rn age “pa os ~ - gab Gestee he ee eae ere ame en ere ae yp ban een ne NE init asm tates a3 ae ae Sent Sle sme ateen 0 a ne 2 eee vehi anh ab ae an eee erinn he OP Fea ke Ee fee ten ee ee HO parrsnet es 2 eee Ter w.t Kite bP Ae” dee hak t= AMO AP bE > ere 5 ee wort et eee owe eymnaearet. P fone Aa Ae Se cue enn te gene sade sp Veen & Sate elie nd a oes ph eetee Steet m= nome - Naceras my averm ants" 0s OATS tea et tte Oe oe . - (ren Set eos 3 03 7 p yi ‘ a . Se a oe ps. 103 : oer nene ee ese ‘ 7 : a ee aes - - ae ae jeep rine ween Ps a Saag - Se nas ee a? eM ae ES 2s * PROCEEDINGS OF THE GENERAL MEETINGS FOR SCIENTIFIC BUSINESS — OF THE ZOOLOGICAL SOCIETY OF LONDON. 1912. PART ¥: CONTAINING Paces 1 to 240, witH 32 PuLatEs AND 32 TEXT-FIGURES. 7 : Ria enian Inase . logy? ‘\ APR 19 1919 7 W228 2 onal Ni used PRINTED FOR THE SOCIETY, SOLD AT THEIR HOUSE IN REGENT’S PARK. LONDON : MESSRS. LONGMANS, GREEN, AND CO., PATERNOSTER ROW. MARCH 1912. aa [Price Twelve Shillings. } nad LIST OF CONTENTS. 1912, Part I. (pp. 1-240). EXHIBITIONS AND NOTICES. Page Tux Secretary. Report on the Additions to the Society's Menagerie during the months of June, July, August, and September, 1911 .............-.......- Otago Bee Ne t Mr. James Dunsar-Brunron. Exhibition of skins and skull of a Bushbuck from N.E. BERL Seats ells aparece tote casi tte elo tee yy late ale tare ale sc fapn PaiMRemeette can TEN Lt ai a a 4 Mr. W. B. Corron. Exhibition of heads and horns of various species of Gazelles from the Eastern Sudan........- rn Naat ave Neto deles eeheyctals sieve etadeteterteealel: tele stem civiegels etetetmereg Hioie | Mr. D. Suru-Smitu, F.Z.S. Exhibition of a spirit-specimen of a nestling Australian Regent-Bird (Sericudus mefinus). (Text-fig. 1.) .........0-2. Dislsters (cape ane ere eee a oe Mr. R. I. Pococs, F.R.S., F.L.S8., F.Z.S. Exhibition of photographs of, and remarks upon, a new race of Red-fronted Gazelle (Gazella rufifrons hasteri). (Text-figs, 2, 3.).. 5 Mr. J. Lewis Bonuors, M.A., F.L.S., F.Z.S. Exhibition of, and remarks upon, living specimens of Rats (Mus rattus) which showed the “‘ waltzing” character .........- 6 Yur Secretary. Report on the Additions to the Society’s Menagerie during the month of October 1911 .......0... oka doses BOOM e aa tod Shao eine hain wdinie Mihaela eek 142 Mr. RB. I. Pocock, F.B.S., F.L.8., F.Z.S. Exhibition of, awd remarks upon, living speci- mens of the Common Elephant-Shrew (Macroscelides proboscideus) and the Rock ; Blephant-Shrew (Hlephantulus rupestris). (Text-figs. 16, 17.). .- 2.0 ..eceese ce eeee 142 Luz Secrerary. Report on the Additions to the.Society’s Menagerie during the months of November and December 1911 and January 1912 ..... De hls stet oe ceeeee eee 231 Mr. E. G. B. Muave-Watvo, V.P.Z.S. Exhibition of a pale fulvous variety of the Common Polecat (Putorius putorits) .. 0°. ..... ae ence ren crss ce ieee eee 234 Mr. Rosert D. Carson, C.M.Z.S. An account of retarded development of the foetus in a Red Kangaroo (Macropus rufus). . co... es ts Sete Pee Sen EER Oo 9: 234 Contents continued on page 3 of Wrapper. PROCEEDINGS OF THE GENERAL MEETINGS FOR SCIENTIFIC BUSINESS ZOOLOGICAL SOCIETY OF LONDON, 1912, pp. 1-504, wiTH 60 Puates and 63 TExt-FIGURES. ’ PRINTED FOR THE SOCLETY, AND SOLD AT THEIR HOUSE IN REGENT’S PARK. LONDON: MESSRS. LONGMANS, GREEN, AND CO, PATERNOSTHR ROW. of a > 22 Ss (orally OF THE COUNCIL AND OFFICERS OF THE ZOOLOGICAL SOCIETY OF LONDON. Ge COUNCIL. His Grack THE DUKE OF BeprorD, K.G., F.R.S., President. Tur Earp or Auramont, F.S.A. | E. G. B. Meape-Watpo, Esq., Str Joun Rose BRADFORD, Vice-President. - K.C.M.G., M.D., D.Sc.,.| Prof: Epwarp\_A. . MINcHIN,. F.R.S., Vice-President. | M.A., F.R.S., Vice-President. Ricoarp H. Burne, KHsq., | P. CHALMERS MircHewy, Ksq., ( | | | M.A. | MRA. DSc.) scons nieae Lt.-Col. Sir R. Havetock | F.RS., Secretary. Cuartes, G.C.V.O., M.D. _W. R. Octivin-Grant, Esq. Aurrep H. Cocks, Esq., M.A. | AvBpEerr Pam, Hsq. F. G. Dawtrey Drewrrr, Esq., | Aprian D. W. Poxttock, Esq. Mi At Via): | OLDFIELD T'Homas, Hsq., F.R.S. CHartes Drummonn, Esq, AntHony H. WHuINGFIELD, Treasurer. Ksq. Srr Epwarp Duranp, Bt., C.B. | A. Smrra Woopwarpb, Ksq., F. Du Cans Gopmax, Esq., ; LL.D.,F.R.S., Vice-President. IDV Calli aL Mas), | Henry Woopwarp, Esq., LL.D., Sir Epmunp G. Loprmr, Bt., | F_R.S.. Vice-President. Vice- President. PRINCIPAL OFFICERS. | P. Cuaumers Mrrcuenn, M-A.,D.Se., Hon.LL.D., F.R.S., Secretary. Frank E. Bepparp, M.A., F.R.S8., Prosector. R. I. Pocock, F.R.S., F.L.8., Curator of Mammals, and Resident Superintendent of the Gardens. D. Seru-Surru, Curator of Birds and Inspector of Works. Kpwarp G. BouLtencer, Curator of Reptiles. Henry G. Purmer, F.R.S., M.R.C.S., Pathologist. F. H. Waternouse, Librarian. JouNn Barrow, Accountant. W. H. Cour, Chief Clerk. LIST OF CONTENTS. 1912, pp. 1-504. EXHIBITIONS AND NOTICES. Page The Secretary. Report on the Additions to the Society’s Menagerie during the months of June, July, August, and September, 1911 Mr. James DunsBAR-Brunton. Exhibition of skins and skull of Bushbuck from N.E. Rhodesia Mr. W. B. Corron. Exhibition of heads and horns of various species of Gazelles from the Eastern Sudan ... 4 Mr. D. Seru-Surru, F.Z.S. Exhibition of a spirit-specimen of a nestling Australian Regent-Bird (Sericulus melinus). IES a Tia) i ee, EL rk ao 4 Mr. R. I. Pocoox, F.R.S., F.LS., F.Z.S. . Exhibition of photographs of a new race of Red-fronted Gazelle (Gazella rufifrons hasleri). (Text-figs. 2 & 3.) Roa eeececese Mr. J. Lewis Bonnors, M.A., F.L.S., F.Z.S. Exhibition of living specimens of Rats (J/us rattus) which showed the “ waltzing” character The Secrerary. Report on the Additions to the Society’s Menagerie during the month of October 1911 lv Mr. R. I. Pococn, F.R.S., F.L.S., F.Z.S. Exhibition of living specimens of the Common Elephant - Shrew (Macroscelides proboscideus) and the Rock Elephant- Shrew (Llephantulus rupestris). (Text-figs. 16 & 17.). The Srcrerary. Report on the Additions to the Society’s Menagerie during the months of November and December 1911 and January 1912 Mr. E. G. B. Mzape-Watpo, V.P.Z.S. Exhibition of a pale fulvous variety of the Common Polecat (Putorius ULOVIUS) BN cane FRR eel Mea” SS Mr. Rosrrr D. Carson, C.M.Z.8. An account of retarded development of the foetus in a Red Kangaroo (Macro- UST UF US) a, eens ti SNA EET. a Dr. A. T. Masrerman, M.A., F.Z.S. Demonstration of recent investigations on Age-determination in the Scales of Salmonoids Mr. Ouprietp THomas, F.R.S., F.Z.S. The Races of the Buropean Wald’ Sywinmes se an sale eee ee Mr. A. Rapciyrre Duemore, F.R.G.S. Lantern exhibition of photographic studies of wild animals in British East Africa and Newfoundland Messrs. KE. GERRARD & Sons. Exhibition of the head of a cow Sable Antelope, the skulls of an Isabelline Bear, a Leopard, and a Lion, all of which showed some ab- normality DO ICI SO ICICI II Tian iO ICnOiO ni iii oICnOICHO CR MPECIry oie OI OO OOO Od Mr. OxprieLp Tuomas, F.R.S., F.Z.S. Two new Genera and a new Species of Viverrine Carnivora. (Text-figs. GIS GS )iecctstartasetnskneeuncaneenens4).til: 56 Rae ae eee Mr. Guy Dotuman. A new Snub-nosed Monkey 142 231 234 234 390 390 498 498 498 PAPERS. . Distant Orientation in Amphibia. By Bruce F. Cum- mMInGs. (Text-figs. 4 & 5.)..........ccecsceteseereneeeeeeees . Some Remarks on the Habits of British Frogs and Toads, with reference to Mr. Cummings’ recent communi- cation on Distant Orientation in Amphibia. By Cu Aeonmencnn, LR BPE ihe. isos. sessed ecctvee. . Game Sanctuaries and Game Protection in India. By E. P. Srepeine, F.L.S., ¥.Z.8., F.R.G.S. Pere . On the Moulting of an Arctic Fox (Vulpes lagopus) in the Society's Gardens. By R. I. Pocock, F.RS., F.LS., F.Z.S., Superintendent of the Gardens. (Text- GMS ea ta ESN athe s as nsio vice teachable warete cd eeretamte's Sate tara ean ee © . On the Moulting of the King Penguin (Aptenodytes pennanti) in the Society’s Gardens. By Davin Setu- Smirn, F.Z.S., M.B.O.U., Curator of Birds. (Pl. 1.) . . On the Presence of two Ovaries in certain British Birds, more especially the Falconide. By ‘Tl. E. Gunn, ead is a A (A 2) e e ey ee e . On some Collembola from India, Burma, and Ceylon; with a Catalogue of the Oriental Species of the Order. By A. D. Imus, D.Se., B.A., Forest Zoologist to the Government of India; late Professor of Biology, Muir College, and Fellow of the University of Allahabad. (Pls. VI.—XII. and Text-figs. 14 & 15.).. . Ontogenetical Transformations of the Bill in the Heron (Ardea cinerea). By Prof. P. P. Susuxrin, C.M.Z.S., hanmovy teussiae) (Pl. MUM ress ilies ccaesvencoseeses . The Duke of Bedford’s Zoological Exploration of Eastern Asia.—XV. On Mammals from the Provinces of Sze- chwan and Yunnan, Western China, By OLDFIELD SrOMAG) DSuiSee ete. «eres, txec cas eciyincs qotatieesecsuas’ Page 8 19 23 55 60 80 125 127 10. tae 12: 13, 14. 15. 16. 17. 18. Vi The Freshwater Crayfishes of Australia. By GEOFFREY Smirn, M.A., Fellow of New College, Oxford. (Pls. XIV.-XXVII. and Text-fig. 18.) weet erst ees eet ert oesene Structure of the Alimentary Canal of the Stick-Insect, Bacillus rossii Fabr.; with a Note on the Partheno- genesis of this Species. By Atrrep EH. Cameron, M.A., B.Sc., Fullerton Scholar of the University of Aberdeen and Research Student in the University of Manchester. (EIS CNG PIA ONO oe hase peteee wacwine gnosis eee Diagnoses of new Species of Terrestrial and Fluviatile Shells from British and German Hast Africa, with the Description of a new Genus (Hussoia) from Husso Nyiro River, B.E, Africa. By H. B. Preston, F.Z.8.. (Pls. XXXI. & XXXII) POOP ee Pee peepee penpererepeserenesese Contributions to the Anatomy and Systematic Arrange- ment of the Cestoidea.—III. On a new Genus of Tape- worms (Ofiditenia) from the Bustard (Hupodotis kort). By Frank EH. Bepparp, M.A., F.R.S., F.Z.S., Prosector TO Ne ores” (bettie NO 30))) son sannodoonanonocosoes On the Milk-Dentition of the Ratel. By R. Lyppxxmr. (Text-figs. 31 & 32.) Ceo meme ee meee ns eet pen per ese pero eseeeneroee On a Further Collection of Mammals from Egypt and Sinai. By J, Lewis Bonnors, M.A., F.L.S., F.Z.8. ... Report on the Deaths which occurred in the Zoological Gardens during 1911. By H. G. Puimer, F.R.S., F.Z.8,, Pathologist to the Society CC i a eC CC eC eC nC ery Mendelian Experiments on Fowls. By J.T. Cunnine- SEAM RIVA IM ZiS, Mean atc ct mermcan tie. cc mete aece eee Studies on Pearl-Oysters and Pearls.—I. The Structure of the Shell and Pearls of the Ceylon Pearl-Oyster (Margaritifera vulgaris Schumacher): with an Examin- ation of the Cestode Theory of Pearl-Production. By H. Lysrer Jameson, M.A., D.Sc., Ph.D., F.Z.5. (Pls. XXXIIT.-XLVII. and Text-figs, 33-41.) ...........0005 Page 144 172 183 194 221 235 241 260 vil Page 19. Mimicry amongst the Blattide; with a Revision of the Genus Prosoplecta Sauss., and the Description of a new Genus. By Rospert SuHetForp, M.A., F.Z.S. (PI. SU Wem, Vext-fgs. 42-46.) oo. cccccecc esse cesccweses 358 20. On the Pairing of Pseudoscorpiones. By H. WaAt..is Wee ( bext-fias, 47-50.) <2. ccc heccscdenceesves 376 21. A Contribution towards the Knowledge of the Spiders and other Arachnids of Switzerland. By the Rev. O. PiIcKARD-CAMBRIDGE, M.A., F.R.S., C.M.Z.S. (Text- La ema) eer pg he eet eg Oth acca ied ale aye Sls s ses 393 bo bo . On the Blood-parasites found in Animals in the Zoological Gardens during the four years 1908-1911. By H. G, Pumwer, F.RS., F.Z.8., Pres.R.M.S., Pathologist to the Society. (Pls. XLIX.—LY.)......... 406 23. On the Structure of the Internal Ear and the Relations of the Basicranial Nerves in Dicynodon, and on the Homology of the Mammalian Auditory Ossicles. By he Broom, M2D., D:se, CMZ.S8. (Pl LVE and Pee tite, clel Aies Ne ey tem care Pataca eee sa wr yaice ce eta es 419 24. Zoological Results of the Third ‘Tanganyika Expedition conducted by Dr. W. A. Cunnington, 1904-1905. Report on some larval and young stages of Prawns from Lake Tanganyika. By Prof, G. O. Sars, C.M.Z.8. ae vlistae Wig Tele Wea yates narra cree n Qenet rail bene ny aticoie cake 426 25. The Classification, Morphology, and Evolution — of the Echinoidea MHolectypoida. By Herserr L. Hawkins, M.Se., F.G.S.; Lecturer in Geology, Uni- versity College, Reading. (Text-figs. 54-60.) ......... 44() mignabetical List of Comtributors: 22100........0-scenseenes ees, 1X New Generic Terms ...... sista SRR ace Rew sield eu acsiein akeatip XV1 LAER OMSCLEMUMIC NEES? « \.4cces emesis aa cae oboe bcos cele ae ates aes XV1L Index of Illustrations ..... NP nineties OE re eS xxix ri) Rahiperny We ee Fre 1 ns Ur a Ree he MR RABIN wae iie| heey hate a io PER OB Hein ith ye RY me by ede | ye ti RE BA my Bagh ee ie ae Loe 5 Mein a (ay f pg ih F d epit : Fie 3 eae ee t a f i i i & i J t j ei inf 9 Bie ‘ Rr ke i ‘ ean | Prise a! Grbry ee if Ce E i i wh Lh \ ee ® | tel r ue iy I j q, fel Th AGE AT oh ro Cae Me ; Lk Ei ita Cy Pe a : ; ‘ ; ye REN ni: i jae ig 4 ce ele 4 if yr i Rel / i ! ies’ ay & pee , hes ve at ‘ Ww Perea iy ial Hise al Heiss bytes me i LD) ‘ji aie oe ents wal Eerie Nah a o hey rae AR Lee a veaay ign? ee es eal - OT LG _ OT had a a he. aye Se Ee a oes «a vdks 406 Pocock, Reernaxp I., F.R.S., F.L.S., F.Z.8., Superintendent of the Gardens and Curator of Mammals. Exhibition of photographs of a new race of Red-fronted Gazelle (Gazella rufifrons hasleri). (Text-figs. 2& 3.) ... 5 On the Moulting of an Arctic Fox (Vulpes lagopus) in the Society’s Gardens. (Text-figs, 6-13.) ...........ccanes DD X1V f Page Pocock, Rreeraxp, I., F.R.S., &e. (Continwed.) Exhibition of living specimens of the Common Ele- phant-Shrew (Macroscelides proboscideus) and the Rock Hlephant-Shrew (Hlephantulus rupestris). (Text-figs. UG ree MUTE tas Or cere been eects. tality acae caine des. 5's 1 ae eee 142 Preston, HucutB., F.Z.8. Diagnoses of new Species of Terrestrial and Fluviatile Shells from British and German East Africa, with the Description of a new Genus (Hussoia) from the Husso Nyiro River, B. EH. Africa. (Pls. XXXI.& XXXII.)... 183 Sars, Prof. Grorce O., C.M.Z.8. Zoological Results of the Third Tanganyika Expe- dition, conducted by Dr. W. A. Cunnington, 1904— 1905.—Report on some larval and young stages of Prawns from Lake Tanganyika. (Pls. LVII.-LX.) ...... 426 Seru-Smira, Davip, F.Z.S., M.B.O.U., Curator of Birds and Inspector of Works. Exhibition of a spirit-specimen of a nestling Australian Regent-Bird (Sericulus melinus). (Text-fig. 1.) ............ 4 On the Moulting of the King Penguin (Aptenodytes pennants) in the Society's Gardens. (PI. 1.) ...0..c.. 60 SHELFORD, Rospert, M.A., F.Z.S. Mimicry amongst the Blattide; with a Revision of the Genus Prosoplecta Sauss., and the Description of a new Genus. (Pl. XLVIII. and Text-figs. 42-46.) ...... 358 SairH, D. SerH-. See Seru-Smirn, D. Smira, Georrrny, M.A., Fellow of New College, Oxford. The Freshwater Crayfishes of Australia. (Pls. XIV.— POG V lle enalMoxt snes). le ee ee ene cae 144 Ey, STEBBING, Epwarp P., F.L.S., F.Z.S., F.R.G.S. Game Sanctuaries and Game Protection in India ...... SusHKIN, Prof. Perer P., C.M.Z.8., Kharkov, Russia. Ontogenetical Transformations of the Bill in the Heron (Ardea cinerea). (Pl. XITI.)...... ook Bete See See ar eae Tuomas, OLDFIELD, F.R.S., F.Z.8. The Duke of Bedford’s Zoological Exploration of Eastern Asia.—XV. On Mammals from the Provinces of Sze-chwan and Yunnan, Western China.................. The Races of the European Wild Swine .................. Two new Genera and a new Species of Viverrine eranivoie.,\, (hext-les, 61—Odalamgr em amete sss -0h.e.. faces Wanpo, E. G. B. Meaps-. See Mrape-WAxpo, E. G. B. Page bo oS — iS) i | NEW GENERIC TERMS PROPOSED IN THE PRESENT VOLUME (pp. 1-504). Page © Page Chrotogale (Mammalia)......... 499 | Idiomerus (Collembola) ...... 113 Conulopsis (Echinoderma) ... 453 | Megapygus (Echinoderma; ... 449 Dicranocentroides (Collembola) 102 | Melyroidea (Orthoptera) ...... 374 Diplogale (Mammalia) ......... 499 | Otiditeenia (Vermes) ............ 220 Eussoia (Mollusca) ............ 192 | Paracheraps (Crustacea) ...... 161 Heteromuricus (Collembola)... 92 | Pseudocyphoderus (Collembola) 116 SCIENTIFIC Accipiter nisus, 67, 70-74, 79. Achorutes armatus, 81, 85, 119. crassus, 119. hirtellus, 119. lipaspis, 119. Achroblatta luteola, 361. Acomys cahirinus, 229. russatus, 224, 229, 230. ¥ we yptiacus, 230. — 224, sellysit, * 224, Acrobothrium, 274, 279. Adelopneustes lamberti, 458. /Elureedus melanocephalus, 408. /élurops v-insignitus, 402. Aétobatis narinari, 274, 283, 284, 289, 291, 358. Africarion kemp?, 184, 193. microgranulata, 184, microstriata, 184, 193. Agapornis taranta, 238. Agelena | labyrinthica, 396. Alza | keniana, 189, 193. Algiroides nigropunctatus, 412. Allacta, 367. | Alligator mississippiensis, 415, | sinensis, 233. | Proc. Zoou. Soc.—1912, | Anomotvnia, 219, 220, | Anoplotznia, 208, 209, | Anthus INDEX OF Amadina Jasciata, 416. Amaurobius Senestralis, 396. ferox, 396. 4-guttatus, 396. Amblyornis subalaris, 411, 416. Amblypygus, 453, 454, 470, 491, 493. | Amphibolurus barbatus, 410. Amydrus moriv, 233. Anamesia, 359. Anaplecta, 367. decipiens, 365. vartipennis, 366. Anas sparsa, 1. Anchitherium, 221. | Ancylus kempt, 190, 193. Andigena bailloni, 409. | Anisolemnia distaura, 376. Anodonta, 301, 316. isacantha, 210. pen icillata, 210. 210, 221. Anorthopygus, 443-445, | 447, 458-467, 473- | 475, 478-480, 486, 490, 493. orbicularis, 449, 456, 467, 491. Anoura, 85. | Anourosorex | squamipes, 134. maculatus, 5. | i No. XXXII. NAMES. Anthus rosaceus, 3. Anura, 85. Aphelocoma ultramarina, 408. Apodemus agrarius, 135, chevrieri, 135, 136. — fergussoni, 135, 136 draca, 137. JSergussoni, 135, 136. orestes, 137. peninsule, 137. speciosus, 136, 137. — chevrieri, 136. — latronum, 137. — orestes, 136, 137. — peninsule, 136. — peninsularis, 137. Aptenodytes pennanti, GO. Aptera Jusca, 360. Ara macao, 415. Arzoncus altissimus, 398. Arctonyx obscurus, 134. Ardea cinerea, 125, 126. | Areolaria, 361. bipunctata, 369. Asagena phalerata, 397. Asio accipitrinus, 3, 73. | Aspergillus niger, 239. Assimania aurifera, 191, 193. Astacoides, 148. bicarinatus, 163. 33 XVill Astacoides plebeius, 157. serratus, 157. spinifer, 157. Astaconephrops albertisti, 167, 168. Astacopsis, 150, 151, 1153}, australiensis, 159, 160. bicarinatus, 163. Ffranklinii, 145, 146, 148, 152, 154, 156, 160, 161, 170, 171. — tasmanicus, 146, 149. kershawi, 146, 149, 152, 160, 161, 170. nobilis, 157, 159. paramattensis, 159. serratus, 145, 146, 147, 149, 152, 157, 159, 160, 161, 170, 171. — yarraensis, 152. spinifer, 157, 159. sydneyensis, 157, 159. tasmanicus, 156. Astacus, 144, 488. armatus, 157. australiensis, 157. bicarinatus, 163. Asterostoma, 448. Ateles geoffroyt, 407. paniscus, 3. Atemnus, 388. Atheris chlorechis, 414. Attulus histrio, 402. Attus pubescens, 402. rupicola, 402. Aulacocheilus, 372. Aulonia albimana, 401. Avitellina, 208. centripunctata, 216. 157 } 207, Bacillus gallicus, 172. granuatus. 72. rossti, 172-182. Balzeniceps, 126. Balanoglossus, 281. Balearica regulorum, 415. Balistes, 261, 286, 287, 288. Bathyphantes concolor, 397. variegatus, 397. Bauria, 423. Bertiella cercopitheci, 195. Bitis arietans, 413. Blarinella quadraticauda, 134. Blatta germaniea, 181. Blattella germanica, 304. Blauneria exsilium, 189, 193. Boa constrictor, 413. madagascariensis, 414. Bolyphantes alticeps, 397. Bos gaurus, 30. Bubo capensis, 416. maculosa, 417. poensis, 417. Bufo calamita, 19. marinus, 410, 413. regularis, 414. vulgaris, 9, 19. Buteo vulgaris, 7. Caccabis chukar, 41. Calabaria reinhardtt, 230. Calandrelia acutirostris, 3. Callilepis nocturna, 39D. Calliope camtschatkensis, 2. Calliptilus solitarius, 232. Calliste cayana, 409. cyanoptera, 408, 416. Jestiva, 416. Hlaviventris, 409. guttata, 408. melanonoia, 416, thoracica, 415. tricolor, 416. Caloblatta, 361. Calopelia puella, 416. Cambarus, 144. INDEX OF SCIENTIFIC NAMES. Cam pylothorax, 108. Cancer serratus, 157. Canis zerda, 225. Capricornis milne-edwardsi, 141. Caratomus, 448, 453, 492, 497. Cardinalis pheniceus, 409. Caridella cunningtont, 430, 439. Caridina nilotica, 427, 430, 431. — gracilipes, 426. wyckti, 426. Carpodacus meaxicanus, 415. Carpophaga concinna, 415. Caryomys, 139, 140. Cassiculus melanicterus, 416. Cassida, 362. Cassidodes ligata, 371. Cebus albifrons, 407. Jatuellus, 3. hypoleucus, 233. Centromerus affinis, 397. subalpinus, 397. Cephalobothrium, 285. abruptum, 284. aétobatidis, 284, 358. variabile, 284. Cephalophus coronatus, 232. Ceratameria (Schottella) maxiina, 119. Ceratinella brevis, 398. Ceratinoptera, 367. Cercidia prominens, 399. Cercopithecus sabeus, 410, 415. tantalus budgett?, 142. Ceryvulus muntjac, 3d. Cervus axis, d2. duvaucelt, 35. eldi, 41. kashineerianus, 232 porcinus, 32. unicolor, 26. xanthopygius, 142. Cheraps, 145, 148, 151, 152, 153, 160, 162, 169. arwanus, 168. bicarinatus, 163. intermedius, 150, 165, 168, 171. lorentzi, 168. preissii, 263. quadricarinatus, 158, 167, 168, 171. — aruanus, 167. — lorentzi, 1@7. quinguecarinatus, 165, 171. tenuimanus, 166, 170, Chameleon senegalensis, 418. Chapmannia lapica, 195. Cheiracanthium ttalicum, 396. Cheiracanthus uncinatus, 266. Chelifer, 388, 390. cimicoides, 377. cyrneus, 377, 381, 382, 384, 486, 387. latreillii, 377, 880, 382, 385, 386. multidentatus, Chernes, 377, 382, 387, 388, 390. Chironomus, 176. Choanotznia, 217, 219. galbuia, 202. infundibulune, 220. levigata, 220, Chodsigoa berezowskii, 133. hypsihia, 133, 134. larvarum, 183. Cholcepus hoffmanni, 1. Chorisoneura, 367. teniata, 360. Chrotogale, gen. neyv., 387, 202, owstont, 500, 501, 502. Chrysemys ptota, 415, 415. Chrysomitris cucullatus, 416. tibetana, 2. Chrysomma sinense, 409. Chrysotis vantholora, 233. INDEX OF SCIENTIFIC NAMES, | Chthonius, 381, 388. tetrachelatus, 403. Cicinnurus regius, 408, 416. Cieurina cinerea, 396. Cidaris, 441, 46]. Cinixys belliana, 413, Circaétus gallicus, 73, Circus eruginosus, 72, '73, 76, 79. cineraceus, 79. cyaneus, 71, 72, 73, 76, 79. LOT G: macrurys, 73. Gistudo carolina, 411. Cittoecinela macrura, 409, Clemmys guttata, 414. leprosa, 413. Clione, 266. Clubiona hilaris, 396. Clypeaster, 445, 457, 462, 479, 492, 493, 494. Clypeus, 464. Coccothraustes melanura, 415, Ceculus echinipes, 403. Coelophora formosa, 373, 376. Ceelotes atropus, 396. claustrarius, 396. pickardii, 396. terrestris, 396. Ceenholecty pus, 447, 451, 455, 464, 466, 467, 472, 475, 479, 480, 486, 487, 493. Jjullient, 467. macropygus, 430. Coereba cyanea, 417. Colinus pectoralis, 3. Gvlobus matschiei, 142. Coluber corats, 412. guttatus, 413. leopardinus, 41 1. 409, 416, Xix Coluber longissimus, 413. nelanaleucus, 413. ohsaletus, 413. vulpinus, 2. Columba gymnophthalma, 409. Conoclypeus, 445, 453, 456, 460, 462, 468, 469, 492, 493, 494. Conylopsis, gen. nov., 453, 469, 491, 492, 493. roemert, 453, 495. Gonulus, 447, 454, 457- 460, 464-480, 487, 490-4938, 497. alhogalerus, 451, 455, 462, 48]. subconious, 482. suhratundus, 456, 461, 462, 486. Copsychus sauaris, 409, 411, 416. Coptodiscus, 447, 467. 472, 486, 493. neme, 450. Coracias indica, 417. Corallus cooki, 414, Covronella getula, 412. Corvus, 70. Srugilegus, 73. Corydia, 361. petiverana, 362. Corynephoria Jjacabsoni, 121. Cosmozasteria lateralis, 359. zonata, 359, Crateropus platycercus, 3. Cremastocephalus eelebensis, 120. indicus, 81, 104, 105, 106, 120, 124. montanus, 81, 105, 106, 120, 124. Crocidura attenuata, 184, — (Crocidura) religi- osa, 225, Cratalus atrox, 412. confluentus, 414, horridus, 413, Crypheeea silpicola, 396, aa xx INDEX OF SCIENTIFIC NAMES. Curzeus aterrimus, 409, Cyanocitta stellert azteca, 232. Cyanocorax luxuosus, 409. Cyanospiza leclancheri, 415. Cyathocephalus, 274, 280. Cyathophyllus, 274. Cyclemys trifasciata, 411. Cyclosa conica, 398. Cyclura acanthura, 410, 418. Cygnus bewicki, 72, '78, 79. Cylindrophorus, 199. Cynezlurus jubatus, 2. Cyuips kollari, 174. Cynixis belliana, 415. erosa, 416. homeana, 415. Cynognathus, 4238, 424, | 425, Cyornis rubeculoides, 2. Cyphoderodes, 116. ceylonicus, 121. Cyphoderus albinus, 115, 116. javanus, 121. simulans, 81, 115, 116, | 121, 125. Cyrtomorphus, 372. Dacnis cayana, 415, Damonia reevest, 413. Davainea, 216. comitatus, 218. frontina, 218, lateralis, 220. rhynchota, 218. Degeeria, 99. Delphinognathus, 428. Dendraspis viridis, 233, 414. Dendreeca coronata, 142, Dendryphantes encarpatus, 402. Deropeltis dichroa, 360. 142, 409, | Dicranocentroides, Deropeltis erythrocephala, 360. paulinoi, 360. Desorella, 448, 454, 490. | Desoria, 443. ; 485, Diademopsis, 484, Dizea dorsata, 399. Dichoceros bicornis, 238. gen. noy., 82, 102, 121. Ffasciculatus, 81, 102, 120, 128,124. | Dictyna flavescens, 396. uncinata, 396. viridissima, 396. | Dicynodon, 419, 424. latifrons, 420. Didelphys nudicaudata, 407. | Dilepis, 218. | Diplocephalus castaneipes, 398. eristatus, 398. eborodunensis, 398. Rochii, 398. Diplogale, gen. 499. hosei, 499. Diploptera dytiscoides, 361, 366. Dipeena braccata, 3897. Dipsas plicatus, 317. Dipus gerbillus, 226. Discoholectypus, 487, 491, 493. meslei, 451. noy., 470, | Discoidea, 443-447, 454, 458-460, 462, 464, 466, 468-471, 474— 77, 479-481, 487, 490, 492-494, cylindrica, 455-457, 461, 496, 497. subucula, 451, 452, 472, 478, 497. Distomum margaritifactor, 274. Dolomedes jimbriatus, 400. Drapetisca socialis, 397. Drassodes lapidosus, 395. pubescens, 395. Drassus hispanus, 395. troglodytes, 395. Drymobius boddaerti, 418. Dryotriorchis spectabilis, 409. Dymecodon, 130, 131. Echinanthus, 445. Hehinites, 452, 477, 494. Echinobrissus, 489. Hehinocardium, 441. Echinoconus, 4438, 445, 453, 495. abbreviatus, 492. conicus, 496. orbignyanus, 492. | Echinocorys, 478. | Hchinocyamus, 477, 478, 493, 494. Echinolampas, 454, 474, 493. Echinoneus, 448, 444, 452, 459, 462, 467, 490, 497. Echinus, 474, 476. Kelectus pectoralis, 416. Ectobius, 365, 366. Elaphodus cephalophus, 141. Elephantulus rupestris, 142, 143, 144. Emberiza elegans, 2. Fucata, 3. leucocephala, 3. Emys lutaria, 411. orbicularis, 4138. Engeus, 145, 148, 15], 152, 153, 160, 162, 165. Eniochobothrium gracile, 284. Ennea microstriata, 183, 193. Enoploenatha thoracica, 397. Entomobrya anomala, 97. crassa, 81, 96, 128. florensis, 120. halt, 8, 95, 120) 1123: — lutea, 81, 96. longicornis, 120. | Entomyza cyanotis, 408. Eos fuscata, 2. Eothenomys, 159. Epeira adiana, 399. agalena, 399. alpica, 399. earbonaria, 399. ceropegia, 399. circe, 399. cucurbitina, 399. diademata, 399. dioidea, 399. marmorea, 399. montana, 399. nordmannii, 399. pyramidata, 399. quadrata, 309. redti, 399. sclopetaria, 399. sturmiti, 399. triguttata, 399. Epiblemum scenicum, 402. Epimys confucianus, 135. humiliatus, 135. norvegicus, 135, 411. Episinus truncatus, 396. Equus kiang, 2. Erigone atra, 398. dentipalpis, 398. Jugorum, 398. remota, 398. tirolensis, 398. Erythrura pealet, 2, 142. prasina, 499, 416. psittacea, 416. Eryx johni, 414. Estrelda melpoda, 408, +11, 415. phenicotis, 408. Eumorphus, 362. Euophrys ae 402. Frontalis, 402. petrensis, 402. pictilis, 402. Eupatagus, 475. Euphonia . laniirostris, 409. violacea, 408. Euplectes franciscana, 409. oryx, 416. Eupleres, 499, 502. INDEX OF SCIENTIFIC NAMES, Eupodotis kori, 194, 220, 221. Eupsychortyx nigrigularis, 232. Eurycotis floridana, 859, 360. Euryopis flavomaculata, 597. Eussoia, gen. nov., 183, 192. inopina, 192, 193. | Eustegasta buprestoides, 361, 362. Huzoéa, 427. Euzosteria mitchelli, 359. Falco, 70. esalon, 73. cenchris, 73. peregrinus, 72, 77, 79. sudbuteo, 72, 73, 77, 79. tinnunculus, 71, 72, 73, COD vespertinus, 73. | Felis leo, 498. nebulosa, 3, 224. onca, 224. pardalis, 3, 224. pardus, 224, 498. sylvestris, 232. temmincki, 407. tristis, 224. Forficula, 178. Francolinus gariepensis, 408, 411. levaillanti, 409, 411, 417. Fuligula baeri, 416. marila, 417. Gadopsis marmoratus, 156: Galago crassicaudata, 233. Galeopithecus, 220. Galeoscoptes carolinensis, 409. | Galerites, 443, 445, 491. albogalerus, 496. roemeri, 453, 492. Galeropygus, 443, 445, 452, 454, 457, 464, 465, 469, 4738, 474, 489. agariciformis, 455. dumortier?, 488. Galictis, 222, 223, 224. XXx1 ' Gallinula | chloropus, 217. | Gallus bankiva, 241, 251, 252, 258. | Garrulax albogularis, 409. leucolophus, 408, 415, | Garrulus lanceolatus, 407, Gazella dorcas, 4. isabella, 4. rujifrons, 4, 5, 6. — hasleri, 5, 6. subgutturosa, 3. tilonura, 4. Genetta poénsis, 142. tigrina, 233. Geocichla citrina, 408. Geopelia striata, 410. Gerbillus gerbillus, 226. pyramidum, 225, sellysit, 226. Gerrhosaurus nigro-lineatus, 1. validus, 1. Ginglymostoma, 282, 285 concolor, 287, 288, 289, Globator, 4438. Glugea, 272. Gnaphosa badia, 395. molesta, 395. petrobia, 395. tigrina, 399. Gonatodes vittatus, 3. Gongylidium apicatum, 398. Goniocidaris, 472. Gracula religiosa, 415. Grus Jjaponensis, 417, — monachus, 2. Gubernatrix cristata, 408. Gymnophallus, 327, Gymnorhina leuconota, 410, 416. tibicen, 408. Hamoceystidium, 415, Xx Hemoproteus danilewskyi, 240, 414, | 415, 416, 419. Haplodiseus, 211. Harpactes drassoides, 395. Hedymeles ludovicianus; 416. Heliophanus @neus, 402. metallicus, 402. Helix zanguebarica, 186. Hemigale hosei, 498, 499. Hemigalus, 499, 503. hardwickei, 498, 580, o01, 502. Hemipedina, 482, bonei, 484, 485. Wemithyrsocera sp., 364, 367. Heuiitragus hylocrius, 26: Hemixus flavala, 409: Herpestes albicauda, 225: Hestia, 368. Heteraster, 469. Heterodon stmus, 411, 413. Heteromuricus, gen, nov., Sil BEA UAE cercifer, 81, 92, 120, TPA, eB}. Heteromurus teneicornis, 120. tetracantha, 120. (Lempletonin) sp., 120. 409; Hexaimitus, 411. Hilaira montigena, 397, Hipposideros armiger, 128, Hippotragus niger, 498. Holaster, 480, Holectypus, 448, 445, 447, 454-463, 465, 468, 470, 472, 475 476, 480, 481, 486, 487, 498. depressus, 450, 455, 463, 464, 466, 471, 478-475. hemisphericus, 463, 464, 466, 475. oblongus, 456, INDEX OF SCIENTIFIC NAMES. Holectypus sarthacensis, 4°77. Holocompsa, 862. Homalenotus quadridentatus, 402. Homopteroidea nigra, 362. Homorus iredalei, 189, 193. Houbara macqueent, 416. Hysena crocuta, 232: Hyboclypus, 443, 444, 446. Hydraspis hilarii, 414, Hyla arborea, 411. goughi, 2. rubra, 2. venulosa, 2, 410, 411. Hymenolepis ambiguus, 195. tetracis, 195. villosa, 198. Hypercompsa Jieberi, 362. Hyphantornis spilonotus, 416. Hypnorna, 361. amena, 362. Hyptiotes paradorus, B98. Icterus baltimore, 409. gularis, 400. Jamuicat, 408, 415. Idiogenes otidis, 195. Idiomerus, gen. noyv., 82, IIS}, PAT pallidus, 81, 114, 121, 124. Iguana tuberculata, 414. Isotoma crassicornis, 119. nigropunctata, 81, 90, 119, 122. palustris, 9B. quadrioculata, 91. sita, 81, 89, 122. Isotomurus palustris, 81, 98, 120, 22, — tricuspis, 120. Ithagenes cruentus, 2. Kaliella consobrina, 193. depauperata, 186, 193. iredalei, 187, 193. higeziensis, 187, 193. Karyolysus, 412. Kistecephalus chelydroides, 422. Kystocephalus translucens, 284, 291. 186, 187, Lacerta ocellata, 414. peloponnesiaca, 414, Lachesis lanceolatus, 412. Lagonosticta senegala, 409. Lagopus scoticus, 72, 77, 79. Lam protornis enews, 415. Lanieria, 447, 487, 498. lanier?, 450. Lanius collurio, 401. Larus minutus, 72,78; 79. Leis dunlopi, 376. Leistes gwianensis, 411. Lemur coronatus, 407. mungos, 407. Leontocebus edipus, 407. rosalia, 407: Lepidocyrtus braveri, 120. gavanicus, 120, javanus, 120. maxtinus, 94. robustus, 81, 84, 120. variabilis, 120. Leptophis liocercus, 418. Leptyphantes expuncta, 397. Sragilis, 397. leprosus, 397. mengit, 397: minutus, 397. pulcher, 397. tenebricola, 397. tenuis, 397. Lepus egyptius, 231. sinaiticus, 280. INDEX OF SCIENTIFIC NAMES. Leucochiloides chanlerensis, 188, 1958. gaziensis, 188, 193. tredalei, 188, 193. soror, 188, 198. Leucodore, 266, 315. Limnea kempi, 190, 193. Limnocaridina parvula, 452, 485, 440. spinipes, 427, 459. Linyphia emphana, 397. JSrutetorum, 397. hortensis, 397. marginata, 397. montana, 397. phrygiana, 597. pusilla, 397. triangularis, 397. Liobunum limbatum, 402. rotundum, 402. Lithyphantes corollatus, 397. paykullianus, 397. Locusta, 178. Lophocarenum nemorale, 398. stramineum, 398. Lophophaps leucogaster, 408. Lophorhina minor, &, Lophortyx douglasi, 3. Lorieculus galgqulus, 416. Lorius domicella, 417. Lycaon pictus sharicus, 142. — — somalicus, 232, Lycosa accentuata, 401. agrestis, 401, albata, 401. amentata, 401. bifasciata, 401. blanda, 401. cursoria, 401. JSerruginea, 401. giebeli, 401. ludovica, 401. lugubris, 401. miata, 401. monticola, 401, nigra, 401. paludicola, 401. | Lycosa palustris, 401. pedestris, 401. pulverulenta, 401. riparia, 401. tarsalis, 401. torrentum, 401. wagleri, 401. Lynchia maura, 416. Macaea, 128. Machlolophus xanthogenys, 2, 417. Macropus bennetti, 232. rufus, 234, 235. Macropygus, 447, 452, 463, 464, 466, 475, 485, 493. macrocyphus, 468. morrisit, 479. truncatus, 449, 488. Macroscelides proboscideus, 142, 148, 144. Macrotoma vulgaris, 91, Manucodia atra, 409. Margaritana, 500, 312, 322, 327. Margaritifera, 303, 304, 316, 323. margaritifera, 310, 811, 318, 347, 351. — cumingti, 260, 274, 275, 299, 348. — mazatlanica, 339. martensii, 317. maxima, 261, 295, 305, 306, 307, 318, 347. vulgaris, 260, 261, 262, 268, 273, 274, 277, 278, 291, 292, 293, 295, 296, 298, 302, 306-309, 311, 314, 327, 328, 329, 331, 332, 337-341, 345- 349, 352-355. Megabunus rhinoceros, 402. Megalema asiatica, 409. Megapyga eximia, 376. Megapygus, gen. nov., 447, 449, 452, 457, 464, 466, 469, 479, 480, 486, 490, 493. XX1l Megapygus umbrella, 495. Melanerpes uropygialis, 3. Meleagrina margaritifera, 295. Mellivora, 221-224. Melospiza georgiana, 232. pusilla, 409. Melyroidea, gen. nov., O74. magnifica, 375, 376. 449, 485, mimetica, 874, 379, 376. Meriones crassus, 224, 226, 227, 228. — pallidus, 226, 227. — sellysii, 226, 227. melanurus, 227. sellysti, 224. shawi, 226, 227. — melanurus, 227. Merula albocincta, 409. castanea, 2. tamaulipensis, 3. Merychippus, 221. Mesira, 100. Meta menardi, 398. meriane, 398. segmentata, 398, Micaria breviuscula, 395. hospes, 399. pulicaria, 395. scenica, 395. Micrommata virescens, 400. Micromys pygmeus, 137. Microneta rurestris, 398. viaria, 398. Microtus agrestis, 159. eva, 140, 141. irene, 138, 139. melanogaster, 159, 140. millicens, 138. sikimensis, 159. (Caryomys) alcinous, 140. (—) eva, 140, 141. (Eothenomys) smelano- gaster, 140. (—) — eleusis, 139. (—) olitor, 139. ’ XX1V Micryphantes gulosa, 397. Mimeusemia ceylonica, 863. Mimocichla rubripes, 408. Misumena vatia, 399. Modiola, 301. Molge cristata, 8, 10. palmata, 8. Molothrus pecoris, 408. Monieza, 207. Monopylidium, 218, 219, 220. cayennense, 217. infundibulum, LNG. macracanthum, 217. marchali, 217. rostellatum, 217. secundum, 217. Moschops, 423. Moschus sifanicus, 141. Motacilla feldeggi, 2. Mungos albicauda, 225. Mus alexandrinus, 7. chevriert, 135. gentilis, 228. musculus, 228. — gentilis, 228. ouang-thome, 135. plumbeus, 135. rattus, 6, 7, 228. — alexandrinus, 228. — tectorwin, 6, 7, 228. rufifrons, 6. tectorum, 7, 228. Muttua margaritifere, 327. Myiophoneus temmincki, 407. Myiozetetes similis, 3. My liobatis maculata, 284. Myrmecophaga tridactyla, 407. Mysis, 426. Mytilus, 266, 275-278, 300, 301, 316, 324, 348. 216, 6, 270, 272, 293, 294, 306, 308, 336, 347, Mytilus edulis, 267, 307, 327, | 302. Myzantha garrula, 408. Nemorhedus cinereus, 141. Naia tripudians, 411, 413. Nasillus gracilis, 129, Natalina permembranacea, 188, 193 Neanura corallina, 81, 85, 87, 88, 119, 1122: fortis, 119. mtermedia, 81, 87, 88, 1P9) 1122: pudibunda, cela}, IIS), Tey Nemastoma dentipalpe, 403. quadripunctatum, 403. Nematogmus sanguinclentus, 398. Nesoceleus Sernandine, 232. Nettium torquatum, 142. Neurotrichus, 131. Nucifraga caryocatactes, 415. Nucleolites, 489, 493. Nucleopygus, 443, 490. Nyctalus labiatus, 129. plancyt, 129, Obisium, 388. qugorum, 403. Odontophorus capueira, 410, Cidemia nigra, 409. Oides biplagiata, 300, 376. | Oligolophus morio, 402. — alpinus, 402. — glacialis, 402. — palliata, 402. Onychiurus (Lipura) fimetarius,119. } Onychogale frenata, 407. Oochoristica, 217, 81, 86, 87, | INDEX OF SCIENTIFIC NAMES. Ophiosaurus apus, 414. Orchesella, 113. Oreoneta fortunata, 397. Oreospiza chlorura, 409. Orthopsis, 471. Ostrea, 301. Otaria pusilla, 2. Otiditenia, gen. nov., 196, 220. eupodotidis, 194-221. Otoeyon megalotis, 232. Oudemansia cerulea, 119. Oudenodon kolbei, 422, 425. Oviclypeus, 453. Pachnepteryx, 361. Pachyclypeus, 443, 445. Pachygnatha degeerti, 398. Pachyrhynchus, 368. Palemontes varians, 438. Palinurus, 145. Paracheraps, gen. nov., 145, 148, 151, 16n, 165, 168. bicarinatus, 145, 150, 152, 153, 162, 163, 169, 170, 171. Paradisea raggiana, 408. Paranephrops, 144, 167. Parastacus, 144. | Paratropes, 361 Pareiasaurus, 421. Paronella bornert, 81, 106, 114, 120, 124. dahlii, 106. gracilis, 81, 109, 120, 124. insignis, 81, 112, 120, 124, 125. phanolepis, 81,110, 124. travancorica, 81, 108, 124, Parotia lawesi, 408, 417. Passer arcuatus, 417. Patella, 476. | Pecten, 301. Pelecanus roseus, 1. INDEX OF SCIENTIFIC NAMES, Pellenes lapponicus, 402. Pelmatosilpha, 359. Periplaneta, 178. Sortipes, 359. orientalis, 181. Perisphaeria, 363. Phalangium brevicorne, 402. opilio, 402. parietinum, 402. Phasianus Sormosanus, 3. Phileus chrysops, 402. Philodromus alpestris, 400. collinus, 400, emarginatus, 400. laricium, 400. lividus, 400. margaritatus, 400, Philodryas schotti, 233. Pholeus phalangioides, 396. Phonipara canora, 415. Phonygama chalybeata, 408. Phoraspis, 361. Phyllodromia, 178. Phyllonethis lineata, 397. Pileus, 443, 444, 447, 463-466, 469, 474, 476, 485, 486, 4938. pileus, 449. Pinna, 302, 308. Pionopsittacus pileatus, 408. Pirata latitans, 400, Pisaura mirabilis, 400. Pitangus derbianus, 3. Pithecus, 128. Pithodia, 494. Pituophis sayi, 410, 413. Placuna, 273, 274. placenta, 260, 299, 345, 348, 351. Planispira, 185. Planorbis kigeziensis, 190, 193. sperabilis, 190, 193. Plasmodium kocni, 414, 415. | Plasmodiuin precox, 240, 414, 415, 418. Platybunus pinetorum, 402. triangularis, 402. Platycercus icterotis, 408. Plectoptera, 366. Plesictis, 225. Plesiechinus, 448, 451. | 452. Plotus anhinga, 126. Podicipes cristatus, 72, 77, 79. Podoenemis expansa, 413. Podura armata, 8d. palustris, 93. Pceocephalus fuscicollis, 416. Polyzosteria cuprea, 358. limbata, 358. nove-zealandiea, 3d9. Porphyrio madagascariensis, 416. Porzana pusilla, 2. Pourtalesia, 496, Pratincola caprata, 2. Presbytis, 503. Prioptera sinuata, 871, 376. Pristes cuspidatus, 284. Procavia sp., 231. burtoni, 231. ruficeps, 231. Prosoplecta, 358, 363, 364, 367. bipunctata, 363, 368, 369, 371, 376. coccinella, 363, 3868, 369, 376. celophoroides, 369, 373, 376. gutticollis, 369, 372, 710. ligata, 368, 369, 371, 72. megaspila, 370. mimas, 369, 373, 376. nigra, 369, 372, 376. nigroplagiata, 369, 370, 371, 376. | XXV Prosoplecta nigrovariegala, 366. quadriplagiata, 369, 376. rufa, 369, 371, 376. semperi, 368, 369, 371, 376. trifaria, 368, 370, 372, 376. Prosthesima apricorum, 399. latretllii, 395. nigrita, 39D. petiverii, 399. prefica, 395. talpina, 399. Protanura krepelini, 119. Protocyamus, 452, 478, 494. Psammomys obesus, 228. Pseudachorutes anomalus, 81, 88, 119, 122. Pseudaspis cana, 413. Pseudocyphoderus, gen. nov., 89, 116, 121. annandalei, 81, 116, 121, 125. Pseudoglomeris, 363. Pseudoleistes guirahuro, 238, Pseudophyllodromia parilis, 362. Pseudosira, 99. indra, 81, 100, 101, 120, 123. Psittinus incertus, 233. Ptenothrix gracilicornis, 121. — gibbosa, 121. Ptenura, 97. Pteroglossus torquatus, 408. Pteroplatea micrura, 284. Ptilotis Jusca, 416. Ptyodactylus lobatus, 414. Putorius putorius, 234, Pycnonotus Jocosus, 415, | Pygaster, 443-449, 454, 457-466, 469-480, 484, 488-490, 493, 495. XXV1 Pygaster relictus, 452. reynest, 483. semisulcatus, 448, 451, 454, 455, 461, 468, 475, 482, 485, 488, — conoideus, 456. umbrella, 452, (Macropygus) noides, 455. (—) truncatus, 454. (Megapygus) macro- cyphus, 458. laga- (—) wmbrella, 454, 466, 468. Pygastrides, 452, 462. Pygurus blumenbachi, 474. Pyrina, 443, 444, 457, 458, 462, 464, 466, 469, 470, 480, 490, 493, desmoulinst, 489, Pyrrhulopsis taviunensis, 9, Python molurus, 412. reticulatus, 413. sebe, 411, 414. spilotes, 4138, Rallus aquaticus, Ramphastos dicolorus, 409. Rana catesbiana, 411. esculenta, 19, 410, 411. temporaria, 19. Rangifer tarandus, 232. Rhinoceros wnicornis, 30. Rhinolophus acrotis brachygnathus, 225. cornutus pumilus, 128. ferrum-equinum, 128. Rhinopithecus avunculus, 503. bieti, 503, 504. roxellane, 504. Rhinoptera javanica, 283, 284, 286, 288, 289. quadriloba, 279, Rhodites rose, 174. Rhynchobothrius, 280. 