs are retained; and of these the second remain very small, and are placed directly be- hind the large middle pair. In the mandible there is never more than