72, 78, 79. Rhynchonax andersont, 1380, 131. Rhytidoceros undulatus, 142. Robertus lividus, 397. Ruticilla rufiventris, 142. Salmo fario, 406. Saltator senilis, 409, Sarcophilus satanicus, 232. Scardafella sguamosa, 415. Sceloporus clarkii, 413. Sciurotamias davidianus consobrinus, 154. Sciurus castaneoventris hotet, 134. Scolopax rusticula, 71, 72, ao: Scops bakkamena, 2. leucotis, 416. Scopus, 126. Scotopelia bouvieri, 416, Scutella, 476. Segestria senoculata, 395. Segmentina eussoensis, 191, 193. kempt, 191, 193. Seira brahma, 81, 99, 120 123, Frigida, 81, 97, 123. sumatrana, 120. (Sira) annulicornis, 120. Semnopithecus ptleatus, 1. Sericulus melinus, 4. Serinus canicollis, 409. Setigera phanolepis, 120, 124. tarsata, \20. bon- ie d 81, 110, travancorica, 81, 108, | IAD), eae INDEX OF SCIENTIFIC NAMES. Sialia sialis, 409. Simia sp., 128. rhesus, 128. sylvana, 128. Sinella curviseta, 101. hofti, 102. montana, 81, 101, 128, 1 myrmecophila, 102. Singa albovittata, 899. hamata, 399. Sistrurus miliarius, 413. Sitala iredalet, 187, 193. Sitta castaneiventris, 2. Sitticus longipes, 402. Sminthurides appendiculatus, 81,117, 121, 125. Sminthurus, 117. Sorex bedfordie, 132. cylindricauda, 132. religiosa, 228. wardi, 182. — fumeolus, 132. Soriculus irene, 132, 138. macrurus, 132, 138. Spalax egyptiacus, 230. typhus, 230. Spatangus, 479, 493. Spermophila castanetventris, 409. minuta, 408. Sphezrium kigeziensis, 192, 193. Spheniscus humboldti, 61, 62. Sphenodon, 421. Spirocheta recurrentis, 410, Staurotypus treporcatus, 414, 415. Steatoda bipunctata, 397. Steatomys pratensis, 410, 411. Sternothzrus niger, 414. Stilesia, 208. hepatica, 207. sjostedti, 216. INDEX OF SCIENTIFIC NAMES. Stoparola melanops, 415. Strepera _ fuliginosa, 408. Strix Hamimea, 416. Styloctetor broccha, 398. (Hilaira) carli, 398. Succinea kempi, 189, 198. princet, 189, 193. Sula capensis, 1, Suricata suricatta, 407. Sus aper, 391, 392. attila, 391, 392, 393. celtica, 391, 392. europeéus, 391, 392. scrofa, 390, 591, 392. — beticus, 391, 392, 393. castilianus, 392. — scrofa, 391, 392. setosus, 391, 392. Synageles venator, 402. 291, Tadorna tadornoides, 416. Tenia marchali, 2\7. saginata, 195, 196, Teeniura melanospilos, 286. Tanagra episcopus, 409, 417, palmarum, 416. Tapinocephalus, 425, Tapinocy ba, affinis, 898. pallens, 398. Tapinopa longidens, 397. Tarbophis fallax, 412. Tarentola annularis, 414. mauritanica, 412, Tarentula accentuata, 401, aculeata, 401. andrenivora, 400. barbipes, 400. lessertii, 400, 404, 405. miniata, 400. Tarentula nemoralis, 400. pulverulenta, 400. trabalis, 400. Tayassu tajacu, 407. Tegenaria campestris, 396. derhamii, 390. domestica, 396. pusilla, 396. tridentina, 396. ‘Termes redemanni, 117. Testudo angulata, 411. Tetragnatha extensa, 398. Tetragonocephala, 284, Tetrao tetria, 72, 77, 79. Tetrarhynchus, 269. sp., 288, 292. balistidis, 286. evinaceus, 287, 350. minus, 279. pinne, 286. unionifactor, 268, 278, | 279-283, 347, 361. Teutana grossa, 397. Textor adlector, 415, Textrix denticulata, 306. Thanatus arenarius, 400. Sormicinus, 400. Thapsiella millestriata, 193: opposita, 186, 193. Tharrhaleus perdoni, 2, 285-290, 186, Theganopteryx, 865, 366, | 367. Thelotornis kirtlandi, 238, Theridion bigibbum, 396, 403. blackwallii, 397. nigro-punctatum, 397. nigro-variegatum, 397. pallens, 404. riparium, 390. sisyphium, 397. Thomisus onustus, 099, Thylacinus cynocephalus, 232. | XXVil Thyrsocera, 362. Thysanoteenia, 218. Tiarabothrium Javanicum, 284. Tigellinus saxicola, 397. Tinnunculus alaudarius, 416. Tomocerus, 115. vulgaris, 81, 91. (Macrotoma)monlanus, 120. Toxostoma bendirei, 3. Trachyeystis tredalei, 187, 193. Tragulus javanicus, 407. Trematopygus, 466. Trichoglossus nigrigularis, 416. Trichomonas, 411. Trichorypha, 106. Triconchus mobi, 397. Tringa minuta, 2. Trirachodon, 425, Trochosa leopardus, 400, terricola, 400. Tropidonotus fasciatus, 415. Trygon, 261. kuhli, 284. warnak, 284, walga, 283, 284. Trypanosoma avium, +10. Zewisi, 410. rotatorium, 410. 214, Tupinambis tequexin, 412. Turacus corythaix, 416. erythrolophus, 3. macrorhynchus, 416. persa, 416. Turdus migratorius, 408, mustelinus, 408. Tylocephalum, 262, 275, 287. dierama, 284, hkuhli, 284. ludificans, 408, 279-285, 282-293, 296, 347, 848, 352, 358. margaritifere, 274. XXVU1 Tylocephalum minus, 279, 285, 286, 292, 298, 352. pingue, 279. warnak, 284, 358. (Letragonocephalum) abtobatidis, 283. (—) trygonis, 283. Tympanistria bicolor, 415. 282, 283, 288, 290, 337, 347, Urobrachya albonotata, 408. Urocissa occipitalis, 410. Uropsilus, 127. soricipes, 129, USI. Urotrichus, 130, 131. Ursus isabellinus, 498. 130, Varanus bengatensis, 412. niloticus, 414. varius, 412. Vidua paradisea, 417. Vipera ammodytes, 414. russelli, 414. Vitrina compacta, 184, 193. Vivipara rubicunda kisumiensis, 191, 198. Vulpes hengalensis, 252. lagopus, 55, 238. zerda, 225. Withius, 388. Xenylla brevicauda, 895. grisea, 809. humicola, 85. maritima, 85. mitida, 85. obscura, 81, 84, 119, Xiphidiopictus percussus, 232. Xysticus bifasciatus, 399. cristatus, 399. erraticus, 399. INDEX OF SCIENTIFIC NAMES. Xysticus gallicus, 399. glacialis, 399. kochit, 399. lanio, 399. lateralis, 399. luctator, 399. pini, 399. Zamenis constrictor, 413. dahli, 414. jlagelliformis, 413. gemonensis, 414. hippocrepis, 412. mucosa, 413. Zilla montana, 398. stroemiti, 398. «z-notata, 398. Zingis kempt, 185, 193. papyracea, 185, 193. planispira, 185, 195. Zodarion gallicum, 396. Zora maculata, 396. Zosterops virens, 233. INDEX OF PEE UST RAPIONS: Aceipiter nisus, Pls. II., IV., p. 63. Africarion kempi, Pl, XXX1. p. 183. —— microgranulata, Pl. XXXI. p. 183. — microstriata, Pl, XXXT.sp. 183. Alea keniana, Pl. XXXI. p. 183. Anaplecta decipiens, Fig. 44, p. 365. Ancylus kempi. Pl, XXXT. p. 183. Anisolemnia distaura, Pl. XUVIILI. p. 358. Anorthopygus, Figs. 55, 56, 58, 59, pp. 459, 464, 473, 479. Aptenodytes pennanti, Pl. I. p. 60. Ardea cinerea, Pl. XIII. p. 125. Assimania aurifera, Pl. XXXT. p. 183. Chelifer latreillii, Rigs. 47, 50, pp. 380, 386. Chorisoneura teniata, Fig. 43, p. 365. Chrotogale owstoni, Figs.61-63, pp. 500-— 502. Circus eruginosus, Pl. ITT. p. 63. —— ctneraceus, P|. III, p. 63. —— cyaneus, Pls. III.-V., p. 63. Clypeaster, Fig. 59, p. 479. Celophora formosa, Pl. XLVITI. p. 358, Coenholectypus, Fig. 59, p. 479, Conoclypeus, Fig. 57, p. 469. | Conulus, Figs. 55-59, pp. 459, 464, Asticopsis franklinii, Pls. XIV., XV., | XXV., XXVI., p. 144. serratus, Pls. XXVL., p. 144. Bacillus rossii, Pls. XXVIII-XXX., p. L72. Blawieria exsilium, Pl. XXX. p. 183. Blood - parasites. Pls. XLIX.-LYV., p. 106. Caricella . 126. Cephilobothrium, Fig. 84, p. 285. aétobatides, Pl. XLVII. p. 260. Cherips intermedius, Pls. XXIV., XAXVIL., p. 144. —— quinquecarinatus, Pls. XXIIL., XXIV., XXVIL., p. 144. fenuimanus, Pls, XXII., XXVIL., . 144. Chelier cyrneus, Figs. 48-50, pp. 882, 384 386. cunningtoni, Pl. LVIII. 469, 478, 479. albogaterus, Wig. 54, p. 455. | Cremastocephalus indicus, Pl. IX. p. 80. —— kershawi, Pls. X1X., XX., p. 144. | XVI-XVIIL., | montana, Pl, 1X. p. 80. Cygnus bewicki, Pl. TIT. p. 63. Cynognathus, Fig, 53, p. 424, | Diagram of the adoral surface in some Holectypoida, Fig. 54, p. 455. of the perignathic girdles in some Holectypoida, Fig. 55, p. 459. showing some characteristic plates of the ambulacra in some Holecty- poida. Figs. 56, 57, pp. 469, 473. showing the shape and position of the periproct in some Holectypoida, Fig. 56, p. 464. Dicranocentroides VITI.-X., p. 80. Dicynodon, Fig. 58, p. 424. Discoidea, Figs. 55-59, pp. 459, 464, 469, 473, 479. Jusciculatus, Pls, | ——— eylindrica, Fig. 54, p. 455. Elephantulus rupestris, Fig. 17, p. 143. Ennea microstriata, Pl. XXX. p. 185, XXX Entomobrya crassa, Pl. VII. p. 80. kal, Pls. VII., VIII, p. 80. Hussoia tnopina, Pl. XXXII. p. 1838. Falco peregrinus, Pl. IIT. p. 63. subbuteo, Pl. III. p. 63. —- tinnunculus, Pl. IL. p. 63. | Galeropygus, Figs. 57, 58, pp. 469, | 473. agariciformis, Fig. 54, p. 455. Galictis, Fig. 31, p. 222. Gazella rufifrons haslert, Figs. 2, 3, pp. 5, 6. Hemoproteus danilewskyt, Pl. LIT. . 406. Hemithyrsocera sp., Fig. 42, p. 364. Heteromuricus ceroifer, Pls. VIII., 1X., p- 80. Holectypus depressus, Figs, 54, 56, 58, pp. 455, 464, 473. hemispherieus, Figs, pp. 464, 473. Homorus iredalei, Pl, XXX1I, p, 183. 56, 58, Idiomerus pallidus, Pl. IX. p, 80; Fig. 15, p. 114. Isotoma nigropunctata, P\. VIL. p. 80, siva, Pls. VI., VIL., p. 80. Isotomurus palustris, Pls. VI,, VIL, | p: 80. | Kaliella consobrina, Pl. XXXI. p, 183, depauperata, Pl. XXXI. p. 183. tredalet, Pl. XXXI. p. 183. — kigeziensis, Pl, XXX]. p. 183. Lagopus scoticus, Pl. 111. p. 63, Larus minutus, Pl. ILL. p. 63. Leis duntopi, Pl. XLVILII. p. 388. Leucochiloides chanlerensis, Pl. XXX. p. 183. gaziensis, Pl. XXXI. p. 183, wredalei, Pl. XX XI. p. 183, soror, Pl. XXXTI. p. 183. LTimnea kempi, P\. XXXII. p. 183, LTimnocaridina parvula, Pls. LiX., LX., p. 426, spinipes, Pl. LVIL. p. 426. Macropygus, Fig. 56, p. 464. Macroscelides proboscideus, p. 143. Map of Australia, showing distribution of Orayfishes. Fig. 18, p. 149. of Oriental Region, showing localities at which Collembola were | obtained. Fig. 14, p. 82. | Margaritifera margaritifera, Fig. 38. | p. all. Fic. 16, | | Plans showing horse-trough, ete. _ Podicipes cristatus, Pls. IIT., 1V., INDEX OF ILLUSTRATIONS. Margaritifera maxima, Figs. 36, 37, pp. 805, 306. —— vulgaris, Pls. XXXIII-XXXvV., XXXVIT.-XUL., p. 260; Fig. 35, p. 302. Megapyga eximia, Pl. XLVITL. p. 358. Megapygus, Figs. 56, 57, pp. 464, 469. Mellivora, Figs. 31, 32, pp. 222, 223. Melyroidea magnifica, Pl. XUNIIT. p- 358. —— mimetica, Pl. XLVIII. p. 358; Fig. 46, p. 874. Mytilus edulis, Pl. XXXTV. p, 260. Natalina permembranacea, Pl. XXXI. p- 188. Neanura corallina, Pl. VII. p. 80. intermedia, Pls. VI,, VIL., p- 80. pudibunda, Pl. V1. p. 80. Oides biplagiata, Pl. XLVIII. p. 358. Otiditenia eupodotidis, F igs. 19-380, pp. 194, 197-202, 204, 206, 208, 212, 215. Oudenodon holbei, Pl, LVI. p. 419. | Paracheraps _bicarinatus, Pls. XXT., XXVIL, p. 144. Paronella borneri, Pls. X,, XI1., p. 80. —— gracilis, P|. XI. p. 80. —— insignis, Pi. XI. p. 80. ——-phanolepis, Pls. X,, XI, p. 80, = travancorica, Pls. 1X., X., p. §0. Pearls. Pls. XXXV.-XLVL., p. 160; - Figs, 38, 39-41, pp. 277, 318, 819, 340. Phylogenetie table of the Holectyyoida and their allies. Fig. 60, p. 498. Pileus, Fig, 57, p. 469. | Planorbis kigeziensis, Pl, XXXII. p- 183. sperabilis, Pl. XXXII. p. 183. used for homing experiments with Am- phibia, Figs. 4, 5, pp. 12, 15. Plasmodium precox, Pl, LILI, p, 406, ip. 65, Prioptera sinuata, Pl, XLVIIL. p| 358. Prosoplecta bipunciata, P1, AN. Il. p- 308. coccinella, Pl. XLVIIL, p. 38. celophoroides, P\. XLVITL. }, 358, —— guiticollis, Pl. XLVIIL. p. 8, mimas, Pl. XLVITT. p. 858, nigra, Pl. XLVILIL. p. 358. —— nigroplagiata, P\, XLVIII, }, 358. —— nigrovariegata, Fig, 45, p, a quadriplagiata, Pl. XLV IT p. 358. INDEX OF ILLUSTRATIONS. Prosoplecta rufa, Pl. XLVILII. p. 358. senperi, Pl. XLVILI. p. 358. trifaria, Pl, XLVIIL. p. 358, Pseudachorutes anomalus, Pl. VI. p. 80. Pseudosira indra, Pls. VII., VIIL., p. 80. Pygaster, Figs. 55-59, pp. 459, 464, 469, 473, 479. -—— semisulcatus, Fig. 54, p. 455. (Macropygus) laganoides, Fig. 54, 455. (Megapygus), Fig. 59, p. 479, Pyrina, Fig. 57, p. 469. Rallus aquaticus, Pl, ILI, p. 63, Scolopax rusticula, P\. III. p. 68. Segmentina eussoensis, Pl. XXXII, p. 183. kempi, Pl. XXXII. p. 183. Seira brahma, Pl. VIUI. p, 80. frigida, Pl. VIII, p, 80. Sericulus melinus, Fig. 1, p. 4. Sinella montana, Pls. VILL., [X., p, 80, Sitala iredalei, Pl. XXXI. p. 183. Spatangus, Fig. 59, p. 479. Spherium kigeziensis, Pl. XXXI. p, 183. XXX1 Suceinea kempi, Pl, XXXIT. p. 183. princei, Pl. XXXII. p. 183. Tarentula lessertii, Fig. 52, p. 405. Tetrao tetrix, Pl. III. p. 63. Thapsiella millestriata, P}. p. 183. opposita, Pl. XX XIT. p. 185. Theridion bigibbum, Fig. 51, p. 403. Trachycystis iredalei, Pl, XXXII, p. 183. Tylocephalum, Big. 34, p. 285. ludificans, Pls. XXXIII., XLVI, XLVII., p. 260. minus, Pl. XX XIII. p. 260, uarnak, Pl, XLVIL. p, 260, XXXII. Vitrina compacta, P|. XXXII. p. 185. Vivipara rubicunda kisumiensis, Pl, XXXII. p. 183. Vulpes lagopus, Figs, 6-13, pp. 56-59. Xenylla obscura, Pl. VI. p, 80. Zingis kempi, Pl. XXXIT. p. 183. papyracea, Pl, XXXII. p. 185. -—— planispira, Pl, XXXII. p, 183, PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET, hip aie Wea an ens a Late ee hare fe eee PROCEEDINGS OF TIE GENERAL MEETINGS FOR SCIENTIFIC BUSINESS OF TILE ZOOLOGICAL SOCIETY OF LONDON. EXHIBITIONS AND NOTICES. October 24, 1911. Sir Jonun Rose Braprorp, K.C.M.G., M.D., F,R.S., Vice-President, in the Chair, Tue Secrerary read the following report on the Additions that had been made to the Society’s Menagerie during the months of June, July, August, and September, 1911 :— JUNE. The registered additions to the Society’s Menagerie during the month of June were 602 in number. Of these 164 were acquired by presentation, 70 by purchase, 265 were received on deposit, 32 in exchange, and 7] were born in the Gardens. The number of departures during the same period, by death and removals, was 328. Amongst the additions special attention may be directed to :— A collection of Mammals, Birds, and Reptiles from Africa (chiefly South), presented to H.M, King George by various donors, and deposited in the Gardens by His Majesty on June 2nd, including 2 Eastern White Pelicans (Pelecanus roseus), 3 Cape Gannets (Sula capensis), 1 Scarce Duck (Anas sparsa), | Robust Lizard (Gerrhosaurus validus), and | Black-lined Lizard (Gerrho- saurus nigro-lineatus), all new to the Collection. 2 Capped Langurs (Semmnopithecus pileatus) from the Himalayas, new to the Collection, purchased on June 6th. 1 Hoffmann’s Two-toed Sloth (Chalepus hoffmanni), from Brazil, purchased on June 17th. Proc, Zoon, Soc, —1912, No. I. | 2 THE SECRETARY ON ADDITIONS TO THE MENAGERIE. A collection of rare Indian Birds presented by E. J. Brook, Esq., F.Z.S., on June 6th and 19th, including 2 Grey-headed Ouzels (Merula castanea), 2 Pied Bush-Chats (Pratincola caprata), 1 Ruby-throat (Calliope camtschatkensis), 1 HKlegant Bunting (Hmberiza elegans), 1 Jerdon’s Accentor (Tharrhaleus jerdoni), 2 Yellow-cheeked Tits (J/achlolophus xanthogenys), 2 Chestnut- bellied Nuthatches (Sitta castaneiventris), 1 Black-headed Wagtail (Motacilla feldeggi), 1 Blue-throated Flycatcher (Cyornis rube- culoides), 2 Sikkim Siskins (Chrysomitris tibetana), 1 Collared Scops Owl (Scops bakkamena), and a pair of Blood Pheasants (Lthagenes cruentus), all new to the Collection. 2 Peale’s Parrot-Finches (Hrythrura pealei), from the Fiji Islands, new to the Collection, deposited on June 14th. 2 Taviuni Parrakeets (Pyrrhalopsis taviunensis), from Taviuni, Fiji Islands, new to the Collection, presented by Dr. P. H. Bahr, FE.Z.S., on June 6th. 1 Pigmy Crake (Porzana pusilla), and 3 Little Stints (7ringa minuta), from India, new to the Collection, deposited on June 6th. 2 Hooded Cranes (Grus monachus), from Japan, purchased on June 6th. JULY. The registered additions to the Society’s Menagerie during the month of July were 444 in number. Of these 174 were acquired by presentation, 62 by purchase, 56 were received on deposit, 12 in exchange, and 140 were born in the Gardens. The number of departures during the same period, by death and removals, was 278. Amongst the additions special attention may be directed to :— 1 African Cheetah (Cynelurus jubatus), from Berbera, Somali- land, purchased on July 22nd. 3 Cape Sea-Lions (Otaria pusilla), from South Africa, received from Dr. Louis Péringuey, F.Z.8., for H.M. THe Kine’s African Collection, on July 29th. 1 Tibetan Wild Ass or Kiang (Zquus kiang), 3, born in the Menagerie on July 13th. 7 White-rumped Lories (Hos fuscata), from New Guinea, new to the Collection, | purchased and 6 deposited on July 13th. 1 Wolf-Snake (Coluber vulpinus), from North America, new to the Collection, received in exchange on July 8th. A. Collection of rare Reptiles and Batrachians from Trinidad, presented by Dr. Lewis Henry Gough on July 11th, including 18 Warty Tree-Frogs (Tyla venulosa), 1 Daudin’s Tree-Frog (Hyla rubra), and 16 Tree-Frogs (Hyla goughi), all new to the Collection. AvGusT. The registered additions to the Society’s Menagerie during the month of August. were 229 in number. Of these 85 were acquired by presentation, 21 by purchase, 8 were received on deposit, 62 in exchange, and 53 were born in the Gardens, THE SECRETARY ON ADDITIONS TO THE MENAGERIE, 3 The number of departures during the same period, by death and removals, was 244. Amongst the additions special attention may be directed to :— 1 Red-faced Spider-Monkey (Ateles paniscus) and 1 Brown Capuchin (Cebus fatuellus), from British Guiana, presented by Messrs. John Reed and W. A. Boyd on August 3rd. 1 Clouded Tiger (Felis nebulosa), from British North Borneo, presented by Almeric Paget, Esq., F.Z.S., on August 29th, 1 Ocelot (Felis pardalis), from Para, presented by F, J. Weldon Taylor, Esq., on August 16th. 1 Lesser Superb Bird-of-Paradise (Lopharhina minor), from S.E. New Guinea, new to the Collection, presented by E. J. Brook, Ksq., F.Z.S., on August 12th. 1 Red-crested Touracou (Z'uracus erythrolophus), from Angola, deposited on August 31st. A Collection of American Birds, including 2 Bendire Thrashers (Toxostoma bendirer), 4 Gila Woodpeckers (Jelanerpes uropygialis), and 4 Douglas’ Quails (Lophortyx douglasi), all new to the Collection, received in exchange on August 3rd. 2 Broad-tailed Babblers (Crateropus platycercus), from Gambia, new to the Collection, presented by Dr. E. Hopkinson, D.S,O., F.Z.S., on August 7th. 1 Striped Gonatode (Gonatodes vittatus), from Trinidad, new to the Collection, presented by Dr. L. H. Gough on August 31st, SEPTEMBER. The registered additions to the Society’s Menagerie during the month of September were 361 in number, Of these 137 were acquired by presentation, 39 by purchase, 39 were received on deposit, 125 in exchange, and 21 were born in the Gardens, The number of departures during the same period, by death and removals, was 254. Amongst the additions special attention may be directed to :— 1 Persian Gazelle (Gazella subgutturosa), from Arabia, presented by Rear-Admiral Sir E. J. W. Slade, K.C.I.E,, M.V.O., R.N., F.Z.S., on September 7th. 2 Tamaulipas Tawny Thrushes (Merula tamaulipensis), 2 Derby Tyrants (Pitangus derbianus), 1 Giraud Tyrant (Jyiozetetes similis), 4 Black-breasted Colins (Colinus pectoralis), fram Mexico ; 4 American Barn-Owls (Asio accipitrinus), from North America, 1 Hodgson’s Pipit (Anthus rosaceus), 1 Indian Tree-Pipit (Anthus maculatus), 2 Grey-headed Buntings (Hmberiza fucata), 1 Pine- Bunting (Zmberiza leucocephala), and | Hume's Short-toed Lark (Calandrella acutirostris), from India, all new to the Collection, and received in exchange on September 27th. 2 Formosan Pheasants (Phasianus formosanus), from Formosa, new to the Collection, presented by W. H. St. Quintin, Esq., F.Z.S., on September 12th. |* 4 MR. D. SETH-SMITH ON A NESTLING REGENT-BIRD. Mr. James DunsBar-Brunton sent for exhibition two skins and a mounted skull, with horns, of Bushbuck shot by him in North- Kast Rhodesia. . W. B. Corron, of the Indian Civil Service, exhibited a number of heads and horns of various species of Gazelles which he had obtained in the Eastern Sudan, and gave a brief account of their habits and distribution. The specimens included Gazella isabella, from the hills behind Suakin and the route from Sinkat to Kassala, and eleven specimens, of which he under- stood nine to be Gazella tilonura and two to be Gazella rufifrons, from the Atbara, Settit, and Rahad. Mr. Cotton mentioned that some sportsmen believed isabella to be identical with dorcas, and advanced a decided opinion that tilonura was merely a local form of rufifrons. This opinion was fortified by consideration of the extreme variation of type in the specimens exhibited, of which all but one had come from the same locality, namely the Atbara and Settit. Mr. D. Serx-Smiru, F.Z.S., Curator of Birds, exhibited a spirit-specimen of a nestling Australian Regent-Bird (Sericulus melinus) (text-fig. 1), which had been hatched in the aviary of Mr. Reginald Phillipps, of 26 Cromwell Grove, West Kensington, during the past summer, The male parent of this bird was also bred in the same aviary in 1906, and is the only specimen of this fine Bower-Bird ever bred and reared to maturity in captivity. Text-fig, | Sericulus melinus, ten days old. Two young birds were hatched this year (1911), but succumbed to the effect of a thunderstorm in July, when about ten days old. The nestling is chiefly remarkable for the length and thickness of fluffy down on the feather tracts, especially upon the head. ~ MR. R. I, POCOCK ON A NEW RED-FRONTED GAZELLE, a) The exhibitor remarked that thanks to Mr. Phillipps’ generosity, the parents of this young bird now formed part of the Society’s collection, and were amongst the rarest of the exhibits, since at the present time they were probably the only living examples of this fine species in captivity. Mr. R. I. Pocock, F.R.S., F.L.S., F.Z.S., Superintendent of the Gardens, exhibited two photographs (text-figs. 2 & 3) of a male specimen of Red-fronted Gazelle (Gazella rufifrons) which came from Kano in Northern Nigeria, and was presented to the Society in 1908 by Col. Julian Hasler. This specimen apparently represented an undescribed race which he proposed to name and to diagnose as follows :— GAZELLA RUFIFRONS HASLERI.* Abstract P. Z. S. No. 100, p. 47 (Oct. 31st). Back ochre-fawn in colour with a well-defined paler area between the richer tint of the dorsal area and the infero-lateral Text-fig. 2. Side view of Red-fronted Gazelle, Gazella rufifrons hasleri. black stripe. This stripe, as in the typical form from Senegambia, with a narrow border of fawn below. Basal inch of the tail the same tint as the back, the rest black. Only a faintly defined dark * The complete account of this new subspecies appears here, but since the name and a preliminary diagnosis were published in the‘ Abstract,’ it is distinguished by being underlined,—Eprror, 6 MR. J. LEWIS BONHOTE ON mark bordering the white of the back of the thighs. Forehead a darker and richer colour than the neck and cheeks, a few white hairs between the horns. The whole of the upper side of the nose from the preorbital glands to the nostrils snow-white like the chin. The glands themselves and the area round the eye creamy white or very pale fawn. No black on the legs or feet ; the glandular tafts below the knees present as in all the examples of G. rufifrons that had been exhibited in the Gardens. Text-fig. 3. Head of Red-fronted Gazelle, Gazella rufifrons hasleri. This Gazelle differed from all previously described specimens of G. rufifrons in the whiteness of the upper side of the nose. Mr. J. Lewis Bonnors, M.A., F.L.S., F.Z.8., exhibited living specimens of Rats (us rattus) which he had bred in the course of his experiments and which showed the “ waltzing” character well known in a variety of the domestic mouse, but which had not hitherto been recorded in rats. The original stock from which these rats had been bred was caught wild at Giza near Cairo (see P. Z.8. 1910, p. 664), and the experiments were being conducted to study heredity in two varieties found in a wild state, namely, Mus rattus teclorwm with pure white underparts, and Mus rattus alewandrinus, im which the hairs of the underparts were entirely slate-eoloured or had slate-coloured bases. ‘The experiments were also being conducted to test the inheritance of a fawn-coloured individual which had appeared asa “sport” in the first generation from pure wild parents (P. Z.8. 1910, p. 638). With regard to the heredity of the two normal varieties the white-bellied form (JZ. r. tectorum) was found to be apparently a simple Mendelian dominant to the dark-bellied form (J/. rv. alewandrinus), the WALTZING RATS. 7 dark-bellied ones always breeding true and the heterozygous light-bellied ones giving a proportion of pure alexandrinus. This entirely bore out the suggestion put forward by Mr. Bonhote in a former paper (loc. cit.) that the main varieties (or sub-groups as he had called them) of Mus rattus were true Mendelian mutations. It would thus be understood how forms (which were at present considered as closely allied species) and which differed only in small but constant characters, were able to exist side by side under practically identical conditions without those characters becoming blended or one of them being lost, as would be bound to occur if natural selection were the only active force in evolution. With regard to the heredity of the fawn—the original specimen, a male, which showed the characteristic white underparts of J/. teclorum (its parents), was mated to an alewandrinus 9 , and the resulting F, generation, some thirty in number, were all typical white-bellied tectorwm. Five pairs of these were mated and gave in the F, generation :— 17 Tectorum, 5 Alexandrinus, 7 Fawn 'T., 1 Fawn A. the expectation being 18 A 6 PS 6 4 2 a! In addition, there were three individuals that died before it could be determined whether they were alexandrinus or tectorum, but they were not Fawn, as these could be distinguished at birth. The fawn colour, which was probably due to the absence of black, was, therefore, recessive to the normal grey colouring but might occur in either of the normal forms. Thus a rat having an absence of black and presence of the Alexandrine (slaty underparts) character was whitish fawn in colour, since the number of hairs which should contain black was much greater and in the absence of the black factor these hairs were colourless. It might be noticed that in young Fawn Rats the eye was ruby coloured, as in the case of the Cinnamon Canary, becoming quite dark as maturity was reached. The “waltzing” rats, of which altogether four had been produced, all appeared in the F, generation, but were not all from the same parents. Of the matings for the F, generation only one (daughter x father) produced sound young. Apart from the “‘ waltzing ” character, three individuals were born blind, and in two of these cases the eyes were undeveloped and the optic nerve absent, and in addition many of the young that were reared were so weakly that they had to be killed, and others died before being weaned. From certain causes, therefore, which are not very clear, partly due to inbreeding, partly probably to environment, and partly pos- sibly to their breeding at too early an age (6 months), a degenerate and defective generation was produced, and one of the results was to bring about in certain individuals a character (‘ waltz- ing”), which in a nearly allied species was shown * to have a Mendelian inheritance. * Darbishire, ‘Biometrika,’ i. pp. 101, 165, 282 (1902), ibid. iii. p. 1 (1903) ; G. von Guaita, Ber. Naturg. Ges. Freiburg, x., x1. (1898) (1900). 8 MR. B. F. CUMMINGS ON PAPERS. 1. Distant Orientation in Amphibia. By Bruce F. Commines *. [ Received September 1, 1911: Read October 24, 1911.) (Text-figures 4 & 5.) INTRODUCTION. The observations and experiments detailed below were made in North Devonshire during the course of the last two years. The Amphibia chiefly used were two species of Newts. The British Newts have a peculiar geographical distribution in these Islands, and, living in the north of Devon, I was fortunate in being able to obtain large quantities of two species, Molge cristata Laur., and Molge palmata Schneid. It has long been the custom of field naturalists, year after year with all the precision of Gilbert White of Selborne, to note the date of the first return of Frogs and Efts to their breeding-ponds as indicative of the return of spring. It occurred to me to enquire how the Amphibia find the water again after having left it in the autumn of the preceding year. Nothing appears to be known of this subject, although the problem of these amphibian migrations is a simple one compared with that of the migrations of birds, which has attracted, and still is attracting, so much attention from the students of animal life. No one has shown how the Amphibia find the water, and it is not definitely known whether the Amphibia return to the same piece of water each spring, nor whether every animal or only a lucky small percentage finds water as the breeding season comes round, nor precisely how extensive their perambulations on land may be during the autumn months before hibernation sets in. Many larval Newts, and a few adult Newts of Molge palmata remain in the water hibernating at the bottom of the pond. But these are exceptional. The majority of our Amphibia do leave the water, and large numbers annually find their way back to it in the following spring. The Newt is essentially a nocturnal animal, and a visit to a newt-pond with a lantern after dark, whether in spring or autumn, is sufficient to show that night is the time when the migrations are carried on. The answer te the question how these amphibian migrations are performed must involve points of importance to amphibian psychology and, when elucidated, the subject will form an interesting chapter in their naturai history. The literature is scant and vague. G. J. Romanes t thought that Frogs had a distinct idea of locality. He based this idea on the cases reported to him by some of his correspondents, where Frogs, removed a distance of 200 or 300 * Communicated by T. A. Cowarp, F.Z.S. + G. J. Roimanes, ‘ Animal Intelligence,’ p. 254. AMPHIBIAN MIGRATION, 9 yards from their habitual haunts, returned to them again and again. He also expressed the opinion that Frogs were able to perceive moisture from a great distance, and he quotes Warden who in “ An Account of the United States,” vol. ii. p. 9, says that a pond containing some Frogs having dried up, the animals “made straight for” the nearest water, though it was eight kilometres away. CoMPENSATORY HBAD-MOVEMENTS. In all experiments with the Amphibia it is necessary to beware of error through compensatory head-movements, which, if neglected, give « false complexion to the results. No mention of them is made by Romanes’ correspondents and no details of the experi- ments are given. It isastonishing to find how persistently Newts will return and immediately re-enter their pond, after they have been removed from it to some considerable distance. Even when placed heading directly away from the water, they turn round and walk towards the water, as if endowed with a quite uncanny knowledge of the geographical features of the neighbourhood of their breeding-pond. The explanation partly lies in the head- movements contrary to the movement of rotation, set up by the motion of the experimenter’s hand as he turns the Newt round to face away from the water. The Newt mechanically responds by turning round, with the head towards the water. These move- ments are very pronounced in the Newt on account of its linear shape. A Newt, on a rotating disc which is being moved back- wards and forwards through an angle of 180°, responds correctly if the motion is slow, 7.e., it turns its head regularly in the opposite direction to the backward and forward movements of the dise. If the motion of the dise be fast, it overtakes the slow head-movements of the Newt, and the Newt hecomes confused and escapes from the predicament by lowering its chin so as to place it in contact with the moving disc. No response is then given. Continuous rotation in one direction produces no very marked external signs of giddiness. But in the Common Toad (Bufo vulgaris) these signs are marked. While the disc is moving the head is motionless. As soon as it stops, the Toad begins to crawl round in circles moving in the direction the dise had been moving. One of these animals, after rotation of one minute, in this way crawled through four circles! If a Newt be rotated through 90° in a trough with perpendicular walls two inches high, I have seen it turn in response to the rotation and climb over the side. GEOTAXIS. This subject must also be taken into consideration, It must be borne in mind that the ground around most ponds is sloping. Most fresh water lies at the bottom of hollows or at the foot of slopes. Newts are positively geotactic. They preferred to walk 10. MR. B. F. CUMMINGS ON downhill when I tested them in the spring, but in the autumn this preference changed and they went up. In work with an inclined plane, Molge cristata was chiefly used. The Newts were kept in water in large earthenware pans under similar conditions so far as possible. The observations were made in the early morning or at night, always in subdued light. The plane was of wood and measured 125 centimetres by 82 centi- metres 5 millimetres. A line was drawn transversely across the plane, and each Newt on removal from the pan was allowed to crawl on a level surface adjoining until manceuvred with the finger into the right direction, when it was swiftly lifted on to the incline and left in a horizontal position. In this way I cut out errors arising from compensatory head-movements. An interval of ten minutes was allowed each animal before being tried again. This prevented errors arising from simple habit formation, which in the Newt is rapid. Table I. shows the results of experiments performed in the spring when the Newts, used singly, walked downhill in 80 per cent. of the tests. Similar results were obtained by using Newts in series; twenty Newts were used. The number of positive re- sponses was in this way reduced to 67 per cent., which perhaps is nearer the truth. Table II. was obtained in the autumn when the Newts were endeavouring to leave the water for winter quarters. The Newts were then negative and walked uphill 72 per cent. of the times. In this table the Newts were used in series, the first row being worked by twenty Palmates and the rest by twenty Crested. TART E neice Incline. Eoeion at | Down. Up. | Neutral.) Total. 1 16° Horizontal. 12 (0) (0) 12 1 16° | Facing Up. 1 0 0 1 iL 122 Horizontal. 11 1 0 12 2 10° a 10 1 1 12 2 10° | Facing Up. 2 il 0 3 3 10° Horizontal. 12 2 1 15 3 10° o 6 1 0 7 4 5° : 10 1 3 14 4 5° | Facing Up. 3 0) 0 3 4, Ba Horizontal. i 3 3 13 Motalsieees. 74 10 8 92 AMPHIBIAN MIGRATION. 11 TABLE IT, Incline.| Position. Down. Up. | Neutral. Total. | 8° Horizontal. 4 19 1 24 g° _ 8 33 0 41 8° FS 13 26 4 43 Motalsiisec- 25 78 5 108 The real cause of the Newts normally walking downhill may lie in the weakness of the limbs. Yet, from a few observations made on the strong-limbed Toad placed horizontally on an incline, IT am induced to think that it also usually goes down, if given the choice. But, as in the case of the Newt, the cause of this’ behaviour of the Toad when placed horizontally on an incline receives a simple mechanical explanation. The kick given by the hind leg, which is higher up the incline than the other, would naturally tend at the moment of the hop to turn the animal down- wards. The Toad always hops downhill, but it crawls and rarely hops wp a gradient. On an incline of 12° one of my Toads would begin hopping downhill. If it was then teased on one side so as to send it up, the Toad would endeavour to continue hopping uphill, but when once facing up, the gait very quickly changed to a crawl. It may be observed that when endeavouring to hop up, the hind limbs cannot be brought up under the body from a state of extension unless they scrape the ground. After they have once scraped the ground in this way, the Toad ceases to attempt to hop, but crawls. It would appear, therefore, antecedently probable that in the spring, at the time of their greatest activity, the general tendency of the Toad also would be downhill towards water, rather than up. One more observation is worth recording. Some Newts, when placed on a level surface or on only a slight incline, would never start off straight in any direction. They always turned, and some of their turns were very elaborate. They would meander about the centre of the board around and up and down, before setting out in any particular direction. When once started, however, they went ahead. I regard this elaborate turning merely as a complex withdrawing response. Similar behaviour has been noted in the Crayfish *. All those Newts which winter on the slopes around the pond could, by their geotactic responses, easily find their way back to the water in spring. They would simply walk downhill. * J. Carlton Bell, “Reaetions of the Crayfish,’ Harvard Psychological Studies, Vol. 11. 1906, p. 615. 12 MR, B. F. CUMMINGS ON Homine Experiments, 1910. The first step was to find a pond suitable for experimental purposes, which was not easy in this neighbourhood where ponds are not common. Eventually I found a pond, which though not by any means the. best possible, yet fulfilled sufticiently the required conditions. It was conveniently near home, it contained a good number of Palmate Newts, and was small enough to admit of a thorough dredging. Text-fig. 4 represents the general nature of the surroundings. The sides of the pond were bricked up, and there was a thick sediment of mud at the bottom. The three sides A, B, C, rose perpendicular from the water for a foot, while at the fourth and remaining side the water was level with the edge. The depth was 18 inches on an average, but it varied of course at different states of the weather and at different periods of the spring season. The area of the surface-water exposed was 4 sq. metres 60 sq. decimetres. Yext-fig. 4. ROAD TALL [HEDGE cc. GENTLE INCLINE QB -- GATE average Sub-fam. EnromoBry1n& Schiff. Genus Isoromurus Born. Isotomurus Borner, ‘* Neue altw. Collem., nebst Bemerk. z. Syst. der Isotom. und Entomob.,” Sitz. Gesell. naturf. Freunde zu Berlin, 1903, p. 129. *JIsoromurus PALusTRIS Miill. (Pl. VI. fig. 15; Pl. VII. gs. 21, 22.) rSyn. 1776. Podura palustris Miiller, Zool. Dan. Prodr.. Havnie, p. 184. 1873. /sotoma palustris Lubbock, Monogr. Coll. and = Thys, p- 169. r HHead.—The eyes eight in number on each side (fig. 22). Antenne.—A little longer than the thorax, the joints related proportionately in length as 4: 8:9: 9 (in one example they were related as 3:6:7:8). Trunk.—Clothed with plumose hairs. The third abdominal segment a little longer than the fourth. Furcula.—As long as, or a little longer than the antenne: reaching to the ventral tube. The dentes approximately twice the length of the manuhriwm. Coloration.—Ochre-yellow, either with or without a few small irregular scattered black markings on the dorsal aspect, which coalesce in some specimens to form blotches. The antenne and furcula paler; the antennz in two examples tinged with purple. Length 2 mm. Ten specimens, taken on the surface of water at Calcutta t (Undian Museum Collector, Sept. 1st, 1908, and Sept. 22nd, 1909). No. = Indian Museum Coll. The specimens agree in all essential details of structure with European forms of the species. fi t I. palustris has been previously recorded from the Orientai region by Bérner, from Java. 94 PROF. A. D. IMMS ON Genus Lepipocyrrus Bourlet. Lepidocyrtus Bourlet, Mém. s. les Podurelles, 1839, p. 15. Lepidocyrtus Borner, ‘“ Das System der Coll.,” Mitt. Naturhist. Mus. Hamburg, 1906, xxii. pp. 164 and 174. [Including Pseudosinella Schiff. arn Acanthurella Born. | LEPIDOCYRTUS ROBUSTUS, sp. n. Segmentum abdominale quartum, thoracem, et segmentum abdominale primum longitudine equans. Unguiculus superior dentibus duobus parvis armatus ; unguiculus inferior lanceolatus, inermis. Long. 3°6 mn. Antenne.—Three times longer than the head, the joints related to one another in length as 2:3:3: 4. Trunk.—The segments related respectively as 16:6:4:5:4: 26:2:1. The fourth abdominal segment six times the length of the preceding segment. Legs.—The denna similar on each of the pairs of legs; the superior claw armed with two small teeth situated respectively from the base and apex of the claw, at distances equal to one third the length of the latter. The inferior claw lanceolate, unarmed. A single tenent hair in relation with each foot. Furcula.—Vhe dentes very nearly twice the length of the manubrium; the mucrones tridentate, similar to the typical form found in the genus. Coloration.—The ground colour yellowish, the appendages paler. The third joint of the antennz with an apical suffusion of violet-black, the fourth joint almost white with a sight basal suffusion of violet. The eyes ona black patch on each side of the head; a purplish lateral suffusion on each side of the head behind the eye-patch. An extensive suffusion of the same colour on either side of the mesothorax, and a broad conspicuous band of similar colour along the distal portion of the fourth abdominal seoment., The femora of the hind pair of legs almost entirely violet. Length 3°6 mm. (including the head). One example, taken under dry leaves and stones on the edge of a jungle stream, Maddathoray, W. base of W. Ghats, Travancore, S. India (WV. Annandale, November 18th, 1908). No. ae Indian Museum Coll. This species 1s closely allied to LZ. maximus Schott *, from the Kamerun. It is separable, however, on account oo the great size of the fourth abdominal segment; in the inferior claws of the feet being lanceolate, with its lower margin curved instead of being straight ; and in the stouter tenent hair. * “Tnsektenfauna von Kamerun: Collembola,’ Bihang till K. Sy. Vet.-Akad. Handl., Bd. 19, Afd. iv. no. 2, p. 11, pl. mi Je) Or ORIENTAL COLLEMBOLA, Genus Enromoprya Rondani. + Entomobrya Rondani, Dipterol. Ital. Prodr. vol. iv. Degeeria Nicolet, Rech. p. s. a Vhist. d. Podur., 1842, p. 70. Entomobrya Borner, ‘ Das Syst. Coll.,” Mitt. Naturhist. Mus. Hamburg, 1906, xxii. p. 164, [Including Homidia Borner and Sinella Brook. | *ENTOMOBRYA kama, spam. (Pl. VIL. fig, 33;° Pl. VIEL, figs. 34-36.) Antenne truncum longitudine fere aequantes. Segmentum abdominale quartum plus dimidia trunci parte occupans. Mucrones denticulis duobus atque seta spiniforme una instructi. Flava; anteriore parte capitis, marginibus segmenti secundi thoracis, segmentis secundis tertiisque abdominis, et fascia transversa posteriore quarti, nigris. Long. 175-2 mm. Head.—Slightly longer than broad ; clothed with short, scattered plumose hairs and a dorsal tuft of very long, stout setee, ciliated along one side at their apices. The eyes eight in number on each side. Antennee.— Usually very nearly equal in length to the body excluding the head, but in some specimens they exceed the length of the body. Four jointed, densely clothed with hairs, dispersed among which are slender sete. The joints related to one another in length as 5:6:6:11; the ring-like basal joint, typically present in the genus Hntomobrya, is absent. Trunk.—Fusiform, clothed with short, curved plumose hairs, scattered among which are slender sete. The thorax and first two abdominal ‘segments provided dorsally with very long, stout sete, ciliated along one side at their apices (fig. 36); a tuft of similar setz at the apex of the abdomen. The trunk segments related proportionately in length as 11:5:3:6:6:45:5:1 (fig. 34). Legs.—Clothed with hairs among which are slender sete. The superior claws moderately slender and bidentate along the inner margin (fig. 33); the teeth situated respectively from the apex of the claw at a distance equal to one quarter and one half the total length of the latter. The inferior claws a little more than half the “length of the superior claws, acuminate and sharply pointed, the margins without any teeth. A single tenent hair in relation to each foot. Furcula.—As long as the trunk excluding the mesothorax ; densely clothed with hairs, dispersed among which are slender sete. The dentes a little longer than the manuhriwm, very slender, and each is provided with a double row of small peg-like spines along the proximal half of its inner aspect. The smwerones tri- dentate, with a curved terminal tooth, a stout erect conical middle tooth, and an oblique acicular posterior tooth (fig. 35). Coloration.—Light ochre-yellow marked with patches of violet- black. The eyes on a large irregular black area on each side; a 96 PROF, A. D. IMMS ON small violet-black patch between the bases of the antennz and frequently prolonged into a narrow streak on each side to unite with the eye-patch. A triangular area of the same colour on the middle of the hind border of the mesothorax, and a slight suffusion on each side near the outer margin of that segment. The meta- thorax and the first abdominal segment entirely yellow; the second abdominal segment violet-black, with the exception of a narrow irregular yellow area along its anterior margin ; the third abdominal segment entirely deep violet-black; the posterior half of the fourth abdominal segment densely suffused with violet-black; the fifth and sixth abdominal segments yellow. The first and second joints of the antenne yellow, the second joint in most specimens with a slight violet suffusion at its apex ; the third and fourth joints purplish. Length 175-2 mm. Fifty-one specimens taken under dead leaves in Calcutta, where it appears to be very plentiful (/ndian Museum Collector, January 16th, 17th, 18th, and 20th, 1908, and February 18th, 1910). Nos. a and — Indian Museum Coll. In all the individuals examined the colour pattern was found to be very constant, practically no variation being observed. In specimens that had been kept in alcohol for two years, the ground colour is much paler and cream-coloured. The long, stout sete (fig. 36) fall off very readily in alcohol specimens, and very many specimens have lost them altogether. In many cases the antenne are very much shrivelled in saleohol, and in a large proportion of the specimeus the tenent hair is either broken or lost from one or more of the legs. ENTOMOBRYA KALI LUTEA, Var. NOV. This differs from the typical form in having the fourth abdominal segment entirely yellow. One specimen taken among low herbs and grass at Simla circa 7900 ft. (V. Annandale, May 12th, 1908), No. 88t4 6 Indian Museum Coll. EnroMOBRYA CRASSA, Sp.n. (PI. VII. figs. 30, 31.) Segmentum tertium abdominis quartum longitudine Sere equans. Mucrones denticulis duobus atque seta spiniforme una instructe. Color fava-viridis. Long. 1:5 mm. Head.—The eyes eight in number on each side (fig. 31); the post-antennal organs wanting. Antenne.—The joints mutually related in length in the pro- portion of 4: 6:6: 9. Trunk.—Provided with pilose hairs of various lengths. The segments related to one another in length as 8:7:4:5:8: 10: 33 2. Legs.—Clothed with pilose hairs among which are a few stouter ORIENTAL COLLEMBOLA, 97 sete. The superior claw of each foot slender and acuminate, with a small tooth situated at the middle of the inner margin. In some examples there is a second, and much smaller tooth, placed half way between the former tooth and the apex of the claw. The inferior claw of each foot slender and tapering, a little more than half the length of the superior claw, unarmed, A single very slender tenent hair to each toot. Furcula.— 7 —9 mm. long; the manubrium one half the length of the dens. The muero =}; mm. long (fig. 30), tridentate, with a slender, curved terminal tooth, a vertical and somewhat stouter tooth anterior to the latter, and a minute backwardly directed spiniform tooth. Coloration.—When alive, dull dark green to the naked eye, In alcohol specimens, pale greenish yellow suffused with dark indigo-blue. The eyes on a black patch on each side of the head, the two patches joined together by a transverse band, which passes across the head just behind the bases of the antenne, On the middle of the dorsal side of the head is a prominent black sagittate marking thus |, with its apex directed backwards, The antenne and legs darker than the body, somewhat purplish in colour. The furcula yellowish white, Length varying from 1:5-1-8 mm. Six examples, taken in ants’ nests under stones about half a mile below the base of the Satopanth Glacier, Garhwal Himalaya, 12,500 ft. (A. D. Imms, May 25th, 1910). 8609 No. Sia Indian Museum Coll, This species differs from typical members of the genus #nto= mobrya, and resembles the genus Orchesella, in the very short fourth abdominal segment, It agrees with the genus Hntomobrya in the characters of the antenne and furcula, in the eyes, and in the absence of post-antennal organs, Hntomabrya anomala Carpenter * similarly possesses a relatively short fourth abdominal segment. The latter species, however, may ultimately be separated into a new genus on account of its possessing six- jointed antenne. Genus Serra Lubbock, Seira Lubbock, * Notes on the Thysanura,” pt. iv., Trans. Linn. Soc. 1870, vol. xxvii, p. 279, pl. 45 (= Ptenuwra, Templ., Born.). Sira Tullberg, “ Sveriges Podurider,” Kongl, Svensk, Vetensk,- Akad. Handl, 1872, vol, x, p. 41, pl. vi. SEIRA FRIGIDA, sp.n. (PI. VIII. figs. 41, 42.) Unguiculus superior tridenticulatus ; denticuli perparvi, ita colla- cati ut unus post alierwm insertus sit. Unguiculus inferior lanceolatus, inermis. Mucrones breves, bidentati. Articulo quarto * “On two new Irish species of Collembola,” Sci. Proc. Roy. Dublin Soe, yol, xi, (n. s.) 1906, p. 40, pl. 11. Proc. Zoou. Soc.—1912, No, VII. 7 98 PROF, A. D. IMMS ON antennarum primum et secundum longitudine cequante. Tibice pilis clavatis singulis instructe. Long. 2°5 mm. Head.— As long as the combined length of the meso- and meta- thorax. The eyes as usual in the genus. Antenne.—Kqual in length to the furcula (in some examples slightly shorter than that organ). ‘The joints related to one another in length as 5: 8:9: 13. Trunk.—Invested with scales, among which are prominent curved sete, ciliated at their apices along one side, and disposed in the following manner : a prominent * frill” or ‘ collar” along the anterior border of the mesothorax, and a second group of such sete near the posterior margin of that segment. A few scattered setee on the metathorax, and a tuft of similar but shorter sete at the extremity of the abdomen. The segments related to one another in length as 8:6:5:5:5: 23:5: 3. Legs.—The claws of the feet similar on all pairs of legs (fig. 41). The superior claws moderately slender, sightly curved at their extremity, and armed with three minute teeth along the inner margin. The inferior claws lanceolate, entire, slightly curved at their apices. A single tenent hair in relation to each foot. Furcula.—In length measuring *8 mm.; the manubriwm related to the denies in length as 13: 19—or approximately as 2: 3. The dentes without ventral scales; slightly curved upwards at their apices (fig. 42). The mucrones only imperfectly separated off from the dentes, armed with a prominently curved terminal tooth and a basal spiniform tooth. The latter directed back- wards in an oblique fashion, almost reaching to the apex of the mucro (fig. 42). Coloration.—Dirty yellowish white, marked with irregular patches of blue-black disposed in the following manner :—A prominent patch on either side of the head enveloping each eye-group, and united by a transverse band, which crosses the head immediately behind the bases of the antenne. I? s + In * Termitenleben auf Ceylon.” von K, Escherich, Jena 1911, p. 244. ORIENTAL COLLEMBOLA. wy 5:26:2:2. The fourth abdominal segment at least five times as long as the preceding segment. Legs.—Provided with short straight set. The superior claw of the third pair of legs stout and thick, except at the apex where it becomes swollen and membranous (fig. 87); one large acicular tooth situated at the middle of the inner margin, a minute tooth immediately in front of the former, and a small tooth close to the apex of the claw on either side. The inferior claw wide and plate-like, bifid. The claws of the first and second pairs of legs smaller and somewhat shorter. A single tenent hair in relation to each foot. Furcula.—Moderate in size, stout, *4 mm. long, scaled ven- trally. When closed up beneath the abdomen the mucrones reach to the anterior border of the fourth abdominal segment. The manubrium divided imperfectly into proximal and distal portions (fig. 88). The dentes just about half the length of the manubrium, short and stout; each provided along its outer aspect with a dorsal row of five very large scales, a row of two similar scales along the inner side, and a small terminal scale just beneath the mucro (figs. 88 and 89). The proximal inner scale equal in length to the proximal outer scale; the outer and inner apical scales longest of all, the inner slightly longer than the outer. The mwuero very small and armed with four teeth (fig. 89); a very small terminal tooth, and three dorsal teeth situated one behind the other; the posterior and middle teeth of the row curved and pointed, the anterior (or proximal) tooth blunt and rounded, Coloration.—In alcohol, white. Length 1-1:15 mm. Twelve specimens taken from a nest of Termites at Rhamba, south end of Lake Chilka, N.E. Madras (VV. Annandale, March 3rd, 1910). The Termite has been subsequently identified by Prof. Silvestri as Termes redemanni Wasm. N 444 Oo. — Indian Museum Coll. Sub-order SYMPHYPLEONA Born. Fam. SMintHvuRID# Lbk. Sub-fam. SMINTHURIDIN2 Born. Genus SMINTHURIDES Born. + Sminthurus (Smynthurus) Latreille, Hist. Nat. 1804, T. viii. p. 79 (ad partem). Sminthurides Borner, “ Zur Kennt. der Apteryg.-Fauna von Bremen,” Abh. Nat. Ver. Bremen, 1901, Bd. xvii. p. 91. * SMINTHURIDES APPENDICULATUS, sp.n. (PI. XII. figs. 83-86.) Articulus ultimus antennarwm longissimus, vie annulatus. Pili clavati in tibiis nulli. Ungwiculi superiores inermes ; ungur- culi inferiores in setam longam prolongati. Unguiculi infertores 118 PROF. A. D. IMMS ON pedum posteriorum etiam tribus appendicibus filiformibus instructi. Mucrones furcule lati, laminati. Long. 5-75 mm. Antenne.—Slender, the joints related to one another in length as 8: 11:22:32; the terminal joint only with slight indications of annulation (fig. 83). Trunk.—The abdomen provided dorsally with a few short, curved, scattered hairs. Legs.—The first and second pairs similar (fig. 85); the superior claws very long, at least two and a half times as long as the breadth of the tibia, slightly curved at their apices, unarmed. The inferior claw approximately one fifth longer than the superior claw, setiform and whip-like, usually with a minute tooth on its ventral aspect towards the base. The superior claws of the third pair of legs shorter and smaller than those of the preceding pairs; the inferior claws whip-like, armed at about the middle of their length with a group of three filiform dorsal appendages, and a small tooth situated close to the latter on the ventral surface (fig. 84). No tenent hairs to the feet. The tibie of the third pair of legs provided with three apical sense organs (#) on the inner side (fig. 84). Ventral Pube.— Very short, without elongate vesicles. Purceula.—The dentes, without. their mucrones, equal in length to the abdomen; slightly eurved ventralwards. The mucrones very large (fig. 86), at least as wide as the maximum width of the dens, lamellate. Coloration.—Ground colour leaden, the legs and spring paler. The eyes on a black patch on each sideof the head, The antenne dark leaden coloured with a purplish suffusion. A pale yellow dorsal area on the head, bearing a small bluish-purple patch between the eyes. The trunk indigo-blue dorsally, with small pale yellow markings. Length varying from -5—-75 mm. Twenty-one specimens taken on the surface of water at Calcutta CUndian Museum Collector, January 9th, 21st, and 22nd, 1908). : 4392 Nos. BR and 3 : 16 ig Indian Museum Coll. TIl. A CATALOGUE OF THE ORIENTAL CoLLEMBOLA. In defining the area comprised within the Oriental region, I have followed Blanford * in taking for its northern boundary the limits of forest growth in the Himalayas ; while as regards the south-eastern boundary, I have followed the later views that are wellsummarised by Pelseneer T and supported by the results of the “Siboga” expedition. Pelseneer proposes the name of & Weber’s Line” for the south-eastern boundary, which is regarded as passing east of Timor and through the Banda and Molucca Seas. * “The Distribution of Vertebrate Animals in India, Ceylon, and Burma.” Phil. Trans. Roy. Soc. vol. 194, 1901, p.347. : pe + “Ta Lignede Weber, Limite Zoologique de Asie et de l’Australie.” Bull. Belg. Acad. 1904. ORIENTAL COLLEMBOLA. 119 With the small amount of knowledge of Oriental Collembola at -one’s disposal it is impossible to make any generalisations. Two features, however, stand out as notable:—(1) The paucity of the members of the Sub-order Symphypleona, which is represented by only three genera, and as many species, out of a total of fifty- three species of Oriental Collembola. (2) The relative pre- ponderance among species of the genus Paronella. OO Ee eS) 14. Y5. 16. Sub-order ARTHROPLEONA Born. Fam. Popurip# Lbk. Sub-fam. HypoGastrurIn«% Born. . Xenylla obscura, sp.n. India (W. Himalayas). Sub-fam. Acnorutin Born. . Protanura krepelint Born, Java. (Borner; Mitt. Natur- hist. Mus. Hamburg, 1906, xxiii. p. 169.) . Oudemansia cerulea Schott. Thousand Islands. (Schott ; Ent. Tidskr. 1893, p. 172.) . Achorutes lipaspis Born. Java. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxii. p. 170.) . A. hirtellus Born. Java. (Borner; loc. cit. p. 170.) . A. armatus Nic. Sumatra. (Oudemans; Zool. Ergeb. einer Reise in Niederl.-Ostind., Hft. i. p. 89.) Ceylon. . A. crassus Oud. Sumatra. (Oudemans; loc. cit. p. 90.) . Ceratameria (Schéttella) maxima Schott. Java. (Borner ; Mitt. Naturhist, Mus. Hamburg, 1906, xxiil. p. 167.) Sub-fam. NEANURIN«A Born. . Pseudachorutes anomalus, sp.n. India. (BK. Himalayas.) . Neanura corallina, sp. n. Ceylon. . WV. pudibunda, sp.n. Lower Burma. . WV. intermedia, sp. n. India (W. Himalayas). . WV. fortis Oud. Java, Sumatra, and Saleyer. (Oudemans ; Zool. Ergeb. einer Reise in Niederl.-Ostind., Hft. 1. p. 91.) Sub-fam, OnycuruRiIn& Born. Onychiurus (Lipura) fimetarius Burm. Sumatra, (Oude- mans ; loc. cit. p. 90.) Fam. ENtToMOBRYID& D. T. Sub-fam. Isoromina Schiff. Isotoma crassicornis Schott. Sumatra. (Schétt; Ent. Tidskr. 1893,.p. 172.) I. nigropunctata,sp.n. India (E. Himalayas). 120 Wha 18. PROF, A. D. IMMS ON Sub-fam. TomoceriIn& Schaff. Tomocerus (Macrotoma) montanus Oud. Sumatra. (Oude-- mans; Zool. Ergeb. einer Reise in Niederl.-Ostind., Hft. 1. 10 Ske) Sub-fam. Herrromuricin#&, sub-fam. nov. Heteromuricus cercifer, gen. et sp. n. India (Bengal). Sub-fam. EnroMosryiIn& Schiff. . Isotomurus (Isotoma) palustris Mill., India (Bengal). Sub.- sp. tricuspis Born. Java. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxiii. p. 173.) . Lepidocyrtus robustus, sp. n. India (Travancore). . L. brauert Born. Seychelles. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxiii. p. 176.) . L.javanus Born. Java. (Borner ; loc. cit. p. 176.) . L. variabilis Oud. Sumatra and Java. (Oudemans; Zool. Ergeb. einer Reise in Nieder].-Ostind., Hft. i. p. 84.) . L. javanicus Oud, Java. (Oudemans ; loc. cit. p. 85.) . Entomobrya kali, sp. n. India (Bengal). Var lutea nov. India (W. Himalayas). . E. florensis Oud. Floves. (Oudemans; loc. cit. p. 86.) . LE. longicornis Oud. Sumatra and Java, (Oudemans ; loc. CEL Ds Sin) . Sera (Sira) annulicornis Oud. Java, (Oudemans ; loc. cit. oh (Sidhg) . S. sumatrana Oud. Sumatra. (Oudemans; Joc. cit. p. 88.) . S. brahma, sp.n. India (United Provinces). . Pseudosira indra, sp.n. India (Bengal). . Dicranocentroides fasciculatus, gen. et sp.n. India (W.Hima- layas). . Heteromurus tenwicornis Born, Java. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxiii. p. 177.) . H. tetracantha Born. Java. (Bérner; loc. cit. p. 177.) . H. (Templetonia) sp.? Java. (Oudemans; Zool. Ergeb. einer Reise in Niederl.-Ostind., Hft. i. p. 89.) . Cremastocephalus celebensis Schiif. Celebes. (Schaffer ; Archiv f. Naturges., 1898, p. 407.) . C. montanus, sp. n. India (E. Himalayas). . C. indicus, sp. n. India (United Provinces and Bengal). . Paronella tarsata Born. Java. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxiii. p. 177.) . P. setigera Born. Java. (Biérner ; loc. cit. p. 178.) , E. borneri, Sp. a. Niepail: . P. travancorica, sp. n. India (Travancore). . P. gracilis, sp. n. India (W. Himalayas). . P. phanolepis, sp.n. India (W. Himalayas). 5. P. insignis, sp.n. India (Travancore). ORIENTAL COLLEMBOLA, P21 46. [diomerus pallidus, gen. et sp.n. India (Travancore), 47. Cyphoderus simulans, sp.n. Burma. 48. C. javanus Born. Java. (Borner ; loc. cit. p. 180.) 49. Pseudocyphoderus annandalei, gen. et sp. n. India (N.E. Madras). 50. Cyphoderodes ceylonicus Silv. Ceylon. (Silvestri ; in Ter- mit. auf Ceylon von E. Escherich, 1911, p. 245.) Sub-order SYMPHYPLEONA Born. Fam. SMINTHURID2@ Lbk. Sub-fam. SMINTHURIDIN&Z Born. 51. Sminthurides appendiculatus, sp. n. India (Bengal). Sub-fam. CorynepHorin« Abs. 52. Corynephoria jacobsoni Abs. Java. (Absolon; Entom. Ztg. Wien, 26, 1907, p. 338.) . Sub-fam. Dicyrtromin# Born. 03. Ptenothrix gracilicornis Schiiff., subsp. gibbosa Born. Java. (Borner; Mitt. Naturhist. Mus. Hamburg, 1906, xxiii. p. 185.) IV. A Summary or GENERAL ConcLusSIONS. 1. Four genera and twenty-seven species of Collembola are de- scribed as new, and three species belonging to as many genera were already known, Out of a total of thirty-one species, five are Palearctic, and were obtained above the limits of forest- growth in the Himalayas. The remaining species are Oriental. 2. The Palearctic species are all referable to well-known genera, and were not met with in the Oriental region. 3. Among the Oriental species it has been found necessary to erect four new genera, 1. e.:—IJdiomerus, Dicranocentroides, Heteromuricus, and Pseudocyphoderus. The remaining species all pertain to genera whose range extends into at least one other zoo-geographical region. 4. Among the new forms discovered, the most remarkable is Heteromuricus cercifer, gen. et sp.n. It is unique among Collem- bola in possessing a median cercus to the fifth abdominal segment. A new sub-family—the Heteromuricine—is proposed for its reception. Psewdocyphoderus gen. nov., with a single species, is described from the neighbourhood of Lake Chilka, where it occurs in Termites’ nests. 5. The total number of Collembola known from the Oriental region amounts to fifty-three species comprised within twenty- seven genera, Of these only three genera, each with a single species, are members of the sub-order Symphypleona. 122 PROF. A. D. IMMS ON V. EXPLANATION OF THE PLATES. The figures were made with a Leitz drawing apparatus under various magnifi- cations. Wherever arrows are represented they indicate the direction of the anterior end of the body. Prate VI. Pseudachorutes anomalus, sp. un. Fig. 1. The right mucro viewed from the lateral aspect. . The eyes and post-antennal organ of the right side. . The right foot of the first pair of legs. . An outline figure of the furcula seen from the dorsal side. Bm owrDr Xenylla obscura, sp. nD. . An outline figure of the dorsal aspect of the furcula. . A dorso-lateral view of the anal spines and their papilli. . The mucro and apical portion of the dens of the left side viewed from the inner aspect. . The hamula. . The right leg of the first pair. £6 CO TO Ot Neanura pudibunda, sp. n. Fig. 10. The antenna, eyes, and post-antennal organ of the left side. 11. The left foot of the third pair of legs. 12. The insect viewed from the dorsal side. Neanura intermedia, sp. n. Fig. 12. The left antenna seen from the dorsal aspect. 14, The left foot of the first pair of legs. Tsotomurus palustris Mull. Fig. 15. The mucro, together with the apex of the dens ; right side. Isotoma siva, sp. 0. Fig. 16. The left foot of the first pair of legs. 17. The mucro and apex of the dens of the left side; viewed from the outer side. 18. The eyes of the right side. Puate VII. Tsotoma siva (continued). Fig.19. The insect seen from above. Neanura intermedia (continued). Fig. 20. The eyes of the left side. Tsotomurus patustris (continued). Fig.21. The right foot of the first pair of legs seen from the inner side. 22. The eyes and post-antennal organ of the right side. Neanura corallina, sp. n. Fig. 23. The insect viewed from above. 24. The left antenna seen from the ventral aspect. 25. The eyes of the left side. 26. The third leg, left side. LIsotoma nigropunctata, sp. 0. Fig. 27. The eyes and post-antennal organ of the right side. 28. The right foot of the third pair of legs seen from the imner aspect, 29. The apex of the dens of the right side together with the mucro. Fig. 30. 31. Fig. 48. Fig. 49. 50. 61, Fig. 62. 63. 54, Fig. 55. ORIENTAL COLLEMBOLA. 123 Entomobrya crassa, sp. n. The mucro and distal portion of the dens of the right side. The eyes of the right side. Pseudosira indra, sp. n. . The left mucro together with the apical portion of the dens, viewed from the inside, Entomobrya kali, sp. n. . The right foot and apex of tibia of the third pair of legs; inside view. Prats VIII. Entomobrya kali (continued). . The insect viewed from above. (The specimen figured has lost the longer sete from the body.) The left mucro and apical portion of the dens; inside view. Typical sete from the mesothorax. Pseudosira indra (continued). . The eyes of the right side. . The right foot of the third pair of legs. . A typical seta from the anterior margin of the mesothorax. . A typical body-scale. Seira frigida, sp. n. . The left foot of the third pair of legs. The mucro and apex of the dens of the left side; inside view. Seira brahma, sp. n. The left foot of the third pair of legs. . The left mucro and apical portion of the dens; viewed from the inside. Dicranocentroides fasciculatus, gen. et sp. n. The right foot of the first pair of legs. . A portion of the inner aspect of the dens showing the characteristic spines. - Hairs from various regions of the body. (a) From the apical joint of the antenna. (6) From the tuft on the second antennal joint. (c) An acuminate hair from the legs. Sinella montana, sp. n. The right foot and apex of the tibia; third pair of legs. Sp., Spine-like setae. Heteromuricus cercifer, gen. et sp. n. The right foot of the third pair of legs. The cereus viewed laterally. One of the larger body-scales. Puate IX. Heteromuricus cercifer (continued). The insect viewed from the right side. (The head is inclined at a greater angle with the trunk than is represented.) The eyes of the right side. The left mucro viewed from the outer aspect. Dicranocentroidés fasciculatus (continued). The left mucro viewed from the outer side. d., dens; 7. ¢., lateral tooth, 55 a, Body-scales, Fig. 69. Fig. 70. ile 72. 73. 74., Fig. 75. 76. Fig, 77. 78. Fig. 79. Fig, 80. ON ORIENTAL COLLEMBOLA, Sinella montana (continued). The right mucro seen from the outside. . (a) A seta from the mesothorax. (6) A seta from the extremity of the abdomen. Cremastocephalus indicus, sp. n. . The right foot of the third pair of legs. . The apex of the dens with the mucro of the left side; inner aspect. Cremastocephalus montanis, sp.n. . The apex of the dens with the mucro of the left side; inner aspect. Idiomerus pallidus, gen. et sp. n. . The right mucro viewed from the outer side. Paronella travancorica, sp. vi. . The left foot of the second pair of legs; inside view. ps., pseudonychium ; t.h., tenent hair. . The left foot of the second pair of legs viewed from above. ps., pseudo- nychium ; ¢.h., tenent hair. . The eyes of the right side. . The left mucro seen from its outer aspect. . Body-scales. PLATE X. Paronella travancorica (continued), The insect seen from the right side. Dicranocentroides fasciculatus (continued). The insect seen from the right side. (The legs have been drawn too short, the hind pair should reach almost to the extremity of the abdomen.) Paronella phanolepis, sp. n. The left foot of the first pair of legs. Paronella borneri, sp. n. The mucro and apex of the dens viewed from the outer side; right side. d., dens; m., mucro; s.o., scale-like organ. The foot and distal extremity of the tibia of the first pair of legs. The hamula. The apex of the organ is directed towards the hinder end of the animal. c., corpus; 7.. ramus; s., seta. Hairs and scales. (a) From the anterior border of the mesothorax. (8) From the fore leg. (¢c) From the general surface of the body. The eyes of the right side. Poate XI, Paronella borneri (continued). The insect viewed from above. Entire leg of first pair. Paronella gracilis, sp. n. The left foot of the first pair of legs seen from the inner side, The left mucro seen from the inner side. Paronella phanolepis (continued). The right mucro seen from the outer side. Paronella insignis, sp. n. The insect viewed from the left side. Tee eis), WS) a, WT, XCHULL West, Newman lith. DEVELOPMENT OF THE BILL IN ARDEA CINEREA. ON THE BILL OF THE HERON. 125 Puate XII. Paronella insignis (continued). Fig. 81. The right foot of the third pair of legs, seen from the outer aspect. 82. The right mucro seen from the outer aspect. Sminthurides appendiculatus, sp. n. Fig. 83. The left antenna seen from the inner side. 84. The left hind foot, inner side. 85. The left foot of the first pair of legs seen from the inner side. 86. The right mucro seen from its outer aspect. d.¢./., dorsal inner lamella; d.o.1., dorsal outer lamella; v.2., ventral lamella. Pseudocyphoderus annandalei, gen. et sp. n. Fig. 87. Foot of third pair of legs. 88. The fureula viewed from the dorsal side. #.s., terminal scale. 89. The left dens and mucro from the outer side. ¢. s., terminal scale. Cyphoderus simulans, sp. n. Fig. 90. The left foot of the second pair of legs. 91. The left mucro seen from its outer aspect. &. Ontogenetical Transformations of the Bill in the Heron (Ardea cinerea.) By Prof. P. P. Susugin, C.M.Z.S., Kharkoy, Russia. {Received June 3, 1911: Read November 7, 1911. | (Plate XITT.*) The birds of the subfamily Ardeine are known to have a conical, pointed, spear-shaped bill with a simple rhamphotheca. The curious fact that these features are acquired only in a late post-embryonic stage seems to have attracted little attention. I have been able to trace a gradual development of these features in a series of embryos and young birds of Ardea cinerea, collected and generously presented to me by one of my friends, Mr. J. G. Sobolev, of Moscow. 3 In an embryo, in which the feather-papille on the back have just assumed a conical shape (length of the gape about 12 mm.), the bill is straight and rather slender, the tip of the upper jaw is conspicuously swollen (not only owing to the presence of the so-called egg-tooth), and the culmen is concave; a furrow runs from the nostril to the base of the swollen tip (Pl. XIII, fig. 1). In an embryo about one day before hatching (length of gape 22mm.) the form of the bill has already changed ; it is thicker, its swollen tip is not so prominent and is slightly hooked, and the culmen is not so coneave. The horny sheath of the bill is mani- festing itself; the covering of the tips of both jaws is thicker and more solid, and the covering of the tip of the upper jaw is marked off by a raised area; a furrow anterior to the. nostril, and a space * For explanation of the Plate see p, 126, 126 ON THE BILL OF THE HERON. of softer and finely wrinkled skin between the eye and the nostril divide the covering of the upper jaw into a dorsal and a paired lateral plate. The covering of the mandibular rami is marked by the presence of some parallel oblique ridges; these are perhaps still more conspicuous just at the time of hatching, but quickly disappear afterwards (fig. 2). One day after hatching (length of gape 25mm.) the bill is longer and conspicuously thicker, and the swelling of the tip has almost disappeared. The covering of the tip of the upper jaw is still marked off by its texture and relief, and the tip-covering of the mandible is marked off by two irregular crack-like furrows as well as by its solid texture. The division between the upper and lateral plates of the upper mandible is plainly visible (fig. 3). About three days after hatching (length of gape 32 mm.) the bill has nearly assumed its conical shape, but is still relatively short and thick and the tip is still conspicuously hooked. The horny covering of the mandible-tip is still marked off by irregular furrows; in the upper jaw it is no more distinct; the lateral furrows before the nostril, dividing the upper and paired lateral horny plates, are still clearly visible (fig. 4). These changes seem to deserve attention on more than one ground. The simple rhamphotheca proves to be only a late stage of the compound one, as very clear vestiges of separate pieces are visible in younger stages. In the upper jaw we find a tip piece, a dorsal piece, and a paired lateral piece ; in the mandible there are a tip piece and a paired lateral piece. The form of the Ardeine bill proves to be a derivative one. The presence of the tip-hook in the nearest relatives of the Herons, Scopus and Baleniceps, 1s hence a primitive feature. In younger stages the shape of the bill, combined with its compound rhamphotheca, recalls very nearly that of a Cormorant, especially of a young one about the time of hatching, and also of the nestling of a Frigate-bird, and of a Pelican about the time of hatching. This points once more to the affinities of the Ardez and Steganopodes. ‘The change in shape of the bill in the Ardeine is obviously due to their habits of spearing their prey instead of sjatching as most of the Stega- nopodes do, The peculiar heron-lke shape of the bill in the Darter (Plotus anhinga) is connected with the same habits, and the likeness of the bill’s shape in the Herons and Plotus is to be considered as a case of parallel evolution. The transitory ridges on the mandibular rami recall remotely—by their direction also —the structures so much developed in the Anseres, and also, perhaps, the indentations of the bill in the fossil Odontopteryzx. EXPLANATION OF PLATE XIII. Fig. 1. Bill and head of an embryo of Ardea cinerea, length of gape 12 mm. 1X2. 2. The same, one day before hatching. 1X1°75. 3. Young bird, one day after hatching. 1X1‘. 4, The same, about three days after hatching. 1X1‘. ON MAMMALS FROM WESTERN CHINA. NOL 9. The Duke of Bedford’s Zoological Exploration of Hastern Asia.—XV. On Mammals from the Provinces of Sze- chwan and Yunnan, Western China. By OLp¥FiELp Tuomas, F.R.S., F.Z.8.* [Received September 13, 1911: Read October 24, 1911.] After the departure of his assistants, Dr. J. A. C. Smith and Mr. Kingdon Ward, down the Yang-tze, with the remarkable collection of mammals which formed the subject of paper No. XIII. of the present series, Mr. Maleolm Anderson worked on by himself froin September 1910 to the end of March 1911, when he brought back to Shanghai the series on which the present paper is based. During this period he explored a number of localities in Western Sze-chwan and N. Yunnan, and has been rewarded by finding a considerable and quite unexpected number of species additional to those previously sent. He has been especially fortunate in discovering novelties among the Shrews and Voles, while of the peculiar little Insectivores allied to Uropsilus he has sent home the material on which I have found occasion to base two new genera. Altogether the set consists of about 160 specimens belonging to 33 species, and no less than eleven prove to need description as new. To our great loss and regret Mr. Anderson now proposes to give up the arduous life of the field collector, and this is therefore the last paper to be written on his collections for the Duke of Bedford’s Exploration of Eastern Asia. On this account it is suitable to give a few words of appreciation for the manner in which he has risen to the opportunity afforded by our President’s continued generosity. From the commencement of the work in 1904 to the sending home of this last valuable collection in 1911 Mr. Anderson has worked for the Exploration with superb enthusiasm and success, and in the extent to which his collections have revolutionized our knowledge of an extended part of the earth’s surface he has made a record which, so far as I know, has never been equalled, the nearest approach to it being Mr. OC, H. B. Grant’s collections for Mr. Rudd’s Exploration of §8, Africa T. In turn Mr. Anderson has visited and collected in Japan and its islands, both the small southern ones and the large northern Hokkaido and Saghalien, Korea, N. China and Mongolia, Shen-si, Shan-si, Kansu, Sze-chwan and N, Yunnan, his collecting-localities being dotted through all the previously most unexplored parts of this little-known area. Over 2700 mammals have been collected, besides many birds, and, as is natural, a large number of novelties have been found among them. * Published by permission of the Trustees of the British Museum, + Cf. P.Z.S. 1908, p. 555. 128 MR. OLDFTELD THOMAS ON On this occasion it may be useful to give a list of the papers which have been written on the mammals collected by Mr. Anderson :— J. Japan. ~P.Z. 8. 1905, vol. 1. p. 331. 60ispp. IT. Korea and Quelpart. 1906, p. 858. 9 spp. III. Mindanao. 1907, p. 140. 6s IV. Saghalien and Hokkaido. 1907, p. 404, 22 spp. V. Korea (II.). 1907, p. 462. 13 spp. VI. Shantung. 1908, p. 5. 6 spp. Vil. Tsu-shima. 1908, p. 47. 11 spp. (VIII. Fishes of Korea. 1908, p. 59 TX. Mongolian Plateau. 1908, p. 104. 9 spp. X. Chih-li and Shan-si. 1908, p. 635. 20s XJ. Shan-si and Shen-si. 1908, p. 963. 33 spp. XII. 8. Shen-si. 1910, p. 635. 3 spp. nn. XIII. Kansu and Sze-chwan. 1911, p.158. 48 spp. XIV. S. Shen-si. 1911, p. 687. 31 spp. XY. Sze-chwan and Yunnan. 1912, p.127. 32 spp. The localities at which the present collection was made being somewhat scattered, and but little known, it may be helpful to give a list of them :— Chin-fu-san, a mountain near the city of Nan-chwan, south of Chung- king, not far north of the Sze-chwan— eae chow 3? bor den. Hwa-yin-san, a limestone peak 50 miles N.K. of Chung-king. Caves near Pen-hsien, about 35 miles N.W. by N. of Chen-tu. Wei-choe, about 60 miles N.W. of Chen-tu, in the narrow valley of the Si-ho (or Sung-pan-ho). Wen-chwan, 12 miles lower down the Si-ho. Yuen-ching-hsien, 8.W. of Ya-chow. ‘Part of the humid range in which Mount Omi lies.” Ning-yuen-fu, 8. of Fu-lin, on the Tung-ho. Chao-tung-fu, N. Yunnan, about 103° 40’ E., 27° 30’ N. 1, Smt * sp. (S. rhesus group). 2. 2678. Mts. 30 miles 8.W. of Kia-ting-fu, Sze-chwan. 2. RHINOLOPHUS FERRUM-EQUINUM Schr. 3. 2592 (in al.), Caves near Pen-hsien, 35 miles N.W. of Chen-tu. 3000. 3. RHINOLOPHUS CoRNUTUS PUMILUS K, And, 2. 2587, 2588, 2589, 2590 (in al.), 2591 (in al.) Caves near Pen-hsien, 35 miles N.W, of Chen-tu, 3000’. 4, HiIpPosIDEROS ARMIGER Hodgs, o . 2585,2586, Caves near Pen-hsien, Central Sze-chwan, 3000’. * Simia Iinneus, Type S. sylvana, the Barbary Ape; Macaca and Pithecus auctorum; see Thomas, P. Z.S. 1911, p. 125. MAMMALS FROM WESTERN CHINA. 129 5. NycoraLus pLANcyi Gerbe. 3. 2677. Ya-chow-fu, Sze-chwan. 2500". This Bat is just distinguishable—by its rather smaller size— from the Nepalese WV. labiatus Hodgs., with which it shares the reduced length of the outer incisors. 6. Urorsinus soricirrs M.-Edw. 3. 2605, 2637. Wei-choe, on Si-ho River, W. Sze-chwan. 9000'—12,500'. Much to my surprise, these specimens show that, in spite of the nearness of the localities and the almost complete identity of external and cranial characters, the examples from Mt. Omi referred in my previous paper to U. soricipes, with a note on the discrepancy in the dental formula, belong to a distinct species altogether—that discrepancy being the distinguishing characteristic. For these two specimens, like that figured by Milne-Edwards and another one from Pére David’s series kindly lent me. by Prof. 'Trouessart, have no trace either of the minute p* or 1,, both present in the Omi species, nor any space in which they could have stood. We must therefore accept the formula given by Milne-Edwards as correct, and assign these examples to his species. This being the case, the Omi animal, with a constantly different formula, will need not only description as a new species, but the formation of a special genus for its reception. And, furthermore, a single example of the group from Chin-fu- san proves to have yet another formula, the small upper premolar being present, and indeed better developed than in the Omi form, the additional lower incisor is absent, while, alone in the group, a p, 1s present. The three animals may be briefly diagnosed as follows :— URopsILus. Teeth aX 2 = 34, neither p’, p,, nor i, present, the adult formula being therefore Lia a) I LO. & ee . ae ei ae eee ba Bee U. soricipes. Size fairly large. Colour near “ sepia ”; underside of tail lighter than upper. (Winter specimens only seen.) Nasinuus Thos. Teeth = x 2 = 38; p’ and p, present; no i, (detailed formula below). Type. . gracilis. Proc. Zoou. Soc.—1912, No, IX. !) 130 MR. OLDFIELD THOMAS ON RuyncHonax Thos. Teeth + x 2=38; p* andi, present; no p,. Complete dental formula as follows :— (alee 2 SE a Cale Oh asia (ert a NK aac) (ne | DNS Bel Lee a8 ee Pr Sos es dh Co i eames one | Slee tg «%3 Urea i Ce a Type :—RHYNCHONAX ANDERSONI. Uropsilus soricipes Thos. P. ZS. 1911, p. 163, nee M.-Edw. R. andersoni Thos. Abstr. P. Z.8. 1911, p. 49 (Oct. 31). Size comparatively large. Colour dark, approaching “ clove- brown,” the lighter specimens near ‘“ bistre.” Under surface dark slaty. Tail scaly, almost naked, scarcely lighter below than above (summer specimens only seen). Teeth described /. ¢., but the dental formula there given proves to be incorrect and should be as above. Dimensions of the type, measured in the flesh :— Head and body 70mm. ; tail 67; hind foot 15-5. Skull: greatest length 21:7; basal length 17:5; zygomatic breadth 11-6; interorbital length 5°5 ; breadth of brain-case 11:3 ; upper tooth-series 9°7. Hab. Omi-san, Omi-hsien, 8. Sze-chwan, 9500", Type. Adult male. B.M. No. 11.2.1.25. Original number 2504, Collected 15 August, 1910. Nine specimens examined. In naming this final species after Mr. Malcolm Anderson, I would recall not only the wonderful success he has made of the whole expedition, but also the extent to which he has increased our material, and with it our knowledge, of this particular group of Mammals. Practically the whole of our magnificent series of Urotrichus was obtained by him, including the specimens on which three new subspecies were founded, all our Uropsilus, Rhynchonax, and Nasillus were sent by him, while even our examples of Dymecodon were obtained by a Japanese whom he had taught to collect. 7. NASILLUS GRACILIS. Rhos, Abstr As02 19 lileap. AON (Oct..3!). @, 2566. Mt. Chin-fu-san, near Nan-chwan, S.E. Sze-chwan. 4000’. 20 September, 1910. B.M. No. 11.9.1.13. Type. A comparatively small species, with peculiar dental formula. Size decidedly less than in the other species, the hind foot 1-2 mm. shorter, and the skull smaller in all dimensions. General colour above near “sepia,” very much as in Uvropsilus soricipes, Rhynchonax andersoni being darker, Under surface MAMMALS FROM WESTERN CHINA, eat slaty. Hands and feet pale brown. ‘Tail uniformly brown above and below. Skull shorter and decidedly narrower than in either of the other species ; the brain-case less expanded laterally. Dentition :— Mier eee te eat ee 1 Hoe arene? 10 ¢ iS ee et a gas oe Upper p* (the tooth which is absent in Uropsilus soricipes and minute in Rhynchonax andersoni) comparatively large, as large as the small anterior premolar in the horizontal area. Below there is no trace of a minute incisor (i,) behind the large anterior tooth, but, on the other hand, alone in the group, a p, is present behind the tooth wrongly taken in my previous paper for p,, but really p,; it is slightly smaller than the corresponding tooth in the upper jaw and is therefore the smallest tooth present in the animal. Dimensions of the type, measured in the flesh :-— Head and body 66 mm.; tail 55; hind foot 13:5; ear 9. Skull: greatest length 20°5; basai length 16°5; zygomatic breadth 10; interorbital breadth 5; breadth of brain-case 10 ; upper tooth-series 9:1. Hab. and Type as above. This delicate little species proves to be of much interest, as its peculiar dentition has caused the discovery of the error in the dental formula of Rhynchonaw (under the name of Urepsilus) previously published, and indicates that that animal has in the lower jaw the very unusual premolar formula 1. 2.0.4, a formula which in Uropsilus oceurs in the upper jaw as well, This being the case, it is natural to examine again the dentitions of the nearly allied Uvrotrichus, Dymecodon, and Neurotrichus, and after some consideration [ venture to put forward the following as their formule, modifying those I had previously published :— Urotrichus :— eee ee | Jay: ST aia cade ait palin Bi: Dymecodon :— pee 2 58 ih gy De py hs Neurotrichus :— Lees 1 OrGe O 4 Yeas 9 a = ———— eS ee ee eer ore M. > 3-39 * 36. o = It will be seen that, arguing from the analogy of the minute teeth of Rhynchonax, which are missing in Uropsilus, | suggest that it is the third lower incisor which is missing in Urotrichus, g* 32 MR. OLDFIELD THOMAS ON and that in all, when one premolar is absent, it is the third and not the second, whether above or below. Of course these formule are still merely provisional, and liable to modification when good examples of the respective milk- dentitions are available for examination. 8. SorEX CYLINDRICAUDA M.-Edw. @. 2672. Near Yuen-ching-hsien, Sze-chwan. 5200’. 9. SorEX WARDI FUMECLUS. Thos. Abstr. P. Z.S. 1911, p. 49 (Oct. 31). S. 2606, 2616, 2627, 2657. 2. 2638, 2656. Wei-choe, on Si-ho River, W. Sze-chwan. 6000'—-11,000'. Larger and darker-coloured than true wardi, the brain-case broader. Fur about 6 mm. in length (winter). General colour nearly the same brown as in S. bedfordie or a little greyer, decidedly darker than in S. wardi. Dark dorsal line well marked in all the specimens, rather more diffuse than in the other striped species, but this may be due to the greater length of the winter coat. Under surface markedly greyer than upper (‘‘ smoke- grey”), while in S. bedfordie there is little difference between the two. Skull, like that of S. wardi, at once distinguishable from that of S. bedfordie by its lower and less vaulted brain-case. From that of the type of S. wardi it is separated by the rather larger size and by the distinctly greater breadth of the low flat brain-case. Dimensions of the type, measured in the flesh :— Head and body 60 mm.; tail 60; hind foot 13; ear 8. Skull : condylo-basal length 18:1 ; condylo-incisive length 18:5 ; breadth across brain-case 8-4; upper tooth-series 8°1 ; height of brain-case from basion 4°6. Hab. as above. Type. Adult male. B.M. No. 11.9.8.17. Original number 2627. Collected 24 November, 1910. This little striped Shrew has a considerable resemblance to S. bedfordie, but its flattened skull indicates that it is really more allied to S. wardi, of which it may be considered a darker- coloured representative. 10. SoRICULUS IRENE. Thos. Abstr. P. Z.S. 1911, p. 49 (Oct. 31). 3. 2674. @. 2673. Yuen-ching-hsien, S.W. ‘Sze-chwan. 5200’. General characters of S. macrurus, but brain-case much lower. Size about as in S. macrurus. Fur soft and fine; hairs of back (winter) about 6-5 mm. in length; about 5°0 mm. in what I believe to be summer specimens of the same species. General colour above uniform slaty grey (grey no. 4); under surface paler, MAMMALS FROM WESTERN CHINA, 133 near smoke-grey. Hands and feet whitish, a httle darkening on the metatarsals. Tail long and slender, uniformly grey-brown above, whitish below. In the summer specimens the underside of the tail is scarcely lighter than the upper. Skull quite like that of S. macrurus, except that the brain-case is conspicuously lower, the height nearly a millimetre less, the length and width being about the same. Teeth rather more heavily pigmented. Dimensions of the type, measured in the flesh :— Head and body 60 mm.; tail 90; hind foot 16; ear 10:5. Skull : condylo-incisive length 17-8; condylo-basal length 17-2; greatest breadth 9; height of brain-case from basion 4°9; length of upper tooth-series 7-4. Hab. of type as above ; specimens from Mt. Omi believed to be the same. Type. Adult female. B.M. No. 11.9.8.22. Original number 2673. ‘ollected 13 January, 1911. The specimens from Mt. Omi collected in August, 1910, are darker-coloured and their tails are scarcely lighter below, but they agree with the Yuen-ching examples in all other characters, and it seems probable that their differences are merely seasonal. They were formerly identified by me with S. maerurus of Darjiling, their distinctive character, the much lower brain-case, not becoming evident until the arrival of the present additional material, 11. CHopsicoa HypstBiA de Wint. @. 2604, 2642. Wei-choe, on Si-ho River, W. Sze-chwan. 5900'—7000'. These Shrews, collected in mid-winter, bear the same relation in colour to de Winton’s type that the winter specimens of Sori- culus irene do to those which I consider to be summer skins of the same animal, their grey being similarly paler and their tails more whitish. The type locality is by no means distant, nor is that of Ch. berezowskii, which, as previously stated, I believe to be of the same species. : The skulls of these specimens, however, being perfect, indicate that the Chodsiyoa previously obtained by Mr. Anderson in Chih-li, and assigned to Ch. hypsibia, must be separated speci- fically. It may be called CHODSIGOA LARVARUM. Thos. Abstr. P. Z. 8. 1911, p. 49 (Oct. 31). General characters of Ch. hypsibia, brain-case narrower and less flattened. Fur close and fine; hairs of back about 3°8 mm. in length. General colour above ‘ mouse-grey,” rather lighter, apparently “ smoke-grey ” below. Hands and feet whitish, Toil brown above, dull whitish brown below. 134 MR. OLDFIELD THOMAS ON Skull, although showing the peculiar flattening and concavity of the upper profile-line characteristic of the genus, not so extreme as that of Ch. hypsibia, the top of the brain-case fairly vaulted, and the sides not splayed out. Teeth quite as in Ch. hypsibia. Dimensions of the type, measured in the flesh :— Head and body 68 mm.; teil 50; hind foot 14; ear 8°5. Skull: condylo-incisive length 19:8 ; condylo-basal length 18°8 ; greatest breadth across brain-case 8°8; height of brain-case from basion 5; upper tooth-series 8°6. Hab. Traperial tombs, 65 miles E. ef Peking, Chih-li. 1000". Type. Adult female. B.M. No. 8.8.7.21. Original number 1559. Collected 25 September, 1907, by M. P. Anderson. Two specimens. 12. BLARINELLA QUADRATICAUDA M.-Edw. 9.2567. Near Nan-chwan, S.E. Sze-chwan. 4000’. 13, CrocriDURA ATTENUATA M.-Edw. @. 2565, 2572, 2573. Chin-fu-san, near Nan-chwan, 8.E. Sze-chwan. 4000’. 3g. 2575, 2581. @. 2576. Mts. 50 miles N.E. of Chung-king. 3000!. 14. AnouRosoREX squamipEs M.-Edw. @. 2570, 2574. Chin-fu-san, nedr Nan-chwan, 8.E. Sze- echwan. 4000’. Q. 2577, 2582. Mts. 50 miles N.E. of Chung-king. 3000’. 3d. 2675. Near Yuen-ching-hsien, W. Sze-chwan. 3. 2693, 2697, 2698, 2708. 2. 2707. 21 miles N.E. of Chao-tung-fu, Yunnan. 5800’. 15. Arcronyx opscurus M.-Edw. . 2651, 2662, 2663. Wei-choe, Si-ho R., W. Sze-chwan. 16. ScruRUS CASTANEOVENTRIS BONHOTEI Robinson & Wrought. | 9. 2676. Yuen-ching-hsien, S.W. of Ya-chow, Sze-chwan. 3000’. @. 2679. Ning-yuen-fu, 8. of Fu-lin, S.W. Sze-chwan. This subspecies has only been recently distinguished on the basis of Sze-chwan specimens jpuesene ed to the Museum by Mr. F. W. Styan. “ A forest-loving species; rare. ”__ ME. BEA, 17. SCIUROTAMIAS DAVIDIANUS CONSOBRINUS M.-Edw. 2. 2669. Wen-chwan-hsien, Si-ho R., Sze-chwan. 6000’. 4 MAMMALS FROM WESTERN CHINA, 135 18, Epimys numiiiatrus M.-Edw, 2. 2701. 21 miles E. of Chao-tung-fu, N. Yunnan. 5800’. This is an interesting animal as being a wild species closely allied to the ubiquitous pest, /. norvegicus, from which it chiefly differs by its smaller size. The flesh-measurements of Mr, An- derson’s specimens are as follows :—Head and body 160 mm. ; tail 130; hind foot 29; ear 17. Milne-Edwards’s J/us plumbeus appears to be the young of the same form, and it is also probable that his J/. owang-thome is not distinguishable from it. 19. Eetys conructanus M.-Edw. 3. 2568, 2569 (young). Chin-fu-san, near Nan-chwan, S.E. Sze-chwan. 4000’ (September). 3. 2583. 2. 2584 (young). Hwa-yin-san, 50 miles N.E. of Chung-king. 4000" (October). dg. 2594, 2600, 2602, 2603, 2641, 2643, 2658. 92. 2599, 2659. Wei-choe, on Si-ho R., W. Sze-chwan. —5900'—7000' (November—December). 3. 2682. 21 miles E. of Chao-tung-fu, Yunnan (March). The September and October specimens are distinctly spinous, the others quite soft-furred. 20, APODEMUS CHEVRIERI M.-Edw. 3. 2595, 2596, 2608. Wei-choe, Si-ho R., W. Sze-chwan. 5900'—7000'. db. 2680, 2681, 2682, 2683, 2688, 2689, 2691. 2. 2686, 2687, 2690. 30 miles 8.E. of Ning-yuen-fu, 8. Sze-chwan. 4500’. Be enlo. ai2e, ©, 2112, 2hloe 2pli, ates, 2024, 2727. Chao-tung-fu, N. Yunnan. 6400’. A. agrarius group. ‘Tail and ears comparatively short. M? without antero-external secondary cusp. M®* with only two internal projections. On finding both this species and the next in considerable numbers in the Sze-chwan collection, I have thought it advisable to verify the determination of Milne-Edwards’s Mus chevrieri, which, thanks to the kindness of Prof. Trouessart, I have now been able to do. To my great regret I find that my suspicions about the determination were justified, and that, instead of being the common and widely spread species allied to A. speciosus, as has been supposed, chevrieri is the rarer shorter-tailed form only recently sent us by Messrs. Anderson and Fergusson, the mouse I described as A. fergussoni being the same species, though perhaps subspecifically separable. Fortunately, like as the two species are externally, the determi- nation of specimens is easy enough by the dental characters given above, characters which show clearly in Milne- Edwards’s type, although the teeth are worn down. 136 MR. OLDFIELD THOMAS ON In all papers previous to this therefore* the name chevriert must be entirely withdrawn from the member of the speciosus group to which it has been wrongly attached. With regard to fergussoni, more material from Kan-su is needed before its characters can be elucidated ; but there is some evidence that the northern specimens of chevrieri, e. g. those from Wei-choe, have less fulvous suffusion on the hinder back than the southern ones, the type of fergussoni being completely without it. For the present, therefore, we may provisionally call the Kan-su form Apodemus chevrieri fergussoni, with the Wei-choe specimens as connecting intermediates. 21. APODEMUS SPECIOSUS PENINSUL& Thos. 3g. 2578, 2580. 9. 2579. Hwa-yin-san, 50 miles N.E. of Chung-king. 3000’. a. 2598, 92647, 2649) 2652, 26538012661.) 2. 2593" 2507, 2601, 2644, 2645, 2646, 2648, 2650, 2655, 2660. Wei-choe, Si-ho R., W. Sze-chwan. 5900'-7500'. A. speciosus group. ‘Tail and ears comparatively long. Molars more complicated; m? with antero-external secondary cusp; m* with three internal projections. 22, APODEMUS SPECIOSUS ORESTES. Nos, Aas, 12/4, So WOU, tos AD (Certs sill), A. s. chevrieri M.-Edw., Thos. P.Z.S. 1911, p. 172 (in part.). 3. 2610, 2622, 2624, 2636, 2654. 9. 2623, 2625, 2626, 2635. Wei-choe, R. Si-ho. 7000'-12,000'. As explained above, the common long-tailed Field-mouse of Sze- chwan proves to have no claim to the name chevriert, hitherto supposed to be applicable to it, and we have now to consider what it should be called. On laying out again the fine series received from Mr. Anderson, we find, to start with, that the specimens from Mt. Omi are -~ uniformly dark-coloured and clearly form a race distinct from the pale 4. s. peninsularis. This may be called A. 8. ORESTES. Size about as in A. s. peninsule or rather larger. Tail longer than head and body. Lars of medium size. Colour very dark, the back (im summer specimens) slightly more rufous than Ridgway’s “sepia.” Under surface grey no. 7. Skull slenderly built, of medium size. Dimensions, taken in the flesh :— Extremes Type. of Omi series. Hlendanid jue cytee- nase eae 93mm. 85 — 98mm. etl) ee LR ee. ae ae Ion, 102 -125 ,, itlanid hoot! vase. wek 2 eae 24 ,, 22°5— 25 ,, UE As Fea RAR CMO Fora te R 16 15:5-— 18 7 9 * From Barrett-Hamilton, P. Z.S. 1900, p. 418 onwards. MAMMALS FROM WESTERN CHINA. 37 Skull: greatest length 27°5 mm. ; condylo-incisive length 24°8 ; interorbital breadth 4:7; palatilar length 11°38; palatal fora- mina 5:7; upper molar series 4-2. Typical locality. Mt. Oi, W. Sze-chwan. 6000'-10,000'. Type. Adult male. B.M. No. 11.2.1.170. Original number 2535. Collected 18 August, 1910. This subspecies differs from peninsule by its darker colour and from the W. Fokien draco B.-Ham. by its larger size, longer tail, and less rufous tone. The Wei-choe series of the present collection contains examples agreeing with peninsule and others with orestes, and on exami- nation it proves that all of the latter are from altitudes above 7000', while all of the former are below that height. On the other hand, on Mt. Omi those from 6000' are of quite the same colour as those from 9000’, so that it cannot be said that the darker colour is a direct result of the altitude. 23. APODEMUS SPECIOSUS LATRONUM. Thos. Abstr. P.Z.8. 1911, p. 49 (Oct. 31). go. 2726, 2728. Chao-tung-fu, Yunnan. 6400’. (Series from Ta-tsien-lu previously enumerated.) A large form, with large ears and comparatively short tail. Size decidedly larger than in A. s. orestes. General colour above near “ broccoli-brown ”; under surface grey no. 7, the hairs slaty basally, whitish terminally. Ears very large, their visible surfaces black. Hands and feet white. Tail ranging from a little shorter to a little longer than the head and body, blackish above, white below. Skull conspicuously larger than in the other W. Chinese forms, as large as in true Japanese speciosus. Dimensions :— Extremes of Type. Ta-tsien-lu series. Wead and body :.5..--+=5- 107 mm. 95-108 mm. I Tl Seattle cera TOUTS LOO] 3 EMO MOOh Stott cies oss acess 253 24- 26 ,, | rig leemtetas eek sit enaeeg teeing ay 18- 20 ,, Skull: greatest length 29°6 mm. ; condylo-incisive length 26°6 ; interorbital breadth 4:3; palatilar length 12°8 ; palatal foramina 6:1; upper molar series 4°6. Typical locality. Ta-tsien-lu, W. Sze-chwan. 9000’, Type. Adult male. B.M. No, 11.2.1.156. Original number 2377. Collected 30 June, 1910. This distinct large-eared form would seem to range over the mountainous country to the west and south of the area inhabited by A. s. orestes. 24, Micromys pyemaus M.-Edw. 3. 2684, 2685. 30 miles 8.E. of Ning-yuen-fu, $.W. Sze- chwan. 4500’, 138 MR. OLDFIELD THOMAS ON 25. MIcROTUS MILLICENS. hos: Abstr PoZe Ss. 191 tip. 491(@cta 2). 3. 2613, 2614, 2615, 2621, 2639. 9. 2632, 2640. Wei- choe, on Si-ho R., W. Sze-chwan. 12,000'-12,500’. A greyish species with a delicate flattened skull, long tail, and extra angle on m°. Size medium, about as in J/. irene. Fur long, soft, and loose ; hairs of back (in winter pelage) about 12 mim. in length. General colour above rather darker than ‘ hair-brown,” passing into ‘“*smoke-grey ” below. Hars scarcely projecting above the fur, well-haired, greyish brown. Head and feet glossy greyish white, varying to greyish brown ; soles with 6 pads. Tail comparatively long, well-haired, grey-brown above, whitish below. Mammz 2—2=8. Skull rather hghtly built, with a long flattened oval brain-case without marked ridges or angles. Upper profile-line flat or even slightly concave at a point above m*. Rostrum of medium length, narrow. Interorbital region smooth, not ridged, flat- tened above. Angles of brain-case scarcely perceptible. Posterior palate normal, the lateral pits of medium depth. Incisors rather thrown forward. Molars narrow. M!' with the usual five spaces, all separated, a scarcely perceptible trace of a supplementary postero-internal projection. M? with a large supplementary postero-internal salient angle, making three angles on the inner side. M?* narrow, with the usual transverse first space, the second and third small, united to each other, and a posterior U ; three inner and three outer salient angles (the whole somewhat as in Blasius’s figure 221 *, except that the anterior transverse lobe is narrower, and the second and third spaces are united). M, with a large posterior transverse lobe, four lateral closed triangles in front of it, and a fifth united to the anterior trefoil, there being in all five inner and four outer salient angles (near fig. 193 of Blasius, if the first lateral closed triangle were open to the anterior trefoil). M, with the anterior two of the usual five spaces united to each other; three inner and three outer angles. In short, the most salient features of the dentition are the development of the extra postero-internal angle on m” and the junction of the second and third spaces of m* and first and second of m,,. Dimensions of the type, measured in the flesh :-— Head and body 90 mm.; tail 53; hind foot 18-5; ear 14. Skull : condylo-basal length 24°3 ; condylo-incisive length 24°6 ; zygomatic breadth 14:2; nasals 6:7; interorbital breadth 4:2 ; brain-case, length 12:5, breadth 11°5, height including bulle 9, height of supraorbital edge above root of m* 6-9; palatilar length 12:5; palatal foramina 4:8 ; upper molar series (crowns) 5:6. Hab. as above. * J. H. Blasius, Naturg. der Sdugethiere Deutschlands, 1857. MAMMALS FROM WESTERN CHINA, 139 Type. Adult male. B.M. No. 11.9.8.105. Original number 2615. Collected 20 November, 1910. This striking species, from the considerable altitude of 12,000’, is readily recognizable by its smooth flattened skull and long tail, the latter character separating it at once from J/. irene, to which alone of the Chinese species hitherto described it has any resemblance. In its possession of an extra angle on m’* it has a curious like- ness to many of the species of Hothenomys and Caryomys, this character in true Microfus being only hitherto known in M. agrestis L. and sikimensis Hodgs. 26. Mricrorus (EoTHENOMYS) MELANOGASTER ELEUSIS. Thos. Abstr. P. Z.S. 1911, p. 50 (Oct. 31). 3. 2694, 2695, 2696, 2700, 27038, 2704, 2709, 2710, 2711. @. 2699, 2702, 2705, 2706. 21 miles east of Chao-tung-fu, N. Yunnan. 5800’. [?¢d. 2571. Chin-fu-san, near Nan-schwan, 8.E. Sze-chwan. 4000’. | Longer-tailed than true melanogaster, with more complicated m’. General characters quite as in true melanogaster, though the colour may average slightly more greyish brown. Head and feet dark. Tail decidedly longer than in melanogaster, the shortest measured 43 mm., the majority about 46 or 48, and the longest 55; on the other hand, in a number of melanogaster the majority are 34-36, a single isolated example 43. Skull and teeth asin melanogaster, except that m’ is in nearly all cases more complicated, the posterior U-shaped lobe being rather a C, so that there are four inner salient angles instead of three. Dimensions of the type, measured in the flesh :— Head and body 98 mm. ; tail 55; hind foot 17; ear 11-5. Skull: condylo-incisive length 24°7 ; basilar length 22; zygo- matic breadth 15; nasals 7°4; interorbital breadth 4:2; breadth of brain-case 12°3; height of crown above alveolus of m* 7-7; palatilar length 11:8; palatal foramina 5:1; upper molar series (crowns) 5:6, Hab. East of Chao-tung-fu, N. Yunnan. 5800’, Type. Adult male. B.M. No. 11.9.8.111. Original number 2696. Collected 13 March, 1911. The Chin-fu-san specimen is a little indeterminate in character, the teeth of the two sides not being quite alike. 27. Microrus (KoTHENoMys) OLITOR. Thos. Abstr, P.Z. S.,1911, p. 50 (Oct. 31). Hamdten 2.2714, 2716, 2719, 2720) 2721, 2725... Chac- tung-fu, Yunnan. 6700’. A short-tailed sepia-brown Lothenomys without supplementary projection on in’, 140 MR. OLDFIELD THOMAS ON Size rather smaller than in J/. (Z.) melanogaster. General colour a Jess warm brown than in that animal, the upper surface nearest to ‘‘sepia”; under surface dark slaty grey (rather more smoky than “grey no. 5”). Hands and feet brown, soles with 6 pads. Tail dark brown above, little lighter below. Skull rather smaller than that of J/. melanogaster, but similar to it in general form ; the bulle not quite so large. Teeth agreeing with those of melanogaster in the junction to each other of nearly all the opposite spaces of the teeth, and therefore equally differing from the members, now four in number, of the subgenus Caryomys. But they are readily distinguished by the fact that m* has not got the characteristic supplementary postero-internal salient projection occurring in both m' and m* of melanogaster, and here present of full size in m*; as a result, there are three internal angles on both these teeth. M* more complicated than in melanogaster, with four salient angles on each side; it consists of three separated dentine spaces, the first with one inner and two outer angles, the middle one with one external and one internal angle, and the posterior with two internal and one antero-external angle. Lower teeth essentially as in melano- gaster, the spaces all opposite and united. Dimensions of the type, measured in the flesh :— Head and body 82 mm.; tail 34; hind foot 16; ear 9. Skull: condylo-incisive length 24; zygomatic breadth 15-4; nasals 6°8; interorbital breadth 4; height of crown from alveolus of m* 7-5; breadth of brain-case 11; palatilar length 11-5 ; palatal foramina 4°7; upper molar series (crowns) 5:5. Hab. as above. Type. Adult female. B.M. No. 11.9.8.122. Original number 2714. Collected 19 March, 1911. The dentition of this Vole is interesting, as it conforms strictly to the Hothenomys as opposed to the Caryomys type, while pre- senting such differences from that of J/. (1.) melanogaster as readily to distinguish the two species. “Trapped in the open fields of the little cultivated plaim sur- rounding the city.”.—M. P. A. 28. Mrcrorus (CARYoMYS) ALCINOUS. Thos. Abstr. P. Z.S. 1911, p. 50 (Oct. 31). 3. 2609, 2611, 2612, 2617, 2618, 2620, 2628, 2629, 2630, 2631, 2633, 26384. 2. 2619. Wei-choe, Si-ho R., W. Sze-chwan. 8000'-12,000'. Essential characters as in J/. (C.) eva, but colour much darker. Proportions, skull, and teeth all about as in eva. Fur long and soft; hairs of back about 9-10 mm. in length (winter). General colour above uniform dark bistre-brown, conspicuously different from the pale brown J/. eva; under surface dark smoky grey, decidedly darker than Ridgway’s ‘“smoke-grey.” Ears about as long as the fur, their backs with some whitish MAMMALS FROM WESTERN CHINA. 141 hairs on them, making an inconspicuous grey patch. Hands and feet dark brown. ‘Tail as long as in JZ, eva, blackish above, little lighter below. Skull apparently very much as in MZ. eva, though the bull are perhaps a little smaller. Dimensions of the type, measured in the flesh :— Head and body 90 mm. ; tail 56; hind foot 17; ear 11:5. Skull: greatest length 24; condylo-incisive length 23:8 ; zygo- matic breadth 14; nasals 7; interorbital breadth 4:3; breadth of brain-case 11°3; height of crown from alveolus of m* 7:1 ; palatilar length 11:2; palatal foramina 5; upper molar series (crowns) 5:7. Hab. as above. Type. Adult male. B.M. No. 11.9.8.1386. Original number 2631. Collected 24 November, 1910. The close agreement of this species with JM. (C.) eva in its proportions, notably in the unusually long tail and in its skull and dentition, is remarkable, as in its colour it is so entirely different that one would have expected to find distinguishing characters in other respects. 29. GAPRICORNIS MILNE-EDWARDST David. ©. 2667. Wen-chwan-hsien, Si-ho R., W. Sze-chwan. “Tnhabits the forests and cliffs at altitudes above 6000’. 1t is not so common as Vemorhedus cinereus. ‘* Chinese name ‘ Ngai-lii’? = Cliff Donkey, probably so called because of the long ears.”— M. P. A. 30. NA&MORHEDUS CINEREUS M.-Edw. 3. 2665, 2666. 9. 2664, 2671 (imm.). Wen-chwan-hsien, Si-ho R., W. Sze-chwan. 6000'—7000’. 31. ELAPHODUS CEPHALOPHUS M.-Edw. 3. 2668. Wen-chwan-hsien, Si-ho R., Sze-chwan. 8000. In the dark winter pelage, that figured by Milne-Edwards being in the rufous summer coat. “Very shy and retiring, but not really rare.”—M. P. A. 32. Moscuus siFanicus Buchn. 3. 2670 (imm.). Wen-chwan-hsien, Si-ho R., W. 8ze-chwan, 142 MR. R. I. POCOCK ON ELEPHANT-SHREWS. EXHIBITIONS AND NOTICES. November 21, 1911. S. F. Harmer, Esq., M.A., Se.D., F.R.S., Vice-President, in the Chair. Tue Secretary read the following report on the additions made to the Society’s Menagerie during the month of October 1911 :-— The number of registered additions to the Society’s Menagerie during the month of October last was 287. Of these 141 were acquired by presentation, 42 by purchase, 34 were received on deposit, 28 in exchange, and 42 were born in the Gardens. The number of departures during the same period, by deaths and removals, was 391. Amongst the additions special attention may be directed to :— 1 Budgett’s Cercopitheque (Cercopithecus tantalus budgetti), 2 Matschie’s Guerezas (Colobus matschiei), and 1 Shari River Hunting-Dog (Lycaon pictus sharicus), new to the Collection, from the Northern Congo, deposited on October 12th. 1 Duke of Bedford’s Wapiti (Cervus xanthopygius) 3, from Manchuria, deposited on October 9th. 1 Waterhouse’s Genet (Genetta poénsis), from 8. Nigeria, new to the Collection, presented by W. A. Lambourne, Esq., on October Ist. 1 Indian Redstart (Ruticilla rufiventris), new to the Collection, received in exchange on October 25th. 3 Myrtle Warblers (Dendraca coronata), new to the Col- lection, from North America, presented by HE. Hollman, Esq., on October 25th. 4 Peale’s Parrot-Finches (Zrythrura pealei), from the Fiji Tslands, presented by Dr. Philip H. Bahr, F.Z.S., on October 19th. 1 Rainbow-Bunting (Cyanospiza leclancheri), from. Western Mexico, new to the Collection, received in exchange on October 6th. 1 Malayan Wrinkled Hornbill (/hytidoceros wndulatus), received in exchange on October 6th. 2 Ring-necked Teal (Netiiwn torquatum), from South America, new to the Collection, received in exchange on October 20th. Mr. R. I. Pocock, F.R.S., F.L.8., F.Z.S., Superintendent of the Gardens, exhibited a living specimen of the Common Elephant- Shrew (Macroscelides proboscideus) (text-fig. 16), which had been captured at Tuin in Bushmanland and presented to the Society by Capt. H. A. P. Littledale, who sent at the same time a second example of the same species, an example of the Rock Elephant-Shrew (Hlephantulus rupestris) (text-fig. 17), also from MR. R. I, POCOCK ON ELEPHANT-SHREWS. 143 Bushmanland, and a number of small rodents, most of which belonged to species new to the Society’s list. After drawing attention to certain interesting morphological points connected with the group of Insectivora to which Elephant-Shrews belong, and remarking that the Society had never previously exhibited Text-fig. 16. Common Elephant-Shrew (Macroseelides proboscideus). Text-fig. 17. Rock Elephant-Shrew (ZJephantulus rupestris). specimens of the family Macroscelididee, Ma. Pocock pointed out that in their general appearance and behaviour these animals much more closely resembled Mouse-like rodents than Shrews, on account of the length and texture of the fur, the prominence and size of their staring eyes and of the pinna of the ear, the 144 MR. GEOFFREY SMITH ON THE only feature that recalled the Shrew being the long, cylindrical, twitching snout. They were also quite like rodents in their quadrupedal gait, the ground being traversed by the ordinary running action or by lightning-like leaps from point to point. They did not raise their fore-quarters from the ground more frequently than is the custom with typical rodents, and were never seen to hop on the hind legs alone, like Jerboas and Kangaroos, as they have been declared to do in some natural histories. In appearance the two examples of MJacroscelides proboscidews differed considerably from the one representative of Hlephantulus rupestris. In the former the eyes were smaller and the ears more widely separated and more concealed in the hair of the sides of the head. In Elephantulus rupestris there was a conspicuous light ring round the large eye, the ears were more erect, and separated by a much narrower space on the top of the head. It was noticeable, too, that, whereas the Rock Elephant-Shrew lay hidden beneath a heap of hay during the daytime, the two Common Hlephant-Shrews preferred to huddle together in the open part of the cage, evincing a dislike to push beneath the hay and refusing to remain under it when it was placed over them. The differences between the living animals, indeed, quite bore out the view, based upon the structure of the skull, that the two species belonged to different genera. PAPERS. 10. The Freshwater Crayfishes of Australia. By Grorrrey Sura, M.A., Fellow of New College, Oxford”. [Received October 20, 1911: Read November 21, 1911. ] (Plates XIV.-XXVII.7 and Text-figure 18.) 1. Introduction. The study of Freshwater Crayfishes has been distinguished by the labours of Huxley; the detailed work of Ortman and Faxon has made us acquainted with the North-American species of Astacus and Cambarus, and Faxon has reduced the South- American genus Parastacus and the New Zealand Paranephrops to order, but what Huxley wrote in 1879 concerning the Australian Orayfishes, ‘‘ that their nomenclature requires thorough revision,” is almost as true to-day as thirty years ago. The following memoir does not pretend to be an exhaustive monograph of the anatomy or of the systematic classification of the Australian Crayfishes, but by publishing the series of accurate * Communicated by the Secretary. + For explanation of the Plates see pp. 170-171. PeeZeon lO laneee | ASTACOPSIS FRANKLINII. dy, ALV. Be 4 ole el ey, ASTACOPSIS FRANKLINII. a ot PaeG.o. LOA, el ASIACOPSIS SERRATUS: 2 Bee 2, 5. Ol. Pl, i Y | Cn Mp. ben nn — = —— arn yey ECigaa ae | Sllebinn yee Ble [c, a eeCUL Ey Wy \eeniaes Vey! Keilor. gas: | m Spee ef elaielSiss a See 42/5 | AXala\s\< "<0)) NSU 8 SEeggeeloltes ei) 0] 8) Slelery: | et te i wil OVE EG pyc e. F2/0y-Y a; 4 alex —— A.E.C. del. West, Newman lith. ALIMENTARY CANAL OF BACILLUS ROSSI. ‘ PZ.5. Leta Pl Axx. RV ay, Ai QO OD Iss Sr ‘ A.E.C. del. West, Newman lith. Be ALIMENTARY CANAL OF BACILLUS ROSSII. THE STICK-INSECT. Ng the Old World, and it has a wide distribution, occurring in Europe, Africa, East Indies, Ceylon, Java, China, Sandwich Islands, Australia, Island of Hamoa, and New Zealand.” In the course of the present year several English collectors have had in their possession specimens which were observed to deposit their ova during the months of February, March, and April, and the hatching of the ova began in the latter part of June. It is highly probable that this insect, alien to the British fauna, made its entrance into this country along with fruit-cargoes and nursery-stock imported from France. ‘There is not much chance of its becoming established here since, being accustomed to mild temperatures, it fares rather badly under the changeable conditions of the English climate. In captivity they require close attention; but by supplying them regularly with fresh food-plants and by keeping the temperature of their surroundings at about average house-temperature they appear to thrive. Under these conditions they are quite healthy, and the mortality is very low. Note on Parthenogenesis, A very curious phenomenon in connection with the repro- duction of Bacillus rossii may be worthy of note. Although my specimens were in the third generation reckoning from the first generation in captivity, no male had been observed, and perhaps parthenogenesis had been the normal method of reproduction previous to this, as my observations were necessarily limited by the fact that I had no record of the generations preceding the first one in captivity. Von Baehr (1907) records that in 1903 he received specimens of B. rossii whi¢gh belonged at least to the seventh parthenogenetic generation, being descendants of a half- grown female captured in Dalmatia in 1896, But the latter, he says, may itself have arisen from an ovum parthenogenetically produced, so that in all probability it was not the first in the ancestral line to produce ova which had not been fertilised by the sperm. These facts seem to lend support to the supposition that the female of B. rossit can dispense with the GAR altogether and that virgin, rather than sexual reproduction is the normal method adopted by this insect of perpetuating its race. We cannot state with any degree of confidence why the insect has betaken itself to the parthenogenetic production of eggs, but that advantages accrue we are tolerably certain. In cases where, owing to some cause or other, there is a scarcity of males, the method would be a decided acquisition, since the great majority of the more prevalent females would stand a very poor chance of ever meeting a male and of the consequent enjoyment of sexual intercourse. I think that it is open to make the hypothesis that both sexes of B. rossii originally existed in equal numbers. Owing to some cause with which we are not acquainted, the males began to 174 MR. A. E. CAMERON ON diminish so that the dominant female, in order to safeguard the species against utter extirpation, began to reproduce partheno- genetically. We must understand that the process has been a very gradual one, proceeding slowly throughout several centuries, the male finally becoming almost extinct. Another interesting question intimately connected with the subject of parthenogenesis may be asked. Why does the female produce ova from which only females arise? While I offer no suggestion, I may be permitted to allude to the same phenomenon which occurs regularly in many of the Cynipide or Gall-fiies. The male of Cynips kollari, the maker of the marble-gall of the oak, has never been observed, although many entomologists have given this species their close attention, and it is now generally believed that it does not exist, but that parthenogenetic repro- duction is the only method of preserving the species. The following is quoted from Adler and Straton’s ‘ Alternating yenerations’ (Oxford, 1894). “Tt would appear that in Cynips kollari the sexual generation is wholly subordinated to the asexual, and in /thodites rose, which forms the pretty Bedeguar galls on the rose-tree, the process is still going on, and the males are becoming functionless and extinct. ... Lt is difficult to believe that the agamous (or asexual) can be the primitive form ; or that the perfectly formed sexual organs could have been evolved unless the sexual had been the earlier generation.” Alimentary Canal. While at the Royal College of Science, London, in the beginning of 1911, it was suggested to me that the alimentary canal of Bacillus rossti would repay careful observation. The material at hand I subsequently worked up in the Zoological Department of Manchester University, and I here take the opportunity of expressing my indebtedness to Professor Hickson as well as to Mr. Manean for many timely hints. In the Orthoptera viewed as a whole the alimentary canal shows a very uniform structure; but in the various families there are many secondary differences, sometimes even in the same family, necessitating special description. The gizzard is im- portant in the Orthoptera, and there are diverse degrees of complication in its chitinous armour. The intestinal cca vary ereatly in number, there being eight in Mantidw and Blattide, six in Acridiide, and one pair ot lateral ceca in Locustide and Gryllide. The diverse variations of structure in the gizzard, its different degrees of complexity added especially to the pre- senee or absence of intestinal ceca, suggested to Bordas (1897) a te] method of dividing the Orthoptera into two large groups : 1. The Acolotasia, or Orthoptera without intestinal caxea ; 2. The Colotasia, or Orthoptera with intestinal ceca more or less numerous, THE STICK-INSECT. 175 The Malpighian tubes in all Orthoptera except the Forficulide ave very numerous, and are generally grouped in six bundles opening at the summit of six tubercles, as in the Locustide and Blattide. In all the Gryllide, on the contrary, the Malpighian tubes are arranged in a single bundle opening into the dilated extremity of an unpaired excretory canal. Very characteristic is the presence of a “ciliated border ” (un revétement cilié) projecting from the cells of the mid-intestine and _ lateral appendages. The alimentary canal of B. resszi is divided into three parts, as in all arthropods. 1. Fore-gut, ectodermic, corresponding to the stomodeum, and comprising the mouth , pharynx, cesophagus, and crop (Pl. XX VIIT, fig. 1); the gizzard is ‘absent. a Mid-g ut, endodermic, corresponding to the mesenteron, beginning “posterior to the crop and ending at the insertion of the Malpighian tubes. The lateral ceca, ” generally developed from ie anterior part of the mid-gut, are rudimentary in B. rossii (fig. 3. tad gut, ectodermic, corresponding to the proctodeum, beginning at the i insertion of the Malpighian tubes and including small intestine and rectum (fig. 1). In many respects the alimentary canal is peculiar, and the main features which contribute to its uniqueness may be tabulated as follows :— 1. The rectilineal shape of the gut, there being no con- volutions of the posterior region (fig. 1). . The complete absence of the gizzard. . The rudimentary nature of the mid-gut digestive ceca (figs. 1 & 3, C.). 4. The presence of numerous peculiar conical tubular. organs on the posterior position of the mid-gut Cig. t,o ka.) In preparing sections for histological examination of the gut various stains were employed. Grenacher's hematoxylin was especially g good in the differentiation of chitin, while Heidenhain’s iron- -hematoxylin proved very effective where epithelium was concerned. Professor Hickson’s brazilin stain and borax carmine were also used to advantage. To get the best results the gut required rather careful tre atment, and in the matter of a fixing agent I found that Schaudinn’s fluid was all that could be desired, It is generally accepted that the mid-gut of insects is endo- dermic in its origin, but in the ease of B. rossii Heymons (1897) demonstrated that it was really ectodermic, being developed from two epithelial outgrowths of the stomodeum and _ proctodeum which surround the yolk and become united. This manner of formation, he maintains, may be found to hold good for all Phasmidee. oo bo 176 MR, A. E. CAMERON ON The fore-gut up to and including the crop is of rather simple structure. As a rule the histological structure of the insect alimentary canal is always the same: on a layer composed of muscular and connective tisssue there rests an epithelium which secretes a strong chitinous lining. This cuticle is raised into straight longitudinal ridges which bear numerous minute horny denticulations. The pharynx of B. rossi (fig. 1, Ph.) is very short and is lodged in the posterior cephalic region, the cesophagus (fig. 1, CH.) occupying the elongated prothorax and passing insensibly into the somewhat dilated crop (fig. 1, Cr.) in the region of the mesothorax. Lastly, the crop joins the mid-gut (fig. 1, Gm,) in the region of the metathorax, and, indeed, the internal wall of the crop is telescoped into the cavity of the mid-gut as a cone-shaped prolongation (Riissel), But in addition to what may be called the primary direct extension of the crop (Pl. XXIX. fig. 5, Ov, and Ov,) there is also a secondary indirect extension (fig. 5, Ov, and Ove,). The chitinogenous epithelial cells of the wall of the crop extend backward into the mid-gut for a short distance as far as the point A denoted in the figure. They then become folded back on themselves up to the point B, and turning once more form the long dorsal pro- longation which reaches a comparatively long way into the mid-gut. At C the cells are again reflected, and finally at D join with the larger epithelial cells of the mid-gut. The chitinous cuticle lining the prolongations is continuous with that of the crop, From fig. 5 it will be observed that the extensions are not symmetrical but are much more pronounced dorsally than ventrally. This un- symmetrical arrangement is known to occur only in the few Phasmids in which the alimentary canal has been investigated, and the exact reason of the greater development of the dorsal lamina is not known. In the larve of Chironomus the esophageal ~ telescoping is uniform and symmetrical, and I believe that this is the case with the majority of insects where the telescoping occurs. Heymons (1897) gives it as his opinion that the elongate dorsal lamina (Verschlussklappe) functions as a closing-valve, preventing the back-flow of digested food from the mid- to the fore-gut. But Sinéty (1901) does not agree with this interpre- tation, as he is convinced that if the direction of the food-current were to be reversed this flap would be overcome by the pressure. The bundles of circular muscle surrounding the anterior part of the mid-gut would be quite effective in checking the reversed food-current if any sueh occurred. The mid-gut of B, rossij is divided into two distinct parts, of which the anterior is characterised by very prominent transverse folds (P], XXVIII. fig, 1, Gm, ; fig. 3, Gm,; Pl. X XIX. fig. 5); while the posterior (fig. 1, Gm,), besides being narrower, is easily distinguished by the presence on its external walls of numerous (about 59) conical, tubular organs (fig, 1, Ta,), In all Orthoptera as before stated, except the Phasmide, the surface of the mid-intestine is enlarged by diverticula of various {THE STICK-INSECT. Wize shapes developed from the anterior end, eight long cylindrical ceca in Blattide and Mantide, two large rounded ceca in Locustide and Gryllide, or again six pouches in Acridiidee, which may be further provided with inferior appendages. In B. rossii these ceca (fig. 1, fig. 3, fig. 5, C.) exist merely as small lobes clustered together in small numbers and very rudimentary. These ceca must not be confused with the gland-like structures (fig. 1, Ta.) which occur just anterior to the Malpighian tubes. Indeed it is not definitely known whether the function of these latter so-called “ glands” is really glandular, secreting a digestive * juice which is poured into the intestine, or excretory, eliminating waste products like the Malpighian tubes. At their point of attachment to the gut these organs are pear-shaped, tapering abruptly into a small tubular thread, the calibre of which is about half the size of that of the Malpighian tubes amongst which they pass. Heymons (1897) has shown that in origin and morphology these tubular appendages bear a very clue resem- blance to the Malpighian tubes; but physiologically he regards the two sets of organs as differ ent, since they are dissimilar in their behaviour towards injections of coloured particles. Generally speaking, it was found that the tubular appendages were the less sensitive, but they may eliminate some substances quite as actively as the Malpighian tubes, as, for instance, Ehrlich blue. If thei function be excretory, it is less general than that of the ordinary organs of excretion. The internal wall of the mid-gut is a TEED of a layer of “ large cylindrical epithelial cells (Pl. XXX. fig. 5, E; fig. 6, E and E ,) provided with a “striated border ” (fig. 5 and fig. 6, Ch.) and further they are characterised by a continual secretion of globules of mucilage (fig. 5 and fig. 6, Mg.), which are deposited in the intestinal cavity. Cuénot (1895), amongst other authors, describes the presence of young cells in this epithelium undergoing mitotic division and gradually replacing the older cells, These are of the nature of small interstitial cells with rather dense, deep- staining nuclei; but I myself have not observed any mitotic figures in them. There is still dispute on the question of these so-called ‘ germinative-centres,” and many authors, notably Frenzel (1886) and Visart (1894), consider them as glandular crypts. There is no protective chitinous cuticle lining the internal walls of the mid-gut, but its place seems to be falen by a very slender peritrophic membrane (figs. 5 and 6, Mp.) which is quite detached from the epithelium. It takes its origin at the point where the fore-gut epithelium joins that of the mid- gut, and extends as far as the hind-gut, which it enters for a ‘short distance. Thus the food passes through the alimentary canal without the delicate epithelial cells running any risk of abrasion from jagged particles eaten by the insect in the course of its diet. This membrane (Trichter) is certainly not a prolongation of the chitinous cuticle of the crop, as Mecanikow and Schneider (1890) Proc, Zoou, Soc,.—1912, No, XII, 12 178 MR. A. E. CAMERON ON believed, but seems to be secreted by the most anterior epithelial cells of the mid-gut. The question may be asked: How does S. rossu assimilate its food? ‘This can only be explained by a knowledge of the laws of osmosis, so that the digestive juices secreted by the epithelium and the fluid juices which result from their action must pass through the membrane, the former to act on the food substances, the latter to be absorbed. Schaeider (1890) and Adlerz have observed the presence of a peritrophic membrane in diverse Orthoptera, Phyllodromia, Peri- planeta, Bacillus, Locusta, Forficula. ‘This has been verified by Cuénot (1895), who adds some details as regards its origin of which little is known. Plateau (1875), in his splendid work ‘ Recherches sur Jes phénomenes de la digestion chez les msectes,’ has shown that digestion first begins in the crop, where the alkaline or neutral secretion of the salivary glands acts on starchy substances, changing them to glucose. The processes of digestion are con- tinued in the mid-gut, the epithelium of which also secretes a fluid with alkaline or slightly acid properties which has the power of changing albuminoids into peptones and of emulsifying fats. Petrunkewitsch (1899) held that in certain Orthoptera the crop was the principal organ for the absorption of digested food, citing as his proof the presence of fat in the epithelial cells. But Sinéty (1901) demonstrated clearly that the fat globules here present are really elaborated by the epithelial cells from materials extracted from the blood, and thus the epithelium of the crop is functionally comparable to the fat-body. Again, many authors adopted the idea that owig to the shortness of the mid-gut supplementary absorption must be carried out in the crop (Plateau [1876] and Jousset de Bellesme in the Blattide), or even in the hind-gut (Plateau [1878] and Frenzel [1886]). But from all known laws of osmosis it is highly improbable that this can be the case, for the thick chitinous cuticle lining both crop and hind-gut is Impermeable to dissolved substances. Again, it is nothing short of absurd to suggest that absorption can go on below the point of insertion of the Malpighian tubes which mark the posterior limit of the mid-gut, and invariably pour their waste-products into the alimentary canal at this place. In #. rossi the Malpighian tubes: (Pl. XXVIII. fig. 1 and. Pl. XXX. fig. 7, Mt.) are very numerous and are disposed re- gularly in a circle round the anterior end of the hind-gut, into which they open in groups of three to six. These groups, occurring | to the number of 20 to 30, are equidistant from each other, and the tubes composing any one group fuse at the apex of a small conical tubercle which arises as an evagination from the gut and is traversed by a minute duct (fig. 7, Cd, and Cd,). The con-. stituent cells of the Malpighian tubes also possess the “ ciliated border” characteristic of the epithelial ceils of the mid-gut, but the “cilia” in both cases do not possess any power of motion even in an indifferent medium. It cannot be argued that the fact of the insect being dissected would cause the “cilia” to cease vibrating immediately, as the cilia on the gill-plates of THE STICK-INSEC'T. 179 Unio, the fresh-water mussel, continue their vigorous move- ment long after the removal of the gills from the animal, In conclusion I may state that the different authors who have investigated the matter refer to the “ciliated border” under various names, such as “striated plate ” “ciliated plate,” “ plate composed of free-filaments or rods,” “ brush-like border” (Hirchensaum of Frenzel); but all these terms convey to our minds exactly the same idea. The hind-gut, including the small intestine (Pl. XXVIII. fig 1, Is.) and rectum (fig. 1, R.), is, like the fore-gut, lined with chitin. In the small intestine I distinguish two regions—the anterior one broad, with small internal longitudinal folds, and the posterior narrow, the circumference of which is greatly lessened by the deep infolding of the epithelium, the lumen appearing only as six narrow bays. Just anterior to the narrowing a circular band of muscle surrounds the small intestine and by its contraction shuts off the anterior from the posterior region. A curious valvular apparatus (PI. XXX. fig. 9, F.) occurs at the anterior oritice of the rectum in the shape of six muscular pyramidal projections inserted by one of their surfaces in the internal wall of the gut, and with the surface adjacent to the rectum slightly hollowed out. The small intestine can be completely cut off from the rectum by a muscular band on the external wall, which when it contracts brings the six valves together so that the passage is completely closed. The rectum (fig. 1, R.) bears internally six longitudinal thicken- ings of large epithelial cells (Pl. XXX. fig. 8, KE.) which have a glandular function, and between the epithelial cells and the basement membrane (fig. 8, Mb.) there ramifies a system of trachee, suggesting a rather perfect aeration of rectal tissues. Musculature of the Alimentary Canal. As always in insects, the gut is provided with two sets of muscles, longitudinal and circular, which extend along its whole length. But in B. rossii there is a marked deficiency of longi- tudinal muscles in the region of the fore-gut, and their place seems to have been in great measure taken by six broad bands of short oblique fibres which belong morphologically to the circular system (PI. XXVIII. fig. 2, Mo.). On the mid-gut the bands of circular muscles are set wide apart, producing the characteristic furrowed appearance of this region of the intestine. The longitudinal muscles present some interesting peculiarities. They extend all along the intestine with the exception of the anterior part, as slender fibres equidistant from each other, and numérous branches are given off from the main strands. These branches may anastomose where they run close together, or they may taper off into extremely fine threads. The longitudinal muscles seem to play an important part in connection with the morphological significance of the pyriform organs of the posterior region of the mid-gut. he latter are observed to arise either in close proximity to one, or equidistant from two longitudinal i2* 180 MR. A. E. CAMERON ON muscles. In the first case a single branch is given off from the main fibre and may be traced to the surface of the pear-shaped dilatation ; in the second case two branch fibres may be supplied, one from each of the two nearest longitudinal muscles. Under a nerve stimulus these branches are said to be the mechanism whereby the mid-gut appendages are animated with a movement analogous to that observed in the case of the Malpighian tubes (Sinéty [1901)). In the anterior region of the mid-gut there is a distinct dorso- longitudinal furrow (Pl. XXVIII. fig. 1, F, and fig. 3, F,) in which numerous longitudinal muscles are congregated, and toa less extent the same phenomenon is observable in the ventro- longitudinal furrow. The fibres which are situated dorsally and laterally on the mid-gut are united into three, then into a single strand which proceeds anteriorly to its attachment in the pronotum. Those fibres lying ventrally are united into a somewhat more slender strand. As they pass backward to the hind-gut the longitudinal muscles become grouped into six strong bands applied symmetri- cally to the wall of the gut, and giving off distally cutaneous branches which proceed outwards. Summary. The alimentary canal of B. rossii presents us with much that is of interest. Its rectilineal shape is what we would naturally expect from the narrow elongated form of the insect. But the absence of a gizzard, together with the rudimentary digestive ceca and the presence of tubular filiform organs at once arrest attention. The anterior portion of the mid-gut is puckered owing to the isolation of the circular muscle-bundles. The Malpighian tubes are curiously grouped in bundles of from three to six, each bundle opening into the gut by a common duct. The small intestine is separated from the rectum by six powerful pyramidal valves. The internal wall of the crop telescopes into the lumen of the mid-gut, and the telescoped portion is reflected on itself in a curious manner. The fact that the males of B. rossii are disappearing points to parthenogenesis not being the primitive method of reproduction, but suggests that the species has become adapted to it through the failure of sexual reproduction, LITERATURE. 1841, Durour.—Recherches anatomiques et physiologiques sur les Orthopteres, les Hymenoptéres et les Névropteres. Mem. Ac. Se. Paris, t. viii. p. 265. 1858. Srropor.—Recherches sur les sécrétions chez les insectes. Ann. Sc. Nat. (4) t. x. p. 251. 1875. Puarrav.—Recherches sur les phénoménes de la digestion chez les insectes. Mém. Acad. Roy. Belgique, t. x1. lre partie. 1876. 1878. 1879. 1882, 1886. 1886, 1889. 1890. 1894. 1895. 1896. Teo. 1897. 1899. 1899. 1899. 1900. 1900. 1900. 1901. 1901. 1904, 1907. THE STICK-INSECT. 181 Puateau.—Note sur les phénoménes de la digestion chez la Blatte américaine. Bull. Acad. Roy. Belgique, (2) tai. p.. F206. ScurvpLer.—Beitriige zur Kenntniss der Malpighischen Gefiisse der Insekten. Zeits. fiir wiss. Zool., 30 Bad., p-. 087. Girarp.—Traité élémentaire d’Entomologie, vol. 1. Paris. VIALLANES.—Recherches sur l’histologie des insectes et sur les phénomeénes histologiques qui accompagnent le développement post-embryonnaire de ces animaux. Ann. Sc. Nat. Frenzev.—Kiniges iiber den Mitteldarm der Insekten sowie iiber Epithelregeneration. Arch. ftir mikr, Anat., 26 Bd., p. 229. Mratn and Denny.—The Structure and Life-History of the Cockroach. London. Scuirror.—Beitriige zur Histologie der Insekten. Zool. Jahrb. (Abth. fiir Anatomie), 3 Bd., p. 611. Scunemper._Ueber der Darmkanal der Arthropoden. Zool. Beitriige, Bd. 1. Visartr,—Contribuzione allo studio del tubo digerents degli Artropodi, Atti d. Soc. Toscana di Se, Natur., vol. xint,, p..20. Cutnor.—Etudes physiologiques sur les Orthopteres. Arch. de Biologie, t. xiv. Borpas.—Considérations générales sur l'appareil digestif des Phasmide. Bull. Mus. Paris. Borpas.—L’appareil digestif des Orthopteres. Ann. Se, Nat. t. v. Hrymons.— Ueber die Organisation und Entwickelung von Bacillus rossii Fabr. 8.B. Ak. Berlin. Curnor.—Sur la détermination du sexe chez les animaux. Bull. Se. France et Belgique, t. xxxil. Dominique. — Parthénogénése et thélytokie chez _ les Phasmides. Bull. Soc. Sc. Nat. Ouest Fr., t. xi. PerrunKewrtscu.—Zur Physiologie der Verdaming bei Periplaneta orientalis und Blatta germaniea. Zool. Anz. 1899, p. 137. Kuri. —Biologisches iiber Bacillus rossii. Ent. Zeitschr. nos. 16-17. Srvtry._Sur la parthénogénése des Phasmes. Bull. Soc. Ent. France, p. 194. Sintiry.—Les tubes de Malpighi chez les Phasmes, Bull. Soc. Ent. France, p. 350. Srviry,—Recherches sur la biologie et Vanatomie des Phasmes. L’Université de Paris. Cellule XTX. Goprrman.—Beitriige zur Kenntniss von Bacillus rossit. Arch, f. Entw.-Mech., Bd. xii. Hennecuy.—-Les Insectes. Paris. y. Baur—Zool. Jahrb. (Anat) vol, xxiv. 182 ON THE STICK-INSECT. EXPLANATION OF THE PLATES. Pruate XXVIII. Fig. 1. Alimentary canal of Bacillus rossii. Md., mandibles; Ph., pharynx ; Fig. 2 M., muscles of the pharynx; €., esophagus; Cr., crop; Gmyj, anterior region of the mid-gut; Gmg, posterior region of the mid-gut; F., dorso- longitudinal furrow in which several longitudinal muscles are congregated ; C., rudimentary ceca of the mid-gut; Ta., tubular appendages of the mid-gut with thei filiform prolongations; Mt., Malpighian tubes ; Is., small intestines; R., rectum, with the rectal longitudinal folds Rf. . Portion of the external wall of the crop. Mc., circular muscle; Mo., band of oblique muscle fibres, of which there are six, extending longitudinally along the cesophagus and crop, and displacing in great measure the ordinary longitudinal muscles ; Rme., circular muscles reflected to show one of the _bands of oblique fibres. Vig. 3. Crop and anterior part of the mid-gut. Cr., crop; Gn., ganglion ; Tr., traches ; Fig. 4 Gm., mid-gut; C., rudimentary ceca of the mid-gut; FI., longitudinal muscles grouped together in the dorso-longitudinal furrow; M1,, longi- tudinal muscles lying outside the furrow. PuatEe XXIX. . Transverse section of the crop. Mc., circular muscles; MI., longitudinal muscles; Pm., peritoneal membrane; E., epithelial cells which secrete the chitinous lining Ch. Fig. 5. Longitudinal section of the posterior region of the crop and anterior region of the mid-gut. Mc., circular muscles of the crop; C., rudimentary digestive ceca; Me., mucilaginous globules secreted by the epithelial cells of the ceca as also by those of the mid-gut. In the mid-gut these globules occupy the space between the epithelial layer and the peritrophie mem- brane. They are not included in the figure. M1., longitudinal muscles; Ch., chitinous lining of the erop secreted by the chitinogenous cells cc., extending with the “valvular” prolongation into the mid-gut; Mp., peri- trophic membrane; E., epithelium of the mid-gut with Cb., the ciliated border; Ov,, primary dorsal cesophageal “ valve” with the corresponding ventral small “valve ” Ovya. Fig. 6. Transverse section of the anterior region of the mid-gut. E., epithelium; Cb., ciliated border; Ey, epithelium of an adjacent fold which has also been cut through; Ml; and Mls, the longitudinal muscles of the dorsal and ventral longitudinal grooves of the mid-gut; Mc., circular muscles; Mp., peritrophic membrane; Pm., peritoneal membrane; Mg., globules of mucilaginons secretion. PratE XXX. Fig. 7. Transverse section through the junction of mid- and hind-guts. E., epithe- lium; .Ml., longitudinal muscles; Pm., peritoneal membrane; Mp., peritrophic membrane; Ch., chitious lining of the hind-gut; Mt., Mal- pighian tubes; Cd) and Cds, common ducts of several Malpighian tubes. Fig. 8. Transverse section of the rectum. E., band of large epithelial cells, of which there are six; between each two bands there is a non-epitheliated interspace I, where the chitmous intima Ch. becomes corrugated and is ~~usely applied to the basement-membrane Mb.; Tr., trachea; M., muscular layer. Fig. 9. Section through small intestine at the orifice of the rectum. F., one of the six projections or valves which shut off the small intestine from the rectum ; H., epithelium secreting the chitinous intima Ch.; Mce., circular muscle; M1., longitudinal muscle; Tr., trachea. IP (Aa) LO PIZeeae Sr ATL.Searle delet hth. Huth, imp. NEW AFRICAN TERRESTRIAL AND FLUVIATILE SHELLS. Pea Ss OZ eos 4. AH.Searle delet lith. NEW AFRICAN TERRESTRIAL AND FLUVIATILE SHELLS. ON NEW 'FERRESTRIAL AND FLUVIATILE SHELLS, 183 12. Diagnoses of new Species of Terrestrial and Fluviatile Shells from British and German East Africa, with the Description of a new Genus (Mussora) from the Eusso Nyiro River, B.E. Africa. By H. B. Preston, ¥.Z.8. [Received September 27, 1911 : Read November 21, 1911. | (Plates XXXI. & XXXIL*) The species described in the present paper were all, with one exception, collected by Mr. Robin Kemp during his more recent travels in British East Africa. As they represent only a very small portion of the large number of species sent home by Mr. Kemp, it will be readily seen what a vast field there is for investigation in the mollusean fauna of this almost hitherto unknown concho- logical province. ENNEA MicrostriavA, sp. n. (PI. XXXI. fig. 7.) Shell scarcely rimate, ovate, edentulate, moderately thin, cream- coloured; whorls 6, the first four small, regularly increasing, the fifth large in proportion, gibbous, the sixth proportionately longer though not quite so broad, marked especially on the fifth whorl with oblique, distant, regular growth-lines, and sculptured with closely-set, microscopic, serateh-like strie ; suture impressed, closely and rather finely crenellate below ; umbilical area represented by a somewhat broad depression, sloping to an extremely narrow, elongate, and shallow fissure ; columella rather vertically descending in a gentle curve ; labrum narrowly out- wardly expanded, very slightly reflexed ; aperture subquadrate. Alt. 7°5, diam. maj. 5 mm. Aperture: alt. 2, diam. 2 mm. Hab. Dar-es-Salaam, German East Africa (Connolly). NATALINA PERMEMBRANACEA, sp.n, (PI. XXXI. figs. 20, 204, 20 b.) Shell perforate, suborbicular, with almost planulate spire, membranaceous, pale brownish horn-colour ; whorls 5, marked with closely-set, oblique, arcuate, transverse wrinkles ; suture impressed, very narrowly margined below ; umbilicus moderately narrow, deep; columella outwardly expanded above, vitreous, descending in an oblique curve, diffused above into a thin, glassy, ill-defined callus which reaches the upper margin of the labrum ; labrum membranaceous, slightly retlexed, receding below, projecting above; aperture ovate. Alt. 6°25, diam, maj. 14°25, diam. min, 11°75 mm, Aperture : alt. 6°25, diam, 7°25 mm, Hab. Kigezi, extreme 8.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). * For explanation of the Plates see p, 193, 184 MR. H. B. PRESTON ON NEW AFRICARION KEMPI, sp.n. (PI. XXXI. fig. 3.) Shell subovate, with moderately depressed spire, yellowish brown; whorls 3, marked with arcuate, wrinkle-like growth- ridges; suture impressed, narrowly margined below; columella vertically descending above, somewhat obliquely curved below ; labrum simple, projecting in front, receding above and below aperture rather squarely ovate, Alt. 7, diam. ma}. 14, dtam. min. 10°75 mm. Aperture: alt. nearly 7, diam. 8 mm. Hab. Between Entebbe and Mbarara, S.W. Uganda (fobim Kenp). AFRICARION MICROSTRIATA, Sp.n. (PI. XXXT. figs. 4, 4a.) Shell rather small, thin, moderately globose, with small and depressed spire, pale yellowish horn-colour ; whorls 3, the first two very small, the last proportionately very large, marked with transverse, arcuate growth-wrinkles and microscopic, closely-set, wavy, spiral striz; suture impressed; base of shell rather inflated ; columella descending in a strong curve; labrum acute, receding below and sharply above, very prominently projecting in front; aperture very broadly and somewhat compressedly sublunate. Alt. 5°75, diam. ee 11-25, diam. min. 8° mm. Aperture : alt. 5°75, diam. 6: 25 mm. Hab. Between Mbarara and Kigezi, extreme 8.W. Uganda (Robin Kenp). AFRICARION MICROGRANULATA, sp.n. (PI. XXXT. figs. 5, 5a.) Shell differing from 4. microstriata in its much finer sculpture, the spiral strie being very much finer and still more closely set ; inoreover, they are crossed by fine, oblique, transverse striz, thus presenting under the microscope a finely granular appearance. The present species is also rather larger, the last whorl is some- what more inflated, and the labrum less prominently projecting in front; the aperture is much higher in proportion to its breadth, and the columella is even more curved than is the case with A. microstriata. Alt. 8, diam. maj. 12, diam. min. 9 mm. Aperture : alt. 8, diam. 7 mm. Hab. Wigezi, extreme 8.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). VirRINA COMPACTA, sp.n. (Pl. XXXII, fig. 11.) Shell semiorbicular, not very thin, pale brown; whorls 27, rapidiy increasing, smooth but for radiate lines of growth, the last whorl subangulate at the periphery; suture impressed, slightly crenellate and narrowly margined below; base of shell rather inflated; columella descending in a very gentle curve, narrowly outwardly reflexed and diffused into a light callus whieh veaches the upper margin of the labrum; Jabrum simple, the margins converging; aperture broadly subovate. TERRESTRIAL AND FLUVIATILE SHELLS, 185 Alt. 4:5, diam. maj. 9, diam. min, 7 mm. Aperture : alt. 4, diam. 4°75 mm. Hab. Between Mbarara and Kigezi, extreme 5.W. Uganda (Robin Kemp). ZINGIS KEMPI, sp.n. (Pl. XXXII. fig. 14.) Shell small, perforate, thin, rather depressedly turbinate, greenish olive; whorls 33, the earher whorls somewhat pitted, the later sculptured with “oblique, 1 radiate growth-plice, the last whorl subangulate at the periphery ; suture impressed ; base of shell slightly inflated ; umbilicus narrow, deep, slightly overhung by the outward expansion of the columella ; columella somewhat br ‘oudly outwardly expanded, descending in a very slight curve ; labrum acute, simple, receding below; aperture obliquely sublunate. Alt. 2:5, diam. maj. 5°25, diam. min, 4°5 mm. Aperture : alt. 2°25, diam. 2 mm. Hab. Between Mbarara and Kigezi, extreme 8.W. Uganda (Robin Kemp). ZINGIS PAPYRACEA, sp.n. (Pl. XXXIT. fig. 15.). Shell rimate, very thin, globosely turbinate, pale yellowish horn-colour; whorls 5, the first four regularly increasing, the last large, inflated, marked with transverse growth-lines, and minute, wavy, transverse striz ; suture impressed, very narrowly margined below ; perforation very narrow, almost covered by the outward expansion of the columella; columella outwardly reflexed and vertically descending above, curved below; labrum thin, very slightly retlexed, especially towards the base; aperture very broadly and compressedly sublunate. Alt. 8°25, diam. maj. 13°5, diam. min. 11°25 mm, Aperture: alt. 6°75, diam. 6°25 mm. Hab. Kigezi, extreme 8.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). ZINGIS PLANISPIRA, sp.n. (Pl. XXXIUI. fig. 16.) Shell perforate, thin, almost membranaceous, very depressedly tarbinate, semiorbicular, pale yellowish brown, painted with a super-sutural line of dull reddish purple, which appears on the last whorl as a narrow, super-peripheral band; whorls 43, some- what rapidly increasing, the last large and slightly descending in front, sculptured throughout with radiate wrinkles; suture impressed ; umbilicus moderately wide, deep ; columella dese ending in a Sharp curve, outwardly rather bro adly expanded; labrum acute, reflexed throughout ; aperture very broadly and depressedly sublunate. Alt. 6°75, diam. maj. 13°75, diam. min, 11 mm, Aperture; alt. 5, diam. 6 min. HTab, Between Entebbe and Mbarara, Uganda (Pobin Kemp), In shape resembling the Kastern Helicoid genus Planispira, 186 MR. H. B. PRESTON ON NEW THAPSIELLA MILLESTRIATA, sp. n. (Pl. XXXII. fig. 12.) Shell perforate, very depressedly turbinate, thin, pale yellowish brown; whorls 47, regularly and rather rapidly increasing, marked throughout with radiate and very minute and closely-set, wavy, spiral strize; suture impressed, margined below; umbilicus narrow, deep, partly concealed by the outward expansion of the columella ; columella outwardly expanded above, very obliquely descending, a well-defined, outwardly projecting callus reaching from it to the upper margin of the labrum; labrum thin, acute, receding below ; aperture very broadly and compressedly sublunate. Alt. 4, diam. maj. 8, diam. min. 6°75 mm. Aperture: alt. 3°5, diam. nearly 4-25 mm. _ Hab. Near Kigezi, extreme S.W. Uganda, at an altitude of 6000 ft. (obi Kemp). THAPSIELLA OPPOSITA, sp. n. (Pl. XXXII. fig. 13.) Shell differing from Helix zanguebarica Craven * in being spirally sculptured throughout and in having no transverse striz on the spire, whereas 17. zanguebarica has no spirals on the spire but is strongly transversely striate, the basal strize are not so apparent as those on H. zanguebarica; in other respects there is a great resemblance between the two species. Alt. 1°75, diam. maj. 1:5 mm. Hab. Mt. Kenangop, Aberdare Range, British Hast Africa (Robin Kemp). It may be as well to mention here that through the courtesy of Mr. KE. A. Smith I have microscopically examined the type specimen of Mr. Craven’s species in the British Museum, which is, as Stated above, basally spirally striate, though no mention is made of this important character in his description. KALIELLA CONSOBRINA, sp.n. (Pl. XX XI. fig. 11.) Shell rimate, conical, pale brownish horn-colour; whorls 54, sculptured with fine, oblique, slightly wavy, closely-set, transverse strie, the last strongly carinate at the periphery; base of shell rather inflated, marked with lines of growth and fine, wavy, spiral strie ; suture impressed, narrowly but strongly callously margined above; umbilicus reduced to a mere chink; columella outwardly expanded and very vertically descending above, oblique below ; labrum simple; aperture angularly sublunate. Alt. 3°75, diam. maj. nearly 4, diam. min. 3°5 mm. Aperture: alt. 1:25, diam. 1:25 mm. Hab. Between the Igembi Hills and Nyeri, British East Africa (Robin Kemp). KALIELLA DEPAUPERATA, sp.n. (PI. XXXI. figs. 13, 134.) Shell differing from A’. consobrina in its smaller size, it having one whorl less, and in its proportionately broader shape, in being very bluntly carinate at the periphery, and in its rather lighter colour; moreover, it lacks the spiral basal strize of that species. * Proc, Zool. Soc. London, 1880, p. 217, pl. xxii. figs. 4 a, 4, ¢. TERRESTRIAL AND FLUVIATILE SHELLS. 187 5, diam. min. 2°5 mm. Alt. 2, diam. maj. 2°7 Igembi Hills and Nyeri, British East Africa TTab. Between the (Robin Kemp). KALIELLA KIGEZIENSIS, sp.n. (Pl. XXXI. fig. 14.) Shell allied to K. consobrina, but imperforate, narrower in form, with proportionately higher aperture and rather finer transverse sculpture; the columella also descends vertically throughout its whole length. Alt. 3, diam. maj. 3°25, diam. min. 3 mm, Aperture: alt. 1°25, diam, 1 mm. Hab. Between Mbarara and Kigezi, extreme S.W. Uganda ; also at various points in the neighbourhood of Kigezi itself (Robin Kemp). KALIELLA IREDALEI, sp.n. (Pl. XXXI. fig. 12.) Shell rimate, small, conically turbinate, light reddish brown ; whorls 6, rather convex, the last not carinate at the periphery, sculptured with very fine, somewhat oblique, transverse strive ; base of shell marked with lines of growth and sculptured with slightly distant, fine, wavy striez; suture well impressed, not margined ; umbilicus very narrow, partly concealed by the outward expansion of the columella; columella outwardly expanded, vertically descending in a gentle curve above, oblique below ; labrum simple; aperture sublunate. Alt. 2°5, diam. maj. 2°75, diam. min. 2°5 mm. Hab. Between the Igembi Hills and Nyeri, British Kast Africa (Robin Kemp). The very characteristic sculpture of this pretty little species is only visible under the microscope. SITALA IREDALEI, sp. n. (Pl. XXXI. fig. 15.) Shell rather acuminately turbinate, with convex base, pale greyish yellow ; whorls 6, somewhat rapidly increasing, the last inflated, sculptured with microscopic, spiral striz and oblique, transverse riblets or creases; suture impressed; columella vertically descending, slightly angled below ; aperture ovate. Alt. 4°25, diam. maj. 4°25 mm. Aperture: alt. 2, diam. 1°75 mm. Hab. Mt. Kenangop, Aberdare Range, British East Africa (Robin Kemp). TTRACHYCYSTIS IREDALEI, sp.n. (Pl. XXXII. figs. 8, 8a, 80.) Shell small, depressedly suborbicular, almost planulate, reddish brown; whorls 3, the apical whorl large, smooth, the remainder sculptured throughout with rather fine and closely-set, obliquely arcuate, transverse costule, between which ocevr very fine, transverse striz, crossed by extremely fine spirals, both these last and the transverse strie being only visible with the aid of the microscope; suture well impressed ; umbilicus very wide and 188 MR, H. B. PRESTON ON NEW rather deep; columella very oblique; labrum simple; aperture broadly sublunate. Alt. °75, diam. maj. 2, diam. min. 1:75 mm. Hab. Between the lgembi Hills and Nyeri, British Kast Africa (ftobin Kemp). LEUCOCHILOIDES CHANLERENSIS, sp.n. (Pl. XX XI. fig. 16.) Shell small, rimate, cylindrically fusiform, slghtly shining, reddish brown ; whorls 5, regularly increasing, the last ascending in front, marked with oblique, transverse growth-lines; suture well impressed ; umbilicus very narrow; columella curved ; labrum rather narrowly expanded, whitish, not reflexed; aperture sub- circular, bearing a single, nodulous denticle just below the point of insertion of the labrum with the parietal wall. Alt. nearly 4, diam. maj. 1°75 mm. Aperture: alt. °75, diam. nearly -75 mm. Hab. Chanler Falls, Eusso Nyiro, British Kast Africa (Rodin Kemp). LEUCOCHILOIDES IREDALET, sp.n. (PI. XXXII. fig. 18.) Shell differing from ZL. chanlerensis in its blunter form, more swollen whorls, deeper suture, more open umbilicus, straighter columella, and narrower and more erect labrum ; moreover, it lacks the nodulous denticle which in the present species is replaced by an erect white denticle situate low down on the parietal wall well within the aperture, and a smaller erect squarish denticle on the columella also situate well within the opening. Alt. 3°5, diam. maj. 1°75 mm. Aperture: alt. °75, diam. nearly ‘75 mm. Hab. Kusso Nyiro, British East Africa (Robin Hemp). LErUCOCHILOIDES soroR, sp.n. (PI. XX XI. fig. 17.) Very closely allied to Z. chanlerensis and possibly only a variety of that species; it differs, however, in its larger size, more open umbilicus, though having a proportionately narrower base, and in having an additional whorl, the aperture is also more ovate than is the case in that species. Alt. 6, diam. maj. 2°25 mm. Aperture: alt. 1:5, diam. 1°25 mm. Hab. Chanler Falls, Eusso Nyiro, British East Africa (2obin Kemp). LEUCOCHILOIDES GAZIENSIS, sp.n. (Pl. XX XI. fig. 19.) Shell small, ovately fusiform, pale reddish brown; whorls 5, convex, marked with fine, oblique, transverse striz ; suture deeply impressed; umbilical area broadly depressed: labrum with converging upper margin, white, rather broadly expanded ; aperture ovate. Alt. nearly 4°5, diam. maj. 2°25, diam. min. 2 mm. Aperture: alt. 1, diam. -5 mm. fab. Gaa, British East Africa (Robin Kemp). TERRESTRIAL AND FLUVIATILE SHELLS, 189 ALA KENIANA, sp.n. (PI. XXXI. fig. 6.) Shell minute, cylindrically ovate with very obtuse apex, scarcely rimate, moderately thin, pale reddish chestnut ; whorls 4, convex, shouldered above, marked with fine, oblique, transverse striz and slightly malleated; suture well impressed; columella whitish, internally broad; labrum erectly reflexed, the margins joined by a thin a callus ; aperture very broadly inversely auriform. Alt. 2, diam. maj. 2°25 mm. Hab. Mt. Kenia, at an altitude of from 6000 to 9000 ft. (Robin Kemp). Homorvs IREDALEI, sp. n. (Pl. XX XI. fig. 10.) Shell moderately large, subulately fusiform, with minute apex, covered with a yellowish periostracum, on the lower whorls closely, obliquely, transversely banded with dark blackish purple; whorls 10, flattened, the first minute, the second proportionately large, the pom ainder regularly increasing, smooth but for lines “of growth ; suture lightly impressed, faintly crenellate below ; columella short, gently curved, abruptly truncate, diffused above into a thickish, well-defined callus which reaahies the upper margin of the labrum ; ; labrum simple; aperture elongately ovate. Alt: 31°25, diam, maj. 9:25 mm. Aperture: alt. 8°5, diam. 4°5 mm. Hab. Between Mbarara and Kigezi, extreme 8.W. Uganda (Robin Kemp). SuccinEA KEMPI, sp.n. (Pl. XXXII. figs. 2, 2a.) Shell ovate, opaque, cream-coloured ; remaining whorls 2, the first very small, the last comparatively very large, marked only with lines of growth ; suture impressed, broadly margined below ; columella very obliquely curved ; labrum simple, acute ; aperture dilated, ovate. Alt. 7°25, diam. maj. 5:5, diam. min. 3:25 mm. Aperture: alt. 6, diam. 4 mm. Hab. Between Entebbe and Mbarara, 8.W. Uganda (Robin Kemp). A remarkable form, easily recognizable by its minute spire and enormously large last whorl. SUCCINEA PRINCEI, sp.n. (Pl. XXXII. figs. 3, 3.) Shell ovately fusiform, very thin, pale yellowish horn-colour; whorls 22, the last very long, polished, smooth but for lines of growth ; columella arched ; aper ture dilated, very lar ge. Alt. 7°25, diam. ee 3°D mm. Aperture: alt. 5, diam. 2°5 mm. Hab. Nakuru, British East Africa (Robin Kemp), BLAUNERIA EXSILIUM, sp. n. (Pl. XXXI. fig. 8.) Shell subulate, thin, pale yellowish horn-colour; whorls 8, smooth but for lines of growth, polished, shining, flat; suture 190 Mi. H. B. PRESTON ON NEW linear, broadly margined below; columelia arched, white, extending into a thick, white, narrow, well-defined callus, bearing a single plait above, obliquely truncate below; labrum acute, whitish ; aperture narrowly inversely auriform. Alt. 4°5, diam. maj. 1:25 mm. Aperture: alt. 1-5, diam. -5 mm. Hab. Gazi, British Hast Africa (Robin Kemp). ANCYLUS KEMPI, sp. n. (PI. XXXI. figs. 2, 2 a.) Shell rectangularly ovate, depressed, somewhat sinuous on the left side, with subcentral apex, olive-brown, marked with concentric growth-lines, and indistinctly sculptured towards the margin with faint, radiate striz, which are more visible on the interior surface of the shell; margin acute; interior of shell polished, shining, ale brown. Alt. 1:25, diam. maj. 4°25, diam. min. 3°25 mm. Hab. Kigezi, extreme 8.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). LIMN#A KEMPI, sp.n. (Pl. XXXII. fig. 1.) Shell small, ovately fusiform, thin, pale reddish brown ; whorls 3, the last large and somewhat elongate, marked with fine, silky, transverse growth-strie; suture well impressed; columella obliquely descending, not twisted or arched above, diffused into a very thin, well-defined, parietal callus which reaches the upper margin of the labrum; Jabrum simple, acute, somewhat dilated at the base; aperture very elongately ovate. Alt. 7-5, diam. maj. 4 mm. Aperture: alt. 5, diam. 2°5 min. Hab. Kisumi, Lake Victoria Nyanza, British East Africa (Robin Kemp). PLANORBIS KIGEZIENSIS, sp.n. (Pl. XXXII. figs. 5, 5a, 5 6.) Shell small, depressed, suborbicular, with concave spire, thin, pale greenish grey; whorls 4, regularly and rather rapidly increasing, the last obtusely angled above, somewhat sharply angled below, sculptured with fine, closely-set, arcuate, transverse striz; suture well impressed; base of shell not very convex ; umbilical depression very wide, shallow; columella descending very obliquely and diffused above into a projecting callus which reaches the upper margin of the labrum ; labrum simple, acute, projecting in front, receding above and below, the margins converging ; aperture subelliptical. Alt. 1, diam. maj. nearly 3°5, diam. min. 3 mm. Hab. Kigezi, extreme S.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). PLANORBIS SPERABILIS, sp. n. (Pl XXXII. figs. 4, 4a, 4 0.) Shell very small, depressedly orbicular, thin, greyish-yellow horn-colour; whorls 3, rather rapidly increasing, marked with TERRESTRIAL AND FLUVIATILE SHELLS. 191 somewhat strong, radiate growth-lines; base of shell slightly concave ; labrum receding below, the mar gins joined by a thin callus ; aperture subcircular. Alt. nearly ‘5, Sa maj. nearly 2, diam. min, 1°) mm. Aperture : alt. 25, diam. ‘25 mm. Hab. Gazi, British’ East Africa (Robin Kemp). SEGMENTINA EUSSOENSIS, sp.n. (Pl. XXXII. figs. 6, 6a, 66.) Shell depressedly orbicular, with concave spire and almost planulate base, pale yellowish wax-colour, polished, somewhat shining; whorls 43, rapidly i increasing, the last large and rounded, angled above and bluntly carinate at the per iphery, below which ae base of the shell is nearly flat; suture rather lightly impressed, margined below; umbilicus wide, shallow; labrum thin, 1 rapidly receding below ; aperture depressedly and angularly sublunate. Alt. 1°5, diam. Ea 5°25, diam. min. 4°75 mm. Aperture: alt. 1°25, Santi: 1 mm. Hab. Chanler Falls, Eusso Nyiro, British East Africa (Robin Kemp). SEGMENTINA KEMPI, sp.n. (Pl. XXXII. figs. 7, 7a, 7b.) Shell small, suborbicular, planulate above and below, with concave spire, Avhite: polished, shining; whorls 4, the first three small, regularly increasing, the last very large, founded above, sharply angular below, indistinctly sculptured with microscopic, silky, transverse strie ; suture impressed, irregular; umbilicus moderately narrow, and deep; columella obliquely descending, angled below, extending above into a parietal callus which joins the upper or sutural margin of the last whorl well within the shell; labrum acute, receding below ; aperture triangular. Alt. 1, diam. maj. 3°75, diam. min. 2°25 mm. Hab. Kigezi, extreme S.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). VIVIPARA RUBICUNDA, v. Martens, var. KISUMIENSIS, var. n. (Pl. XXXIT. fig. 9.) Shell differing from the typical form in its larger size, darker colour, and in ‘being proportionately higher and narrower, the apertur e is also more ovate and the peristome edged with black. Alt. 28, diam. maj. 15°75, diam. min. 12 mm. Aperture: alt. 10, diam. 7 mm. Hab. Kisumi, Lake Victoria Nyanza, British East Africa (Robin Kemp). ASSIMANIA AURIFERA, sp.n. (Pl. XXXI. fig. 9.) Shell turbinate, perforate, thin, semitransparent, dark brownish horn-colour, minutely and densely freckled with golden yellow; whorls 53, regularly increasing, shouldered above, convex, very minutely spirally striate; suture well impressed ; umbilicus moderately wide, deep; columella very oblique, obtuse-angled, 192 MR. H. B. PRESTON ON NEW slightly outwardly reflexed; labrum simple, acute; aperture irregularly roundly ovate. Alt. 3:75, diam. maj. 2°75 mm. Aperture: alt. 1-5, diam. 1 mm. Hab. Gazi, British East Africa (Robin Kemp). Evssora, gen. n. Shell solid, conical, resembling Assemania, but without oper- eulum, though fluviatile in its habits. Type of genus, 4. inopina. The genus, as above stated, bears a great resemblance to Assi- mania, but though I have been able to examine a jarge number of specimens collected alive, and which still contained the decaying animal, J have been unable to find any trace of operculum : more- over, on physiographical grounds alone, I should be loth to refer it to that genus, which is essentially a coast form, whereas the po at which the present specimens were collected is at least 375 miles from the nearest point on the African sea-board, and it is extremely probable, judging by the maps at my disposal, that the connection by water between the locality where the present species was collected and the sea is very much more than that distance ; the Eusso Nyiroafter flowing through Lake Lorian, is at present believed to flow out of that lake as the Wakes River, a tributary of the Juba, which it joins not far from its mouth and which forms the north-eastern boundary-line between British East Africa and Italian Somaliland. Pending the examination of the animal, which in the specimens sent home by Mr. Kemp was not in sufficiently good condition for dissectional purposes, I propose to place the genus temporarily in the vicinity of the Assimanieide. KUSsOIA INOPINA, sp. n. (PI. XXXIT. fig. 10.) Shell small, rimate, turbinately conic, dark reddish brown ; whorls 54, regularly increasing, flattish, except the last, which is somewhat globose, marked only with transverse growth-lines ; suture impressed ; umbilicus very narrow, almost covered by the dilation of the columella; columella descending in a rounded curve, rather erectly dilated, diffused above into a thin, parietal callus; labrum simple; aperture subovate. Alt. 3°5, diam. maj. 2°5, diam. min. 2 mm. Aperture: alt. 1°75, diam. 1°25 mm. Hab. Banks of the Eusso Nyiro River, Br “us East Africa (Robin Kemp). SPHARIUM KIGEZIENSIS, sp. n. (Pl. XX XI. figs. 1, 1 a.) Shell very small, triangularly ovate, yellowish red ; both valves closely concentrically striate, the striz being rather coarser towards the umbonal region; umbones rather large, not prominent ; dorsal margin sharply arched ; ventral margin gently rounded ; anterior side rather abruptly descending ; “posterior side sub- rostrate, somewhat angularly rounded ; cardinal tooth in right TERRESTRIAL AND FLUVIATILE SHELLS. 193 valve small, oblique, slightly notched anteriorly ; cardinal teeth in left valve very small, converging; lateral teeth in right valve very weak, in left valve weak, somewhat curved; scars very lightly impressed ; interior of shell somewhat granular. Long. 3, lat. 3°5 mm. Hab. Kigezi, extreme S.W. Uganda, at an altitude of 6000 ft. (Robin Kemp). EXPLANATION OF THE PLATES. Proate XXXI. Fig. 1. Spherium kigeziensis, X 5. Was > is hinge, X 5. 2&2a. Ancylus kempi, X 5. _ 3. Africarion kempi, nat. size. 4, x microstriata, X 14. 4a. 4 5 sculpture, X 12. 5 a6 microgranulata, X 1. 5a. a S sculpture, X 12. 6. Alea keniana, X 10. 7. Ennea microstriata, X 2%. 8. Blauneria exsilium, X 5. 9. Assimania aurifera, X 6. 10. Homorus iredalei, nat. size. 11. Kaliella consobrina, X 6. 12. ‘A iredalei, * 6. 13. a depauperata, X 6. Hsia, 55 i sculpture, X 12. 14. 5a higeziensis, X 6. 15. Sitala iredalei, X 4. 16. Leucochiloides chanlerensis, X 7. 17. os soror, X 4. 18. a iredalei, X 7. ; 53 gaziensis, X 6. 20. Natalina permembranacea, X 1s. PAO aR Er spire, X 1}. 20Ibe" ss % base, X 15. PLatE XXXII. Fig. 1. Limnea kempi, X 3. 2 &2a. Suecinea kempi, X 25. 3&3a. 5 princei, X 25. 4, Planorbis sperabilis, X 8. La. a 3 spire, X 8. Ab. a - base, X 8 5. 4 kigeziensis, X 6. Site 5 . spire, X 6 55. = base, X 6. 6. Segmentina eussoensis, X 3. 6a. 5 H spire, X 3. 6 b. Pe a base, X 3. if i kempi, X 6. 7 ” ” spire, x 6. “Aloe fs »» base, X 6. 8. Trachycystis iredalei, X 8. 8 x = spire, X 8. 8 + os base, X 8. 9. Vivipara rubicunda, var. kisumiensis, nat. size. 10. Hussoia inopina, X 5. 11. Vitrina compacta, X 2. 12. Thapsiella millestriata, X 2. 13. ES opposita, X 8. 14. Zingis kempi, X 4. 15. 4, papyracea, X 13. 16. » planispira, X 13. Proc. Zoot. Soc.—1912, No. XIII. 13 194 MR. F. E. BEDDARD ON A 13. Contributions to the Anatomy and Systematic Arrange- ment of the Cestoidea. By Frank EH. Bepparp, M.A., F.R.S., F.Z.8., Prosector to the Society. [Received November 1, 1911: Read November 21, 1911.] (Text-figures 19-30.) II]. On a New Genus or Tarpeworms (Ofiditenia) FROM THE BustarD (Lupodotis kort). An example of the South-African Bustard (Hupodotis kort) on April 27th, 1911, voided a number of white curiously-shaped bodies, the nature of which I did not recognise until they were submitted to microscopic examination. The shape of these bodies may be learnt by an inspection of text-figure 19. They are separate mature proglottids of a tapeworm, of which I obtained complete specimens later (on May 7th), when the bird died. Since the Bustard was acquired by the Society on October Ist, 1910, 16 seems likely that the infection did not take place in the Society’s Gardens, but that the parasites were already present when the bird arrived. Text-fig. 19. Ripe and detached proglottids of Otiditenia ewpodotidis. A most useful and presumably comprehensive list of the tape- worms of birds has been quite recently published by Prof. Fuhr- mann*. From this it would appear that only the following species have been found in the Otidiformes, and that none at all have been met with in Hupodotis kori—if it has been examined from this * “Die Cestoden der Vogel,” Zool. Jahrb. 1908, Suppl.-Bd. x. NEW AVIAN TAPEWORM. 195 point of view. The species are /diogenes otidis, Chapmannia lapica, Hymenolepis villosa, H. tetracis, and H. ambiguus. There is no doubt that the species which forms the subject of the present communication to the Society is none of these; nor can I reconcile its characters with those of any other genus of 'Tapeworms of the group Tetracotylea (of which group it is undoubtedly a member) which have been described up to the present. I shall, however, defer the attempt to fix its systematic position until I have described its anatomical characters. I have examined feur complete specimens of this worm, besides some fragments which may or may not have belonged to those specimens. The largest was about 3 inches in length, and the greatest diameter of the posterior segments was 4 mm. ‘The diameter of the body gradually increases from the head up to the point of greatest diameter, and then remains the same ; there is not, as in so many tapeworms, a narrow anterior region of the body, which suddenly widens within the limits of two or three proglottids. The general shape is thus much like that of certain species of Bertiella, for example of B. cercopithect*. There is, however, no further resemblance between the present genus and Bertiella in external form. The worm is white in colour; but there is some black pigment in the head behind the suckers, and the ripe proglottids are of a brick-red hue. The scolex of this new worm—for which I propose the generic and specific names of Otiditenia eupodotidis, as indicative of its habitat—is not particularly small nor, on the other hand, con- spicuous by its large size. I have not found the least trace of hooks anywhere on the suckers. The head seems be completely unarmed as to the suckers, but the rostellum has hooks. The four suckers are, as is so often the case, extremely mobile, and can be protruded a long way from the head as cylindrical processes. In this case they look rather forwards than outwards. When retracted and in a normal condition the suckers look out- wards and slightly upwards. When fully protruded the suckers give to the head of this worm an appearance very like that of the genus of Tetraphyllidea, Cylindrophorus *. I have investigated the structure of the rostellum and lateral suckers by transverse sections through the head. There is nothing remarkable about the structure of the suckers. The rostellum, however, demands some consideration. When the worm is ex- amined with a lens or with a low power only of the microscope, the appearance presented is that of a median sucker such as occurs sometimes, though, as it is stated by Kiichenmeister ¢, not always, in Tenia saginata. The hooks are, in fact, so minute that I was unable to detect them when studying the worm in that fashion. Nor can they be detected save with high-powered lenses. The varying condition of the retraction of the median sucker, or rather * See Beddard, P. Z.S. 1911, p. 640, text-fig. 151. + Bronn’s ‘ Klassen u. Ordnungen des Thierreichs,’ Bd. iv. Taf. 42. fig. 14, { ‘Die Parasiten des Menschen,’ Leipsic 1881, p. 140, pl. ii. fig. 3. 13* 196 MR. F. E. BEDDARD ON A rostellum, renders it apparently absent or more feebly developed in some individuals than in others. And there is here a resem- blance to the otherwise not closely allied Tenia saginata. This median sucker is, indeed, a not much more developed structure than the rudimentary rostellum of Z’enia saginata. In this latter species Railliet* speaks of “‘le rostre faisant défaut et se trouvant remplacé fréquemment par une légere dépression ” ; while Leuckart 1, in defining the species, states that “‘the head has a flattened crown with a pit-like hollow in the middle.” On the other hand, Kiichenmeister, while emphasizing the occasional absence of any such depression in both text and figure, also figures { an organ very like a sucker, and certainly more than a mere depression. ‘The structure, however, is not, according to Leuckart §, a sucker, but a rudimentary rostellum with a distinct lenticular muscular mass. Leuckart’s figure of a section through this ““sucker” is copied in Bronn’s ‘'Thierreichs’ (Bd. iv. p. 1203). The accompanying text-figure (text-fig. 20) shows a median longitudinal section through the scolex of Onditenia, illustrating the: rudimentary rostellum and enabling it to be compared with the adjacent suckers. The simplicity ‘of the really sucker-like rostellum will be apparent from this figure, which represents the rostellum in a contracted state withdrawn into the scolex. Inasmuch as the sete border the rostellum in a double circle, they are not visible in such a preparation, only one or two being seen in each section at the two corners of the rostellum. The rostellum itself is obviously (to my mind) no more, or very little more, developed than that of Tcenia saginata, already referred to; its muscular layer is not thicker than that of the suckers, as will be seen from my figure. This obviously contrasts greatly with complicated and more typical rostella ||. It will be observed, moreover, that the floor of the cavity into which the rostellum is retractile—which floor constitutes the rostellum—is hardly, if at all, thicker than the lateral walls of the cavity; that the whole structure, in fact, does not greatly differ froma sucker. It may be borne in mind that this is a possible origin of the rostellum, though the theory that it is the meta- morphosed remains of a pharynx has been put forward. On the other hand, the nuclei are more densely packed in the rostellum than in the suckers, as the figure referred to shows. This difference is, however, perhaps partly due to the more contracted condition of the rostellum, and possibly also to its greater con- tractility. Again, the layer of chitin covering the rostellum is very much thicker than that which lines the suckers—the latter being, indeed, inappreciable. ‘There is some black pigment in the head behind the suckers. My preparations unfortunately do not allow me to give any * “Tyraité de Zoologie Médicale et Agricole,’ ed. 2, Paris 1895, p. 232. + ‘The Parasites of Man’ (Engl. ed. transl. by Hoyle), Edinburgh 1886, p. 407. {t Loe. cit. pl. vi. fig. 8. is Loe. cit. p. 435. || Cf, e.g.) Bronn’s ‘ Thierreichs,’ Bd. iv. figs. 56, 57, 58, pp. 1826-1328. NEW AVIAN TAPEWORM., 197 accurate account or figures of the rostellar hooks. I can only say that they are curved and hook-like, not straight, and very numerous, certainly at least 150 in number, and probably more, and that they are disposed in an alternating fashion, forming a double crown. Text-fig. 20, a : oa ae Bea Pad Longitudinal section through scolex of Otiditenia ewpodotidis. R. Rudimentary rostellum (the hooks are too small to appear). S. One or the suckers. NV. Lateral nerve-cord of one side. The longitudinal section from which the annexed text-figure of the rostellum was drawn also shows very well the existence of a neck in this tapeworm. It varies much in length, though it is never longer than the length of three or four proglottids immediately following upon it. On the other hand, it is some- times very short, not more than the length of the first proglottid. If this had not been observed in the living worm, where the neck is much more distinct, as such, from the proglottids than in aleohol- 198 MR. F. E. BEDDARD ON A preserved material, it might easily be supposed that this species was characterised by the absence of a neck. Such a mistake may have been made with other species. Text-fig. 21. Two examples of Otiditenia eupodotidis differing slightly in progressive increase of size of proglottids. The general character of the segmentation and the form of the individual proglottids is shown in text-figure 21, which represents two individuals which are slightly different in these characters. In one of them the segments increase in length more rapidly than in the other; but in neither are the posterior segments longer than they are broad. Nor do they even get to be so long, except in the case of the detached proglottids. As the segments advance towards maturity the projection of one segment over that which follows is seen to be more marked, and it forms quite a sharp-edged frill, as is shown in the drawings referred to, The completely NEW AVIAN TAPEWORM. 199 mature proglottids are represented in several aspects in text- figure 19 (p. 194). These proglottids, as there depicted, have a very peculiar form, and have quite lost the flattened appearance of the anterior region of the strobila. They are, indeed, almost spherical in general outline. The projecting frill remains, but its edges are closely adpressed. A single proglottid presents much the appearance of a full sack with the lips of the mouth closely drawn together. Left-hand figure a ventral view of eight nearly mature proglottids of Otiditenia eupodotidis. Right-hand figure a lateral view of the same showing genital pores. The last external character to be noticed is the position and character of the genital pores. These are irregularly alternate. The pores are simple orifices upon the lateral surfaces of the proglottids, and are not in any way prolonged into a spout-like outgrowth. They are, however, situated on an area which covers the whole of the lateral face of the segment, and is slightly raised ; it is also whiter in colour than the rest of the (rather yellowish) body. Finally, the segment is longer from before backwards on the side which bears the genital pore; this inequality of the two sides of a segment enables the position of a genital pore to be fixed without actually inspecting the orifice (text-fig. 22). In transverse sections of the body before the reproductive organs ave to be seen, except in rudiment, the cortical parenchyma will be observed to be fully as thick as the medullary parenchyma. Indeed, anteriorly in the segment before the overlapping frill has detached itself the cortical parenchyma is actually the thicker. The longitudinal muscle-fibres seen in this layer are disposed 200 MR. F. E. BEDDARD ON A singly in the more peripheral regions; more centrally they are ageregated into bundles, the number of fibres being larger in the deeper strata. In the largest I have counted 14 or 15 fibres. Within this layer and bounding the medullary parenchyma is a iayer of delicate circular fibres. In older proglottids the number of longitudinal fibres to a bundle may be considerably greater and the strength of the circular layer has increased. This latter fact is particularly to be noted in the segments which are nearly ready for detachment. The water vascular tubes are the usual four longitudinal trunks, of which—as is again usual—the dorsal is smaller and has much thicker walls. The larger ventral tubes are connected by a rather wide commissural vessel in each segment. The dorsal vessels are apt to vary a little in their relation to the ventral vessels; but they are never superposed, ?. e. directly dorsal and ventral to each other, The dorsal vessel, in fact, lies to the inside of the ventral Text-fig. 23. Transverse section through an immature proglottid of Otiditenia eupodotidis. The larger ventral water vascular tubes lie below and rather to the outside of the smaller dorsal vessels. vessel, sometimes absolutely parallel with it and sometimes more dorsally inclined. The capacity of the large ventral vessel tends to vary; I have seen it to be almost obliterated for a short space. In the anterior segments of the body there is much less difference in calibre between the water vascular vessels than is to be seen later. The testes of this tapeworm lie quite posteriorly in the segment, and thus behind all the other parts of the generative system. In sagittal sections of young proglottids in which the testes are mature or nearly so, but in which the uterus is not yet much NEW AVIAN TAPEWORM. 201 developed, a straight line joining the posterior angles formed by the outgrowths of the segments dorsally and ventrally is just in contact with the posterior boundary of the mass of testes. Anteriorly they are well separated from, though very close to, the ovaries. ‘The testes, in fact, in the genus described in the present paper do not straggle over the segment as they are represented to Text-fig. 24. Upper figure a horizontal section through four not completely ripe proglottids of Otiditenia ewpodotidis. Ov. Ovary. T. Mass of testes. U. Uterus. Lower figure a portion of a transverse section through a proglottid, showing the division of the layer of circular muscles (C.m.) to enclose the young uterus. 202 MR, F. E. BEDDARD ON A do in the allied genus Choanotenia—for example, in the species Ch. galbula and Ch. infundibulum figured by Cohn * Text-fig. 25. Horizontal section through three not fully mature proglottids of Otiditenia eupodotidis. d. Dorsal water vascular tube. W. Ventral ditto. 7. Mass of testes. U. Uterus. * “Jur Anatomie etc. der Vogelcestoden,’ Nova Acta Ac. Nat. Curios. Ixxix. Be pl. 31. fig. 40 & pl. 32. fig. 47. NEW AVIAN TAPEWORM. 203 The testes of Otiditania (text-fig. 24, p. 201) form, in fact, a very compact mass, which almost suggests a single organ whose com- pactness and general characters form a very distinguishing mark of this genus. In the sagittal sections already referred to, the mass of testes is seen to form a band rather lenticular in outline, 2. é. tapering dorsally and ventrally, which extends without inter- mission from the dorsal to the ventral muscular body-wall. In transverse sections of the worm the testicular mass is seen equally well to form an unbroken dorso-ventral layer occupying the whole of the central parenchyma between the larger ventral water vascular vessels, to the outside of which the testes do not extend. The wall of testes which thus exists—-marking, as has already been said, the posterior region of the proglottid—is a very thin one. It is formed of only a single layer or in parts of two layers of testes. In their general form the testes are oval. The very small amount of space occupied by the testes in an antero-posterior plane is striking ; but it is greater in the less fully than in the more fully mature proglottids. In the former the antero-posterior diameter of the group of testes is a little more than one-third of the length of the segment; in the latter perhaps one-tenth, and the disproportion becomes even greater in absolutely ripe seg- ments, where, indeed, the testes finally disappear, being apparently pressed out of existence by the swelling proglottids. In such tapeworms as I am acquainted with by first-hand knowledge the testes are scattered in the medullary parenchyma, though often closely adpressed ; but there is no particular modi- fication of the medullary parenchyma in the region occupied by the testes. The same conditions appear to obtain in many forms described by others. In Otiditenia, however, the testes lie in a very distinct cavity, which has in sagittal sections of the entire proglottid a lenticular outline already mentioned. This cavity is not everywhere apparent as actual spaces lying outside of the testes ; it is for the most part filled up with an interstitial tissue, which separates the individual testes and in which they lie closely packed together. Although this interstitial tissue is not very different in appearance from the medullary parenchyma, it is separated from it by a distinct boundary-line and is more faintly stained by carmine, and does not seem to contain any calcareous corpuscles. The distinctness of the mass of testes, as a whole, from the surrounding regions of the proglottid will be apparent from text-figure 26 (p. 204). Here and there the interstitial tissue seems to be replaced by actual cavities which contain no fluid that takes a stain. They appear, in fact, to be empty. Since the testes le quite posteriorly in the segments, it is obvious that they must be close to the transverse vessels of the water vascular system, which unite the ventral vessels. ‘The spaces to which I have referred, I believe, entirely belong to the transverse water vascular trunks which are large in the 204 MR. F. E. BEDDARD ON A present species. Though the individual testes appear at first sight to be actually bathed by the fluid of the excretory tube, a more careful examination has always shown a layer of interstitial tissue separating the actual testes from the water vascular spaces. The testes, however, do project with their covering into the spaces (see text-fig. 25, p. 202) here and there, and there is thus a very close anatomical relation between them. Text-fig. 26. sit Sagittal section through three proglottids of Otiditenia eupodotidis. T. Mass of testes. U. Uterus. In longitudinal horizontal sections (text-fig. 25) it is obvious that the testes of Otiditenia form a layer which is, as a rule, only one thick, though here and there two testes lie one in front of the other. The distinction between the interstitial tissue separating NEW AVIAN TAPEWORM. 205 the individual testes and the general medullary parenchyma. is strikingly obvious in such sections, inasmuch as the whole area can be seen in a single section extending from one side of the body to the other. Such sections also show particularly well the fact that the testes extend rather beyond the large ventral water vascular vessel on the fore side, where, indeed, they occasionally nearly touch the outer skin. The extension is not quite so great on the opposite side, though the mass of testes usually bulges into the vessel, and, as already mentioned, presents very much the appearance of lying in it. It is to be noticed also that in these lateral extensions of the testes the whole mass gets very much wider from back to front, the testes being three or four deep. These outgrowths intrench upon the area occupied by the coils of the vas deferens, and push laterally and flatten out that coil. The extension of this testicular mass laterally is highly suggestive of its being a single organ growing as a whole and not merely an association of separate and quite individualized testes. The inter- stitial substance which divides the testes presents the appearance in the direction of its fibrils of having flowed laterally, carrying with it the enclosed testes. Multiplying the 30 or so testes which are visible in a horizontal section by the 6 or 7 which are visible in a sagittal section, we get a total of 200 or so, which may be slightly increased to include the testes found in the lateral extensions of the testicular area just referred to. The ovaries are very obvious in the segments where they occur ; but they disappear early in the strobila and are represented thenceforward by mere vestiges. The ovaries are to the fore side of the segment and closer to that margin of the strobila than the vitelline gland, to which, however, they are closely contiguous. They commence on the level of the receptaculum and lie on both dorsal and ventral sides of that portion of the ovidueal tube, hence getting a double character—the ventral half (or more ventral ovary, if we speak of two) is considerably the larger. They lie posteriorly in the segment, but between the testes and the uterus. They by no means occupy the whole breadth of the medullary parenchyma in a sagittal section, as do the testes when fully developed. The cloaca genitalis opens on to the exterior directly. There is no papilla-like process bearing a genital orifice. As already mentioned, the pores are irregularly alternate in position, and I have seen as many as six consecutive pores on the same side of the body. The cavity of this conjoined region of the genital ducts is rather wide and of some length; the lumen is slit-like to circular, but the walls never seem to be crumpled so as to give a star-like appearance to the lumen. The cavity is lined by a very thick layer of cuticle which stains very deeply in carmine. The walls of the cloaca genitalis contain at some little distance from the chitinous lining a sheath of loosely packed large muscle-fibres, which completely encircle the tube and run in a longitudinal direction. The fibres form several layers when seen in transverse 206 MR. F. E. BEDDARD ON A section, and are very conspicuous on account of their deep stain- ing with carmine. The cloaca genitalis is very nearly as deep as Text-fig. 27. Cirrus sac of Otiditenia eupodotidis. C. Extensions of genital cloaca. C.S. Expanded region of cirrus sac. x2. Narrow region of sperm-duct. « in genital cloaca points to spines on “ penis.” NEW AVIAN TAPEWORM. 207 the length of the cirrus sac. When the entire system of genital ducts is seen in longitudinal section, 7. e. in transverse sections of the proglottid, it will be observed that the cirrus sac projects into the cloaca genitalis, and that the latter is therefore prolonged backwards as a kind of collar surrounding the protrusible part of the cirrus sac. Dr. Gough has figured in Stilesia hepatica* a similar backward growth of the cavity of the cloaca genitalis. In such longitudinal sections of the cloaca genitalis of Otiditenia it will be observed that the cavity is not so regular as I have seen it in transverse sections ; there are lateral foldings of the lumen which are probably paired and thus produce no appearance of crumpling when the organ is viewed in transverse sections. The vagina and cirrus sac, of course, open into this cloaca, the vagina nearer to the external orifice of the cloaca genitalis. In following out a series of sagittal sections of the proglottids, which are, of course, transverse to the direction of the cloaca genitalis, it will be seen that, as a rule, the cirrus sac becomes separate from the vagina in a position which is at first obliquely anterior to the vagina. This is the same on both sides of the body ; but it is not invariably that the cirrus sae thus opens into the genital cloaca anteriorly of the vagina. I have seen one case (text- fig. 28, p. 208) in which the vagina lay anteriorly to the cirrus sac, and in this case an obliquity occurred in the relative positions of the two tubes, but the obliquity was in the reverse direction to that shown in the normal arrangement. The obliquity, that is the more dorsal or ventral inclination of the cirrus sac to the vagina, 1s already known to vary; thus, in Monieza the position in relation to each other of the two tubes varies according as to whether they belong to the right or left side of the body, while in Avitellina centripunctata Dr. Gough has figured, in his paper already referred tot, an alternation of this kind in successive segments and on the same side of the body. There is, however, here no question of a reversal of an anterior to a posterior position such as I have found in Otiditenia eupodotidis. In one case I found another remarkable variation. This was the complete absence of the proximal part of the vagina; into the cloaca genitalis opened only a cirrus sac. However, as the series of sections in which I cbserved this variation was traced further towards the middle line of the body, the median region of the vagina, which is of small calibre, came into view. In any case, the wide region of that tube which, in normal cases, opens into the cloaca genitalis was completely absent, save, indeed, for a few traces of its muscular longitudinal sheath. The vagina issues from the cloaca genitalis in an oblique position, as seen when the worm is studied in a series of sagittal sections, save, of course, for the exceptions mentioned above. — It runs parallel with and later in close contact with the dense coil of * “A Monograph of the Tapeworms of the Subfamily Avitellininz,” Quart. Journ. Mier. Sci. vol. lvi. 1911, pl. xii. fig. 16, at. + Loc. cit. pl. xiv. fig. 43. 208 MR. F. E. BEDDARD ON A the vas deferens on the ventral side. At first the vagina is wide, with a much plicated lining epithelium surrounded by a thick layer of muscles. It then suddenly becomes much narrower— these two regions of the vagina being thus analogous to the wider distal sac-like part of the cirrus and the narrow proximal part of the same. The narrow region of the vagina joins the wider region at an angle. Followed back the narrow part of the vagina dilates with moderate abruptness into the large receptaculum seminis, which commences at a point about on a level with the pore side of the large ventral water vascular vessel. Text-fig. 28. Sagittal section showing different position of cirrus (C.) and vagina (V.) in two segments of Otiditenia ewpodotidis. The cirrus sac among the Tetracotylea occurs in at least two types of structure. One, the most general, is typified, for example, by that seen in Stilesia and represented in a figure in Dr. Gough’s paper upon that genus and Avitellina, and discussed in a footnote concerning the cloaca genitalis. The second type, which is cer- tainly not so general, is seen in a genus Anoplotenia, the anatomy NEW AVIAN TAPEWORM. 209 of which I have lately given an account to this Society *. In the former type, as will be seen in Dr. Gough’s paper referred to, the cirrus sac contains a narrow cirrus which is protrusible from the sac and is of pretty well the same dimensions, through the sac not being at all wider at its free extremity. In Anoplotenia the cirrus-apparatus is divided into two regions; there is distally a protrusible sac of much greater calibre than the slender cirrus which is continuous with it posteriorly. The protrusible sac appears to be an ingrowth into the cirrus sac of the cloaca geni- talis. It is this kind of terminal male apparatus which we find in the tapeworm which forms the subject of the present com- munication to the Society. I have examined into its structure both by transverse and longitudinal sections, and have found that it presents certain differences from the cirrus sac of Anoplotenia. It has already been said, in describing the cloaca genitalis, that the end of the cirrus sac protrudes into that cavity ; how far it ean be protruded without any further temporary dislocation of its parts I do not know. It is evident, however, that, as with Anoplotenia, so in Otiditenia, there is a terminal section of this apparatus which can be protruded, though I have not met with specimens in which the protrusion is actually effected. 'Text- fig. 27 (p. 206) shows a longitudinal section through a cirrus sac that is seen in a transverse section of the proglottid con- taining it. It will be seen that the whole organ is of con- siderable size, though not so large proportionately as it is in Anoplotenia. It is, however, of much the same shape, being a slightly elongated sphere, though flask-shaped when fully retracted. The sperm-duct in this particular specimen approaches the cirrus sac from one side, and then sharply curves to enter it. The point of entry is at the extreme posterior end, 7. e. that furthest removed from the orifice of the cirrus sac into the cloaca genitalis, The sperm-duct is a good deal coiled within the cirrus sac and has clear slightly stained walls. It does not, however, become enlarged anywhere to form a vesicula seminalis. The transition between the sperm-duct and the cirrus is abrupt. The cirrus is not, however, of greater calibre, or at most of very slightly greater calibre, than the sperm-duct with which it is continuous. The abruptness of the transition lies in the fact that the walls of the cirrus are thick and very deeply stained and the lumen propor- tionately reduced. The cirrus is very much shorter than the section of the sperm-duct which lies within the cirrus sac ; it is slightly coiled. The cirrus itself again terminates abruptly in a wider sac. As will be seen in text-figure 27, this latter sac is flask-shaped, and, in fact, broadly corresponds in outline with the entire cirrus sac. The wider part of the flask lies within the wider part of the cirrus sac and the narrower part in the neck of the latter. The whole sac is composed of a deeply staining epithelium, * P.Z.S. 1911, p. 1003. Proc. Zoou. Soc.—1912, No. XIV. 14 210 MR. F. E. BEDDARD ON A which is quite continuous above with the lining of the genital cloaca and below with the epithelium of the cirrus sac. The epithelium appears to be quite the same throughout this whole tract. It is clear, in fact, that both the narrow cirrus and the flask-shaped pouch into which it opens form one structure possibly invaginated from the genital cloaca, which is quite distinet morphologically from the sperm-duct. The cirrus sac itself 1s algo divisible into two regions when it is occupied by the fully retracted cirrus, as shown in text-figure 27. The almost spherical distal part leads through a narrower neck to the cloaca genitalis. The spherical bulb is covered externally by a thin layer of muscle- fibres. The interior of the sac is filled with a tissue like that seen in the cirrus sac of other tapeworms, for example, in Anoplotenia, where I have represented its principal characteristics *. There are many nuclei belonging apparently to delicate muscular fibres and forming a padding tissue between the contained coils of the male efferent system. Running from the wall of the cirrus sac furthest from the pore are muscular slips which are attached to the nearest end of the wide sac into which the cirrus opens and are doubtless retractile in function. The narrower neck-part of the cirrus sac is tubular and has a much thicker coating of muscles, which are circular in direction. This layer is one with the thin muscular coat of the bulb-region of the cirrus sac. Between this thick muscular coating and the terminal part of the male efferent apparatus which lies within it is seen a delicate muscular layer with abundant interspersed nuclei like the packing tissue of the bulb of the cirrus sac. The fibres, however, have a definitely longitudinal direction, and would seem to be part of the retracting apparatus. It has been mentioned that the cirrus sac projects into the cloaca genitalis. The surface which thus projects is covered on that part of it which faces the external pore by close chevawx de frise of minute conical spines, which are not implanted hooks such as often occur upon the cirrus in tapeworms, but rather appear to be outgrowths of the cuticular covering. They suggest to some extent a comparison with a group of fine sete described by Fuhrmannt in the two species Anomotenia penicillata and A. isacantha in an apparently similar situation. The vas deferens immediately on leaving the cirrus sac forms a dense coil filling up a good deal of space. The tube is here wider than the sperm-duct within the cirrus, and the nuclei of the cells which constitute its walls are very obvious; the cells themselves are rather clear. I could find no vesicula seminalis along the course of the sperm-duct. The wierws of this worm, together with its contents—the ripe or ripening embryos—shows certain definite peculiarities. At its first appearance the uterus is sac-like and narrow, lying in front of the ovaries and testes but still not very near to the anterior # P. Z.S. 1911, p. 1015, text-fig. 215. + Centralbl. f. Bakt. u. Parasit. xlv. 1908, p. 516. NEW AVIAN TAPEWORM, 211 border of the segment. In this stage, when it is empty of eggs, it forms a narrow transversely running tube. In transverse sections of a slightly older uterus, such as that which is repre- sented in text-figure 24 (p. 201), the position of this part of the reproductive organs is seen to be remarkable. If such sections be examined from in front backwards, the uterus is the first part of the generative system to come into view ; for, although posterior in position in its segment, the uterus lies in front of the ovaries and testes. In such sections it appears first of all dorsally as a narrow and transversely elongated sac, not lying in the medullary parenchyma, but lying within the internal and circular layer of muscles which delimit the medullary parenchyma from the cortical layer—the body-wall of the worm. The uterus, so to speak, splits this circular layer of muscles into two layers, fibres being recog- nisable both dorsally and ventrally of it. It has probably pushed its way into this situation; but located there the appearance given is most suggestive of a coelomic cavity lying between the body-wall and a central hypoblastic mass comparable to the reduced gut of certain simple Planarian worms (e. g. Haplodiscus). In such sections, moreover, the lumen of the uterus is seen to be not quite continuous from side to side of the body. Muscular fibres run across dorso-ventrally, which are of the nature of strands rather than septa. These are plainly shown in the accompanying illustration (text-fig. 29). Moreover, the epithelial lining of the uterus is quite alone in these transverse sections, its nuclei being very deeply stained. This epithelial lining is continued over the strands of muscular tissue which partly divide up the cavity of the uterus. Although the uterus lies, as already said, below the dorsal parietes, there are hereand there a few outpocketings of the cavity of the uterus, spherical in form, which push their way into the thickness of the dorsal parietes. Each of these contained only one or two groups of ovarian and vitelline cells, and in the case of one uterus T only found two of these small blind outgrowths. These transverse sections also show another fact in the constitution of the growing uterus, and that is its increased dorso-ventral diameter laterally, both on the pore side and on the opposite side. These dilated regions of the uterus were rather more liberally traversed by transverse strands than the rest of the cavity. The lateral widening of the uterus is also very plainly to be seen in horizontal sections, where it is visible even in rather younger proglottids than those just referred to. These longitudinal horizontal sections (see text-fig. 25, p. 202) also show very well the extension of the uterus on both sides of the body up to but not beyond the large ventral water vascular tubes. The cavity of the uterus is thus apt to be a little shorter from side to side than the space occupied by the testes. On the other hand, when viewed in a series of longitudinal sagittal sections, the uterus will be seen to have a greater dorso-ventral extension than the space occupied by the testes. In the three figures (text-figs. 24, 26, 29), which show 14* I12, MR. F. E. BEDDARD ON A the gradual increase in importance of the uterus, it will be also observed that the total area occupied by the uterus and the rest of the generative organs diminishes in its proportion to the length of the segment in the older proglottids. It will also be noted that in the oldest proglottid figured (text-fig. 29) the testes are in course of disappearance. Text-fig. 29. Nearly mature proglottid of Otiditenia ewpodotidis, sagittal section. U. Uterus. In the ripe proglottids which are in course of being detached the condition of the eggs is remarkable in several ways. The NEW AVIAN TAPEWORM. VALI) segments, as has been pointed out in considering the external characters of this worm, are enormously swollen so as to be almost globular in form, except for the frill-like posterior end of each proglottid, where it ‘overlaps the one next in order behind it. It would be easily supposed that this tension of the proglottids is simply a matter of their being gorged with ripe eggs, such a dilatation of proglottids seen in other tapeworms being due to this cause. A microscopical examination, however, of such pro- glottids shows that this conjecture is wrong. By far the greater part of the interior of the proglottid contains no uterus or egg at all. Fully three-quarters of the area of the proglottid is quite empty of eggs, and the medullary substance only contains a few fragmentary remains of other parts of the sexual system—as I suppose, for I have not identified the vestiges in question with any certainty. Moreover, the dilatation is not due to the imbibition of fluid during the processes of preservation. It was as obvious in proglottids shed during the life of the bird as in those extracted from the gut after death. I have examined such proglottids in both transverse and longi- tudinal sections. Both sets of sections prove that the ripe eggs (or rather embryos) are only present posteriorly in the segment. In one proglottid, which was completely cut into sections and mounted upon ten slides, no less than seven of these slides showed no embryos at all scattered through the parenchyma ; in another proglottid, however, treated in the same way, embryos were found to lie in the more anterior region, though here also the most anterior part of the proglottid was devoid of eggs. In both of these specimens, however, and in several others which I have examined by means of sections, the ripe embryos or masses of embryos by no means occupied the whole of the parenchyma. There were large tracts of parenchyma quite uninvaded by the uterus or its remains. The fact that the masses of eggs may in some cases lie rather more anteriorly in the segment than they are apt to do in less fully ripe proglottids is, as I think, in favour of Dr. Benham’s view that a scattering of eggs takes place owing to a rupture of the uterus when the proglottids come apart *. The parenchyma in these ripe proglottids must now be considered, as its condition is doubtless related to the changes in the uterus that remain for deseription. In younger proglottids, such as those represented in text-figure 24, the parenchyma is firm in appearance, moderately stained by carmine, and with abundant very well-stained nuclei ; these nuclei seem to have a prevalently dorso-ventral arrangement in lines. Calcareous corpuscles are abundant, especially towards the posterior region of the segment, where the generative organs ave situated. In still older proglottids, which, however, are not yet detachable from the strobila, such as those represented in text-figure 29, the medullary parenchyma has taken on a * Quart. Journ. Mier, Sci. voi. xliii., 1900. 214 MR. F. E. BEDDARD ON A different appearance. It is much more distinctly fibrous than in younger proglottids, as is plainly shown in the text-figure just referred to. The fibres run, on the whole, dorso-ventrally, and thus appear transverse in sagittal sections. The fibrous appear- ance of the parenchyma is particularly obvious where the fibres are frayed out, owing to the breakage of the section. In such sections the caleareous corpuscles are still quite plain, chiefly massed posteriorly in each segment. And, finally, in proglottids of this age the uterus retains the perfect regularity of its shape. We may now revert to the ripe detached or quite easily detach- able proglottids. The same fibrous appearance of the medullary parenchyma is plain; but, owing to the swelling of the whole proglottid, the fibres no longer run entirely transversely in a dorso-ventral direction, but tend, in places at least, to be more circular in the way in which they lie. This is especially the case in the neighbourhood of the uterus. In these segments, however, we can no longer speak of a uterus like that of the earlier proglottids represented in the series of text- figures already dealt with (text-figs. 24-29). In the completely mature proglottids (text-fig. 30) under consideration the embryos are in partly or wholly detached masses of roughly spherical form consisting of more or fewer individual embryos. These spherical sacs, though of course vestiges of the uterus, seem to have no definite walls of their own, but to be bounded only by the fibrous tissue of the medullary parenchyma. There are comparatively few of them, and those so small as to contaih only one embryo are very few. The spherical masses of embryos are encircled by the fibres of the medullary parenchyma in such a way as to produce the impression of a definite sheath, which is perhaps particularly obvious in the case of two such masses lying close together. This statement applies to the larger as well as the smaller masses of ova. There is not, however, any very great development of this sheath, the character of its fibres being quite like that of the surrounding parenchyma. Otherwise, we might speak of par- uterine organs ; and, in any case, it is to be pointed out that we may have here just the commencement of the formation of paruterine organs, which is carried much further, but along the same lines, in such a genus as Thysanotenia*. I take it, how- ever, that there is nothing sufficiently definite to allow of the assertion that the present genus or species is to be characterised by the possession of paruterine organs. Before comparing the history of the development of the uterus in this species with that of other forms it will be necessary to follow the development of the contained eggs. In the uterus, when in such a stage of development as is represented in text-figure 24, there are comparatively few eges. In many sections the cavity of the uterus, which is not yet very spacious, is seen to be completely empty. When ova are present * See Beddard, “On Two Genera of Tapeworms,” P, Z.S. 1911, p. 994, NEW AVIAN TAPEWORM. 215 they are small and delicate-looking, and not accompanied by much interstitial matter. The uterus itself at this stage has not very marked epithelial walls. The appearance of the ova is, indeed, that of masses of the ovary transferred bodily to the uterus. Later on the lining epithelium of the uterus is quite obvious especially so far as concerns the nuclei of the same. In the uterus of this and some later stages the individual eggs (or embryos, as the case may be) are by no means always in close contact with each other. They are separated by and imbedded in a great deal of interstitial substance, which, as a rule, stains very faintly with carmine. Text-fig. 30. Mature proglottid of Otiditenia ewpodotidis, longitudinal section. U. Chambers into which the uterus becomes divided. It contains, however, a good many nuclei which do stain, and is thus evidently of a cellular nature. In the uteri of this 216 MR. F, E. BEDDARD ON A particular series of proglottids (shown in text-figure 25, p. 202) the accumulation of interstitial cells was chiefly in the uteral expan- sions close to the water vascular vessels. In these regions of the uterus the lumen was often entirely occluded by the densely packed contents. In the uterus of a later stage—that which is represented in text-figure 26-—the embryos were firmly imbedded in the interstitial substance throughout the whole organ, so far as I could see. This substance appears much denser in the uterus of these older proglottids—so much so that cavities are left here and there from which an embryo has fallen out in the course of preparing the sections, which preserve exactly the spheroidal shape of the embryo. The interstitial matter also seems to take stains more readily at this stage, but exhibits no nuclei and no structure that I was able to unravel. In the fully mature proglottids (see text-figure 30) this inter- stitial substance is still present, and the embryos are seen in the same way to be embedded in it, leaving cavities of exactly their shape when they chance to have fallen out. The interstitial sub- stance, however, appears here to be rather laxer and is not so deeply stained. It is very possible that this matter lying between the eggs is a source of food-supply for the growing embryos. In Avitellina centripunctata Gough has described the fact that the eges, after they have arrived in the uterus, ‘‘ become surrounded by smaller cells derived from the walls of the uterus,” as has been pointed out by Fuhrmann in the case of Stilesia sjistedti. These cells are figured by Gough* as lying between and apparently completely filling the interstices between the eggs. These cells have conspicuous nuclei and are held by Gough to perform a nutritive function with regard to the eggs. This final disposition of the uterus, or perhaps rather of its contents, in Otiditenia eupodotidis is not exactly like anything that is known to me at first hand or from the figures and descriptions of others. It is, however, suggestive of the figures that have been published of Monopylidium and even of Davainea. In his definitions of both of these genera (which are placed in separate families) Ransom } describes the fate of the uterus in almost exactly similar words: viz. “ Uterus breaks down into (numerous) egg-capsules, each containing one or more (several) eggs.” This is a little misleading in that the sharply contoured and thick-walled capsules of certain species generally assigned to the genus Davainea are different from the figures given of Mono- pylidium infundibulum ete. The definition would, moreover, apply to Otiditenia, in which, as I maintain, the conditions are really rather different from both. In several species of Monopylidium the ripe eggs are scattered and imbedded singly in the medullary parenchyma, so far * Gough, Quart. Journ. Micr. Sci. vol. lvi. pl. xiv. fig. 49. + “The Tenioid Cestodes of North-American Birds,” Bull. U,S. Nat, Mus. no. 69, 1909. NEW AVIAN TAPEWORM. 217 suggesting the genus Oochoristica *. Of MW. rostellatum Fuhrmann writes f that each egg is surrounded by “une parenchyme vacuo- laire qui forme ..... des cellules hexagonales.” This is repre- sented in a figure which suggests a definite limiting membrane to each of these “cellules,” and thus separating them from the general medullary parenchyma. In J/. cayennense, M. secundum, and M/. macracanthum the same author { finds the same singly imbedded ripe ova. And this condition appears to characterise some other species of the genus Monopylidiwm. There is, however, another species of tapeworm recently described from Gallinula chloropus under the name of “ Tenia marchali” by Mola §, which Fuhrmann || refers to the genus Monopylidium, in which the disposition of the ripe ova is rather different. Mola, in fact, figures the ova as not scattered singly through the paren- chyma, but arranged in groups of one to six. Furthermore, he does not represent the parenchyma surrounding them as vacuolar (as does Fuhrmann in his species), but as distinctly fibrous. The state of affairs is therefore obviously much more like that of the species with which | am concerned in the present paper. Mola, however, does not show any tendency for the fibrous parenchyma to enwrap the bundles of eggs such as I have described above in Otiditenia. There is, furthermore, no suggestion given of an epithelial lining to the cavities which lodge the eggs in M. marchali. Some important histological details are added by Clere 4] with reference to Monopylidium infundibulum. In this species we have, as it would appear, an agreement with M. marchali in the fact that several ova are lodged together in one lacuniform cavity of the medullary parenchyma. But these cavities are not isolated ; they form a complicated and irregular network of lacune**. Later still, however, the individual ova become more completely separated the one from the other, and the typical (¢) character of the genus Monopylidium is arrived at. It may also possibly be the case with IM. marchali. 1 have, how- ever, no reason to suppose that the metamorphosis of the uterus in my genus Oliditenia proceeds any further than is indicated in * Of, e.g., Beddard, P. Z. S. 1911, p. 633, text-fig. 150, e. + Rev. Zool. Suisse, t. xvi., 1908. { Centralbl. f. Bakt. Parasit. Bd. 45, 1907. § Bull. Ac. Belg. 1907, p. 886. || Die Cestoden der Vogel, Zool. Jahrb. 1908, Suppl.-Bd. x. §] Rev. Zool. Suisse, t. xi. 1903, p. 354. Ransom places this species in the genus Choanotenia on the grounds of his own observations as well as those of Cohn (Nova Acta Ac. Nat. Cur. Bd. Ixxix., 1901), which seem to show that the uterus is per- sistent “and possesses an irregularly lobulated cavity incompletely subdivided by infoldings from the wall.” This is, according to Ransom, a character of Choano- tenia, and contrasts with the breaking up of the uterus in Monopylidium, which I have referred to above. I may point out, in support of Clerc, that Cohn’s figure (loc. eit. pl. 32. fig. 47) may well indicate an incompletely mature uterus, since he represents in the same proglottid both ovaries and testes. In Otiditenia, at any rate, the ovaries and testes have disappeared when the uterus is fully mature. Cohn’s figure may correspond to a stage figured in text-figure 30 of the present memoir, ** Toc. cit. vol. xi. figs. 73, 77, 85. 218 MR. F. E. BEDDARD ON A text-figure 30. Clere also figures somewhat similar changes in the uterus of a species of Dilepis* (not named), where the scattered ova actually penetrate the cortical parenchyma. This fact I have also observed in Otiditenia. There are, therefore, clearly differences of importance between the ultimate fate of the uterus in the two genera—as I regard them—WMonopylidium and Otiditenia. In the former the eggs are in most (? in all) species finally scattered through the paren- chyma unaccompanied by any other cells such as occur with the ova in Otiditenia, in which genus the eggs are at the very end grouped into many more or less isolated but not well-marked capsules. There remains a comparison of the uterus of Otiditenia with that of Davainea. With regard to certain species of the latter there is no particular comparison possible. But Clere has figured the egg-capsules of Davainea frontinat, which do seem to present certain similarities to the egg-capsules of Otiditemia eupodotidis. In the former worm the egg-capsules differ from those of such a species as D. comitatus t in that the individual eggs do not lie closely together within the capsule, but are more or less widely separated with a good deal of interstitial matter between them, which the author regards as a part of the medullary parenchyma which has undergone alteration, This and the enclosed eggs is surrounded by a definite layer of cells, which are not to be looked upon as a part of the persisting walls of the uterus, since in that case they would not enclose a portion of the medullary parenchyma. If this interpretation of the facts be correct, there is clearly no possible correspondence with the phenomena which I myself describe in the present paper. It seems to me, however, to be not impossible that the supposed altered parenchyma-cells which lie amongst the ova are really the equivalents of the similarly placed cells in my genus Oéeditenia. Moreover, Ransom § speaks of cells accompanying the scattered ova of Davainea rhynchota. I am disposed, however, to think that there is another view to be taken of the egg-capsules of Davainea frontina, as figured by Clerc. From the account that he gives of them in the text and of the investigations of others on the same subject—to which we may add those of Leuckart ||—it seems clear that the egg-capsules correspond to the paruterine organs of a genus recently described by myself 4] under the name of Thysanotenia, as I have already suggested. In this case we cannot agree with the statement of Ransom, in defining the subfamily Davaineine, that the “ uterus breaks down into numerous egg-capsules.” For in Thysanotenia there is, I think, no doubt that the cases in which the eggs finally come to lie have nothing whatever to do with the uterus, and are, * Clerc, loc. cit. pl. xi. figs. 75, 76. + Loc. cit. pl. xi. fig. 80. { Ransom, Bull. U.S. Nat. Mus. no. 69, p. 17, fig. 8, cap. § Loe. cit. p. 14. || Quoted in Bronn’s ‘ Thierreichs,’ p. 1445, 4) P. Z. 8. 1911, p. 1000. NEW AVIAN TAPEWORM. 219 in fact, paruterine organs. This is not the case with the sacs of eges in Otiditenia. We may abstract from the foregoing account of the anatomy of this worm the following réswmé of its structural characters :-— Length about 3 inches; greatest breadth 4mm. Scolex with feebly developed rostellum with a marginal double circle of very numerous and small hooks. Suckers unarmed and rather large. Neck present and short. Proglottids broader than long, except “at the extreme end of the body, where they become rather longer than broad. Completely mature proglottids almost spherical, except for the frill which overlaps the following proglottid. ‘Two excretory tubes on each side, of which the ventral are very wide and the dorsal narrow; the two are at times parallel, but occasion- ally the dorsal tube is really somewhat dorsal in position. Ventral vessels joined by a wide cross-trunk at the posterior end of each proglottid. Generative pores alternate irregularly; the generative ducts pass between the dorsal and ventral trunks of the excretory system. ‘The generative pores are not borne at the end of out- growths of the proglottid. The testes lie at the extreme end of the proglottid and form a vertical wall of over 200 separate gonads, which, however, are included in a mass of medullary tissue rather different from the medullary parenchyma generally. The sperm-duct forms a large coil, and is also slightly coiled within the rather large cirrus sac. In the latter the actual cirrus is short and is connected with a wider (? eversible) tube also con- tained within the cirrus sac. The cloaca genitalis is deep. The ovary and vitelline gland lie in front of the testes. The vagina is furnished with a, lar ge receptaculum seminis. It opens into the cloaca genitalis behind and at right angles to the cirrus sac. The uterus lies in front of the ovary, and in mature segments the whole reproductive system is restricted to the posterior fifth or so of the proglottid. The uterus is a narrow transverse tube, wider at the two sides. Later it is broken up into several more or less spherical compartments. The eggs are imbedded, within the uterus, in a mass of cellular tissue whose origin is uncertain, and which later loses its cellular character, We have now to consider whether the species described in the present communication can be referred to any known genus or whether it will be necessary to form a new genus for its reception. The abstract of the anatomical characters that has just been given shows that the worm is undoubtedly a member of the large family Hymenolepidid or perhaps of the Davaineide. This conclusion need not be proved in detail. Furthermore, it is clear that the features which distinguish it, viz. the following assemblage of characters, necessitate its inclusion in one of the genera Mono- pylidium, Choanotenia, or Anomotenia of the Hymenolepidide, or to a new genus altogether. These characters are:—Armed rostellum and unarmed suckers; large number of proglottids ; alternate generative pores; absence of paruterine organs; testes behind ovaries; breaking up of uterus in ripe segments; and in 220 ON A NEW AVIAN TAPEWORM. a number of points which we shall have to consider in fixing the position of this worm. It is true that the three genera mentioned are separated by somewhat slender characters, which is emphasized by the fact that Choanotenia infundibulum has been referred by Fuhrmann to the genus Monopylidiwm, and that the same author has left the position of Choanotenia laevigata of Rudolphi in doubt. All the three genera, however, seem to differ from that which forms the subject of the present paper by the strong muscular rostellum and by the relatively small number of the hooks, arranged in a single or a double crown. Moreover, the seg- ments in representations of these genera are figured as con- siderably longer in proportion to their breadth than they are in Otiditenia. Finally (so far as concerns the more important point), the uterus appears to be a persistent and continuous sac in Choanotenia and Anomotenia, while the eggs in Monopylidium come to be scattered singly through the parenchyma. As I have endeavoured to show on a previous page *, the development of the uterus in Otiditenia is different. Nevertheless, I am disposed to place Otiditenia more nearly in the neighbourhood of these genera than in that of any others. With regard to the Davaineide the present genus does un- doubtedly show certain points of likeness to the genus Davainea, the definition of which genus is not, however, a matter of great ease. Otiditenia certainly lacks hooks upon the suckers, the existence of which in Davainea forms a part of its generic definition. But it must be remembered that D. lateralis from the mammal G'aleopithecus has suckers without hooks. The breadth of the rostellum and its numerous hooks is a point of similarity to Davaimea, in which genus the rostellum may be rather rudi- mentary (cf. Zschokke +), The principal reason, however, against assigning this worm from Hupodotis kori to the genus Davainea is the persistence of the uterus to the stage of the perfectly ripe proglottids, whereas in “the genus Davainea a definite functional uterus is not developed” (Ransom) £, and there are also paruterine organs. The generic § characters of Otiditenia will be, as I believe, the following :— Scolex with wide but rather rudimentary rostellum armed with over & hundred minute hooks arranged in two rows. Suckers unarmed. Neck present, not long. Proglottids for the most part wider than long, only as wide or slightly wider than long at the end of the body. Genital pores irregularly alternating. Detached pro- glottids very swollen, almost spherical. Water vascular vessels two pairs, ventral much the larger, nearly or quite lateral to each other ; transverse trunks also wide. Genital organs not mature very early * P. 210. + Centralbl. f. Bakt. u. Parasit. 1895, p. 634. { Bull. U.S. Nat. Mus. no. 69, 1909, p. 14. § I do not feel able to differentiate the specific characters. ON THE MILK-DENTITION OF THE RATEL. 22/1 im strobila. Testes numerous, at least 200 lying posteriorly in a thin vertical plate extending between water vascular vessels and even beyond them laterally, imbedded in interstitial tissue different from medullary parenchyma. No vesicula seminalis, sperm-duct with large coil; cirrus sac large, containing a looped part of sperm- duct, short cirrus, and an evaginable sac derived from cloaca geni- talis. Ovaries and vitelline gland in front of testes. Uterus in Jront of ovuries, a narrow transverse sac with cavity partly divided by ingrowing trabecule. Later uterus converted into several spherical sacs. Kggs thin-walled, surrounded by nutritive (?) cells. Hab. Hupodotis kori. The most noteworthy characters of the genus, so far as the external characters go, appear to be the rather wide and rudimentary rostelluin, which is, nevertheless, armed with very numerous though very minute hooks. The internal structure is remarkable for the restriction of the gonads to the extreme posterior part of each segment, and to the fact that the very numerous testes arranged only one deep are imbedded in a very different kind of medullary parenchyma, which is obvious to the eye on account of its feeble staining: by the peculiar form of the cirrus sac and the inclusion within it of an outgrowth of the genital cloaca, which is probably protrusible like the somewhat similar “‘ penis” of Anoplotenia: and by the fate of the uterus and the presence of interstitial cells lying among the eggs. 14. On the Milk-Dentition of the Ratel. By R. LypDEKKER. [ Received September 30, 1911: Read November 21, 1911.] (Text-figures 31 & 32.) Many instances are known among extinct mammals in which the milk-dentition presents primitive features entirely lost in the teeth of the permanent series. In the equine Merychippus, for example, the cheek-teeth of the milk-series are of the short- crowned cementless type of Anchitheriwm, whereas those of the permanent set show the high-crowned and cemented type cha- racteristic of the more specialised representatives of the family Kquide *. So far, however, as I am aware, no such atavistic features have been recorded in the case of any existing mammals ; and it is therefore of interest to bring to notice what appears to be a case of this nature. In the ninth edition of the ‘ Encyclopedia Britannica,’ Sir William Flower classed the Ratels (M/ellivora) with the Badgers in the subfamily Meline; this classification was followed in Blantord’s volume on Mammalia in the ‘ Fauna of British India’ + and in Flower and Lydekker’s ‘Study of Mammals’ ¢. * See Lull, Amer. J. Science, vol. xxiii. p. 177, 1907. + Page 175, 1888. { Page 576, 1891. De, MR. Re LYDEKKER ON THE When re-arranging, some fifteen years ago, the exhibition series of mammals in the British Museum I came, however, to the conclusion that this was incorrect; and in the label on the genus Mellivora 1 stated that although Ratels were generally classed with Badgers, it appeared, from thei peculiar type of colouring and the form of the upper molar, that they ought to be placed next the Tayra and Grison (Galictis) in the subfamily Mustelins, This revised classification (which renders the definition of the last-named subfamily more concise) was followed in the revision of Sir William Flower’s article ‘‘ Carnivora,” contributed by myself to the eleventh edition of the ‘ Encyclopedia Britannica,’ and likewise in my account of the Mustelide in ‘Harmsworth’s Natural History’*. It has also been adopted in Max Weber's ‘Siugetiere, who probably follows Winge in this respect. Text-fig. 31. Left upper dentition of Mellivora and Gialictis. A. Permanent teeth of Mellivora. B. 3; . Galictis. : C. Milk-, and some of the permanent, teeth of Mellivora. Thus matters stood till a few days ago, when I observed among a series of specimens sent to the British Museum by Miss Olive MacLeod from the Lake Chad district the skull of a Ratel in which the milk-dentition is just being replaced by the permanent set; the upper carnassial and molar being protruded, but the milk-carnassial being still retained, as are the milk-molars in advance of this tooth and the canines. * Vol. i. p. 513. In revising the 8th ed., 1906, of the ‘Guide to the Mammal- Galleries in the British Museum (Nat. Hist.),’ I unfortunately allowed Mellivora to retain its old position (p. 45). MILK-DENTITION OF THE RATEL. 223 In the permanent upper dentition of Ratels the carnassial (p. 4), in common with that of nearly all other living Mustelines, has the inner tubercle placed close up to the front edge of the tooth, while the molar (m.1) is characterised by the antero- posterior diameter of the inner half of the crown being greatly in excess of that of the outer half. In the milk-dentition, on the other hand, the carnassial (which in most Carnivora is a replica of the permanent one) has its inner tubercle placed near the middle of the blade; while, as I gather from another specimen, the inner half of the molar is much narrower than the outer, this tooth having, in fact, what may be called the typical carnivorous triangular form. Now in both the foregoing respects the aforesaid milk-teeth correspond in general characters with their permanent repre- sentatives in Galictis; the upper carnassial of that genus being peculiar among existing Mustelines on account of having the inner tubercle placed near the middle of the blade. ‘There are, of course, differences in regard to the details of these teeth, and also in respect to the orientation of the molar, when the milk- series of Mellivora is compared with the permanent set of Galictis; but the resemblance is such as to leave little doubt as to genetic affinity between the animals to which they respectively belong. And it would thus seem that the milk-teeth of the Ratel and the permanent ones of the Tayra represent a common primitive type, which has been superseded by a more advanced modification in the permanent teeth of the Ratel. Text-fig. 32. Outer side of left upper milk-dentition of Mellivora, showing the bifid or bicuspid canine. I find nothing very noticeable in regard to the hinder lower milk-teeth of the Ratel; but the upper canine has a distinctly bifid crown, as in certain Bats, and there are indications of a similar bifurcation in the corresponding lower tooth. Whether this is a primitive or a specialised feature, it is, in this case, difficult to say ; it is almost certainly the former in Bats. In referring to the teeth of Galictis as primitive in comparison with those of Mellivora, it should be mentioned that the comparison must be limited to those genera, as the permanent carnassial of Tertiary Mustelines, such as Plesictis, is of the Mellivora-Mustela type. That Mellivora is a more specialised 224 MR. J. LEWIS BONHOTE ON form than Galictis is evident, not only from the dental features already mentioned, but from the normal absence of the second lower molar (m.2) and likewise by the shortness of the tail and the disappearance of the ear-conchs; both the latter features being, of course, adaptations to a burrowing life. In connection with the absence of the second lower molar, it is interesting to note that in one specimen in the British Museum (No. 9.7.19.1) this tooth is retained on the left side. It is very small, like the corresponding tooth of Galictis, and had come into use before the carnassial was fully protruded, so that it would have been shed early. Although Galictis is now unknown north of Mexico, or thereabouts, it occurs fossil in the Jater Tertiaries of the United States; and this leads to the idea that Galictis and Mellivora are divergent members of a common stock which, like the Leopard (Felis pardus and FP. onca) and Ocelot (7. pardals, F. tristis, and F. nebulosa) groups, once inhabited a large area in Asia, whence it reached America by way of Bering Strait, and, having made its way into South America, died out in the north of the New World. 15. On a Further Collection of Mammals from Egypt and Sinai. By J. Lewis Bonnorr, M.A., F.L.S., VAIS [Received October 24, 1911: Read February 6, 1912. ] The following is an account of a small collection of mammals which has been sent home during the past two years by Capt. Flower. The most notable specimens are the Meriones crassus and Acomys russatus from Sinai, the type locality of these species. Apart from their extreme rarity in collections, the acquisition of these animals has enabled me to identify definitely the Meriones of Lower Egypt with Pomel’s JM. sellysti and also to describe the form found in the Sudan as a new race. The specimens of Acomys russatus prove to be quite different in size and colour from those obtained near Cairo by Mr. Nicoll and myself, which latter are therefore described under the name A. r. egyptiacus *. I must express my indebtedness to Capt. Flower and Mr. Nicoll for their kindness in allowing me to work out the collection and more especially for bringing home some of the specimens alive, and thus enabling me to carry on some observations and experi- ments on which I shall hope to have something further to record in the future. * The complete account of these two new subspecies appears here; but since the names and preliminary diagnoses were published in the ‘Abstract,’ No. 103, 1912, they are distinguished by being underlined.—Eprror. bo bo Or MAMMALS FROM EGYPT AND SINAI, RHINOLOPHUS ACROTIS BRACHYGNATHUS KX, Anders. Rhinolophus acrotis brachygnathus K. Anders. Ann. Mag. N. H. ser. 7, vol. xv. p. 73 (1905); Bonh. P. Z. 8S. 1909, p. 788. One specimen received from the Delta Barrage, 4th March, 1911. Crocrpura (CRoC.) RELIGIOSA Geoffr, Sorex religiosa 1s, Geoftr. Mém, Mus, xv. p, 128, pl, iv. fig, 1 (1827). Crocidura (Croc.) religiosa Is. Geoffr,; de Wint, in Anders, Zool. Egypt, Mamm. p. 168 (1902); Bonh, P. Z.S, 1909, p, 790. Two examples, both males, of this minute species were brought in from Aburoash near Cairo. Their measurements are as follows :— No. “ A.” Head and body 50 mm,; tail 37; hind foot 9; ear 7. No, “ B.” Head and body 55 mm,; tail 40; hind foot 10; ear 8. The skulls of both are in very good condition and show them to be quite adult. The skulls are identical in size, and measure : Greatest length 16 mm., greatest breadth 7; breadth across maxille 5; interorbital breadth 4; breadth of snont 2; tip of incisors to tip of large premolars 3°5, CANIS ZERDA Zimin, Canis zerda Zimm, Geogr. Gesch, ii. p, 247 (1780), Vulpes zerda Zimm. ; de Wint, in Anders, Zool, Egypt, Mamm., p. 233 (1902). 3d near Muut, Oasis of Dakhel, 9th May, 1911, This specimen was procured by Mr. Harding King, who has kindly presented it to the British Museum, MUNGOS ALBICAUDA Cuv. Herpestes albicauda G. Cuv. Régne Anim. ed, 2, i, p. 158 (1829); de Wint. in Anders. Zool. Egypt, Mamm, p. 193 (1902). Capt. Flower brought back a very young example of this species from Abu Usher on the Blue Nile, taken on the |st November, 1910. GERBILLUS PYRAMIDUM Geoftr, Gerbillus pyramidum Is. Geoftr, Dict. Class, H. N. vil. p. 321 (1825); F. Cuv. Trans. Zool. Soc. ii. p, 141, pl. xxv, figs. 6-9 (1838) ; de Wint. in Anders. Zool. Egypt, Mamm, p, 255 (1902) ; Bonh. P. Z. 5. 1909, p. 791. Three specimens of a large Gerbille said to have come from near Alexandria I have provisionally placed under this species, They are fully adult, but show a considerable range in size, the female being considerably smaller than the two males. From a com- parison of these specimens with the series in the British Museum it seems probable that there are several forms of this species, but Proc. Zeoi. Soc.—1912, No. XV. 15 226 MR. J. LEWIS BONHOTE ON the material at hand is not at present sufficient to admit of any definite conclusions being arrived at. The measurements are as follows :— 3. No. 358. J. L. B.: Hd.& b. 128 mm.; tail —; h.ft. 38; ear 17. é No. 359 J... B.: Hd G& b. 126 mm. ; tail 143; htt. 34 eansie 2. No. 360, J. L. B.: Hd. & b. 116 mm.; tail 143; h.ft.32; ear 17. Least supra- Length of Skulls Greatest Greatest orbital Basal Length of molar Sees est length. breadth. breadth. length. nasal. series. Sa Borskse Bh, Wien, 19 18 30 15 6 GMO SO aes, 20 8 30°5 15 6 ORS COM Some: 18°5 7 28 13°5 i) GERBILLUS GERBILLUS Oliv. Dipus gerbillus Olivier, Bull. des Soc. Phil. Paris, u. p. 121 (1801). Gerbillus gerbillus Oliv.; de Wint in Anders. Zool. Egypt, Mamm. p. 252 (1902); Bonh. P. Z. 8. 1909, p. 792. The collection contains two more of this pretty and common Gerbille, one from the desert near Giza and the other from the Khargeh Oasis. In spite of its wide range this species is remarkably constant both in size and coloration. MERIONES CRASSUS Sundev. Meriones crassus Sundeyv. K. Vet.-Ak. Handl. p. 233, pl. ii. fig. 4, craniuin (1843). Gerbillus sellysii Pomel, C. R. Acad. Sci. xii. p. 654 (1856). Meriones shawi Riipp.; de Wint. in Anders. Zool. Egypt, Mamm. p. 266 (1902) (partim). T have lately received from Capt. Flower an example of Meriones erassus from Tor in Sinai. As this species was originally described from Sinai, this example represents the typical form of the species. It differs from that found m Lower Egypt in being slightly larger, with a more pointed snout and a much longer and stouter tail. The Egyptian specimens recorded by me in a former paper agree well with a series from Tripoli in the British Museum, which are practically topotypes of Pomel’s sual) B00, 1] 2 ee wy 3 Notes on the foregoing Tables. I. General. The following calculations will show better what the figures on page 235 mean. On the average of the past three years, taking into consideration the different numbers of animals in each year, the figures for 1911 should have been, roughly :— 4 Noy ie(Clern Ste eae a agnciace qopeduanooncasocs 2020 Percentage of total deaths ............... 36 Ditto, excluding those animals which had not been six months in the Gardens ywakneet Veena pesca tet ett 20 So that the improvement is really much greater than appears from the mere figure-statement. IN THE GARDENS DURING 1911. 239 The principal percentage improvement is in the Mammals, which come out for 1911, as compared with the three previous years, roughly as 22 is to 31. The following table shows the deaths amongst the Mammals from the numerically most important diseases for the four years 1908-1911 :— 1908: 1909. 1910: “1911. Total number of animals .... 5608 5303 5540 6677 arberculosis e sedi. relies. 59 ye 18 18 Pneumonia: eh sedesee oe AZ 43 31 48 SOpticswilacivs: juss. cte cananss 12 15 7 a Broncho-pneumonia ......... 44 DI 50 4] Congestion of lungs ......... 29 38 4] 27 Gastro-enteritis . occu. .scseee 23 11 19 1s: HNGEOLIGIS: fo vdst oncceremsetor ent (2 46 32 39 RSS NIbIG él van: nd. dopateak 15 4 6 3 The Birds do not show any percentage reduction of mor ‘tality ; and the great relative mortality of birds in the Gardens is due, in my opinion, largely to the overcrowding of many of the aviaries. The Reptiles show the largest percentage mortality ; this is, in my opinion, partly due to the fact that so many of them arrive heavily laden with parasites of all sorts—some having as many as four different species—and partly to the present unphysiological method of feeding them. IT. Special. 1. The percentage of tubercle has fallen to hs per cent. in the Mammals, 13-3 per cent. in the Birds, and is 5-4 per cent. in the Reptiles, which is relatively less than last year all round. In 6 Mammals and 41 birds it was a general tuberculosis, In a Lion it was of the human type with cavitation of lungs, and in 7 Birds it was of bovine type. A remarkable case occurred in a young Duck three weeks old, in which the lungs, air-sacs, and kidneys were affected, and the growths were already caseating. 2. As before, all the mould-diseases are grouped here. In the Mammals—2 Wallabies and a Kangaroo—it was of the same type as described before, and due to the same organism. The percentage among the Birds remains unchanged: three cases were due to Aspergillus niger. 3. The deaths from pneumonia still remain very high, roughly about the same percentage as last year. My impression, from the post mortems, is that it is becoming more virulent in the xardens: there have been more secondary pneumococcal affections, 240 ON DEATHS IN THE GARDENS DURING 1911. such as enteritis, nephritis, and gastric ulceration. Many of the Mammals were very rickety and so predisposed. In three of the Reptiles it was due to worms: in all the other cases pneumo- coccal. 4, One, ina Japanese Ape, was due to pyorrheea alveolaris : the other two to deep abscesses. 5. Hight of these cases were due to pneumococcal infection. 6. In an Anoa, in which the liver was crammed with flukes. 7. The three birds had all syngamus. 8. Two of these were influenzal, and five had rickets. 9. Nine of the Mammals were badly rickety: in the Birds there was also, in most cases, cedema of the lungs. There has been a notable decrease of this condition in the Mammals and Birds. 10. The cause of this condition has been traced definitely in one instance, separately to shot, straw, grass, in two to sand, and in seven to worms. 11. The number of cases of enteritis is relatively about the same as last year. In the following instances the cause could be definitely traced: 15 were due to worms, 3 to flukes, 11 to decomposed food, 14 to sand, and 6 to foreign bodies. 12. This peowrredh in a Fox anda IResnoacien Devil. 13. The two cases in Mammals were in a Wallaroo and in a Kangaroo ; in both the primary growth was in the stomach : the former there were secondary deposits in glands and cael and in the latter in liver and glands. The reptilian case was a glandular cancer in the stomach of a Tortoise. 14. The two cases of sarcoma in Birds were ina Vulture and a Parrakeet respectively : in the former in liver, pericardium, and heart, and in the latter in the kidney. 15. The diseases grouped under the term ‘“ Malaria” were due in the greater number of instances to the Hamoproteus danilewskt, in the others to the Plasmodium precox. 16. This occurred in an Alligator after a compound fracture of the thigh. No. 108. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON. ‘ February 6th, 1912. E. G. B. Meapr-Watpo, Esq., Vice-President, in the Chair. The Minutes of the last Scientific Meeting were confirmed. The Secretary read a Report on the Additions that had been made to the Society’s Menagerie during the months of November and December 1911 and January 1912. Mr. E. G. B. Meapse-Watpo, V.P.Z.S., exhibited a mounted specimen of a pale fulvous variety of the common wild Polecat (Putorius putorius), belonging to the Rev. D. Edmondes Owen, of Llandovery, 8. Wales. ‘Ihe animal resembled in colour a well- known variety of the Badger, and was interesting because the Polecats in that particular district were frequently of this peculiar variety and had been well known locally for years. The Srcrerary read an account of some observations made at the Philadelphia Zoological Garden by Mr. R. D. Carson, C.M.Z.S., on an instance of retarded development of the foetus in a Red Kangaroo (Macropus rufus). * This Abstract is published by the Society at its offices, Zoological Gardens, Regent's Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘Proceedings,’ free ot extra charge. to all Fellows who subseribe to tke Publications ; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Sia Shillings per annum, payable in advance. 2 Mrs. Rost Haig Tuomas, F.Z.8., read a paper dealing with a breeding experiment with Pheasants undertaken to confirm a previous one, in which it had been observed that a male Pheasant had transmitted to his F 2 9 offspring the female plumage of his species. ‘The following cross produced the same result :— Phasianus Jormosus Q X Phasianus versicolor SG. ee eS x Ph. versicolor 3. | The five hens hatched in F 2 had grown up and were all versicolor in pattern, colour, dimensions, and moral character. One of these hens had been kept to breed with to test her purity, and the skins of the other four were exhibited together with the skins of a Ph. formosus Q and a Ph. versicolor Q for comparison. The results of these two experiments did not appear to conform to the theory that the cock was homozygous for sex ¢ ¢. These experiments had also shown that the male had not transmitted to his female F 2 offspring such constant purity of male plumage. In the first experiment, Silver x Swinhoe, out of four males three were “Si. Sw.,” one only pure “Sw.,” and the only two males that lived in the second experiment, formosws x versicolor, were both “ Fo, Ve.” Mr. J. T. Cunnincuam, M.A., F.Z.8., read a paper on Men- delian Experiments on Fowls. The paper described the characters of ten individuals of the F 2 generation reared from a pair of F 1’s produced by a cross between Silky @ x Bankiva g made by Mr. D. Seth-Smith. The characters recognised were seven in number—namely, colour of plumage, char. acter of plumage (whether silky or normal), comb, pigmentation of skin and internal tissues, toes (i.¢. presence or ‘absence of extra toe), feathering of legs, crest on head. The Silky of the original cross had white ‘ silky ” plumage, rose comb, crest on head, double hallux, feathered legs, and black pigmented skin. The Bankiva had black-red plumage of normal structure, single comb, unfeathered shanks, normal toes, and normal unpigmented skin, no crest. The dominant characters i in the F 1 were coloured plumage of normal structure, rose comb with crest, pigmented skin, feathered legs, and dewiblie hallux; but several of these characters showed irregular domi- nance or intermediate condition. The most important results recorded in the paper were imperfect segregation in the F2 generation in at least two of the characters—namely, the absence of pigmentation in the plumage and the absence of pigmentation 3 in the skin and tissues. The recessive white of the plumage occurred in four individuals, in all of which, but especially in one, some pigment was present. Only one specimen apparently re- cessive with regard to the absence of pigmentation in the skin had been examined post mortem, and in this unmistakable traces of pigmentation in the skin and peritoneum were observed. Mr. Cunningham criticised the recent paper by Profs. Bateson and Punnett, in the ‘Journal of Genetics,’ on the Inheritance of pigmentation of the Silky Fowl,and maintained that the evidence of these authors was not sufficient to prove that segregation in this character was complete in their experiments, and that there- fore their results were not necessarily contradictory to his own. In the absence of Mr. H. G. Primer, F.RB.S., E.LS., F.Z.8. Pathologist to the Society, the Sucrerary read a Report on the Deaths which had occurred in the Society’s Gardens during the past year. Mr. J. Lewis Bonnors, M.A., F.L.S., F.Z.S., read a paper on a further collection of Mammals from Kgypt, which he had received from Capt. 8. 8. Flower. The communication dealt with some twenty species, of which the following two were described as new :— Meriones crassus pallidus, from Atbara, Sudan, similar to M. crassus sellysii, from which it differs in its larger size, paler coloration, and more pointed snout. Acomys russatus egyptiacus, from the Desert near Cairo. A race of A. russatus, from which it differs in its smaller size and much yellower coloration. Mr. H. Wats Kew, F.Z.S., contributed a paper ‘On the Pairing of Pseudoscorpiones,” based on observations made by him on living specimens of Chelifer (Chelifer) latreillii Leach and Chelifer (Chernes) cyrneus LL. Koch. Fertilization was found to be effected, without intromission of a copulatory organ, by means of a spermatophore. The male and female faced one another in walking position, the male seizing with one or both palps one or both palps of the female. There was a period of courtship during which Chelifer 3 protruded at intervals long ‘‘ram’s-horn organs”; and Chernes 8, not possessing these organs, made peculiar movements with one of the palps and with certain of the legs. At length, the spermatophore—which differed in character in the two species—was extruded, and was affixed to the floor, in front of the female, where it stood erect or obliquely. The male then retired by taking a few steps backwards, the female at the same moment coming forwards and receiving the male-product from the spermatophore without delay. Con- trary to opinions previously held, the “ ram’s-horn organs ” took ‘no part in the act of fertilization; their function appeared to be excitatory. The modified legs of the first pair of Chelifer g 4 were found to be used for seizing the genital-opening of the female at the moment when the spermatophore was approached ; there was no corresponding action in the case of Chernes 3, in which the legs exhibited no marked modification. The next Meeting of the Society for Scientific Business will be held on Tuesday, February 20th, 1912, at half-past Hight o'clock P.m., when the following communications will be made :— 1, A. T. Masrerman, M.A., D.Sc., F.Z8. Notes on Age-determination in Scales of Salmonoids, with special reference to Wye Salmon. (With lantern illustrations.) a) _H. Tyson Jamuson, M.A., D.Sc. Ph.D. F.Z8. Studies on Pearl-Oysters.—I. The Structure of the Shell and Pearls of the Ceylon Pearl-Oyster (Margaritifera vulgaris Schumacher), with an examination of the Cestode Theory of Pearl Production. (With lantern illustrations.) 2 Se Eon ee Mimicry amongst the Blattide; with a Revision of the Genus Prosoplecta Sauss. 4. The Rev. O. Pickarp-CAmprines, F.R.S., C.M.Z.S. Contributions to the Knowledge of the Spiders and other Arachnids of Switzerland. The following papers have been received :— 1, Herpert L. Hawkins, M.Sc., F.G.S. The Classification, Morphology, and Evolution of the Kchinoidea Holectypoida. 2. H. G. Puimuer, F.R.S., F.L.8., F.Z.8. Blood-Parasites found in the Zoological Gardens during the four Years 1908-1911. 3. Dr. G. O. Sars, C.M.Z.8. Zoological Results of the Third Tanganyika Expedition, conducted by Dr. W. A. Cunnington, 1904-1906. Report on some Larval and Young Stages of Prawns from Lake Tan- ganyika. 4, Mrs. E. W. Sexron. Amphipoda from Bremerhaven. 5. Rospert Broom, M.D., D.Sc., C.M.Z.S. On the Structure of the Internal Ear, and the Relation of the Basi-cranial Nerves in Dicynodon, and on the Homology of the Mammalian Auditory Ossicles. 6. Epwarp W. SHAnn, B.Sc. Observations on some Alcyonaria from Singapore, with a brief Discussion on the Classification of the Family Nephthyide. 7. Georae H. Kenricx, F.ZS. A List of Moths of the Family Pyralide collected by Felix B. Pratt and Charles B. Pratt in Dutch New Guinea in 1909-10, with Descriptions of new Species. 8. THomas H. Wiruers, F.G.S. Some early Fossil Cirripedes of the Genus Scalpellum. 9, JuLIAN S. Huxury. A First Account of the Courtship of the Redshank (Zotanus calidris). 10. Frank E. Bepparp, M.A., F.R.S., F.Z.S. Contributions to the Anatomy and Systematic Arrangement of the Cestoidea.—IV. On Species of /nermicapsifer from the Hyrax and on the Genera Zschokkeella, Thysanotenia, and Hyracotenia. 11. Dr. BAsurorp DEAN. Additional Notes on the Living Specimens of the Australian Lung-fish (Ceratodus forsteri) in the Collection of the Zoo- logical Society of London, 6 Communications intended for the Scientitic Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Socruty or Lonpon, Recent’s Park, Lonpon, N.W. February 13th, 1912. No. 104. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON® February 20th, 1912. Dr. A. Smira Woopwarp, F.R.S., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed. Dr. A. T. Masterman, M.A., F.Z.S., gave a demonstration, illustrated by a large number of lantern-slides, of recent investi- gations on Age-determination in the Scales of Salmonoids, with special reference to Wye Salmon, Dr. H. Lysrer Jameson, M.A., D.Se., Ph.D., F.Z.8., read a paper “Qn the Structure of the Shell and Pearls of the Ceylon Pearl-Oyster (Margaritifera vulgaris, Schum.); with an Kx- amination of the Cestode Theory of Pearl Production.” ‘The author began by reviewing the work on the subject of Pearl Production carried out in Ceylon by Prof. Herdman, F.R.S., and his successors. He examined the theory, enunciated by Prof, Herdman, that most Ceylon “fine” pearls had for their nuclei the remains of cestode larve, and that these larvae, which are abundant in the liver and connective tissues of the Pearl-Oyster in Ceylon, were the “cause” of the most valuable pearls. Dr. Jameson maintained that the evidence adduced in support of this theory by Prof. Herdman and Mr. Hornell was insutfticient, and that the only drawings in Prof. Herdman’s ‘“ Report on the Ceylon Pearl-Oyster Fisheries,” published by the Royal * This Abstract is published by the Society at its offices, Zoological Gardens, Regent's Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications ; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in adyance, 8 Society, that purported to show the remains of cestodes in the centres of pearls, were capable of other interpretation. Moreover, he could not find in any of the pearls sectioned by Prof. Herdman, numbering some twenty-five or more, which Prof. Herdman had kindly allowed him to examine, a single instance of a cestode larva forming the nucleus. This observation was borne out by the results of the examination of between 300 and 400 pearls from Margaritifera vulgaris, mostly from Ceylon, but also comprising examples from the Persian Gulf, the Gulf of Cutch, the Mediterranean, Madagascar, New Caledonia, etc., none of which, on decalcification, showed cestode or other platy- helminthian larve as nuclei. The centre of such a pearl was (where it consisted of material other than the nacre or other normal constituents of the shell) nearly always composed of an abnormal form of shell-substance, analogous to that formed to repair an injury to the shell, which, owing to its opacity, might easily be mistaken for a foreign body. These repair-substances were sometimes associated with granular matter, the origin of which was obscure; this matter might perhaps be derived from the tissues, or might possibly be of parasitic origin, but Dr. Jameson saw no reason for regarding it as derived from a cestode larva. Dr. Jameson regarded the presence of these cestodes as a disease parallel to, but independent of, “ margarosis”; and compared the case of a pearl-oyster, containing both cestodes and pearls, to that of a man suffering simultaneously from echinococci and scabies, or of a dog infested at the same time with tapeworms and mange. The author then discussed the systematic position of these cestode larve. Prof. Herdman regarded them as a younger stage of a Tetrarhynchus larva, which also occurred in the pearl- oyster, and which, acting on this assumption, Shipley named Tetrarhynchus unionifactor. The adult of this worm occurred in the Ray (Rhinoptera javanica). Here, again, the author maintained that two parallel forms were confused, and that the larva which Herdman thought to be the cause of pearls was not a younger stage of Tetrarhynchus wnionifactor, but a species referable to T'ylocephalum or some allied genus. He had found a worm which might be the adult of this larva in the Ray (Aétobatis narinari). This supposed pearl-producing larva, and a similar smaller one, also found in the Ceylon Pearl]-Oyster, were described as new species under the names 7'ylocephalum ludificans and 7’. minus. Preliminary Descriptions. TYLOCEPHALUM LUDIFICANS, sp. 0. The worm supposed by Prof. Herdman to be the cause of “fine” pearls in the Ceylon Pearl-Oyster. Globular resting scolex, with conical, flattened, or concave myzorhynchus, 9 usually retracted within a muscular collar, which possesses a denticulated annulus. Average diameter 0°78 mm. ; musculature of the myzorhynchus showing no trace of division into bundles; collar-sheath usually widely open in the resting stage. Resting in fibrous connective-tissue cysts in the tissues of Margaritifera vulgaris from the Gulf of Manaar. TYLOCEPHALUM MINUS, Sp. n. Similar to the above but smaller, average diameter 0°14 mm. As a rule the myzorhynchus appears more conical than in 7’. ludificans, and the collar-sheath more constricted, with smaller aperture, in the resting stage. In some examples the musculature of the myzorhynchus shows a tendency to break up into bundles of fibres. Habitat as in 7’, ludificans. Dr. Jameson claimed that he had found 7'ylocephalum ludificans in specimens of the Ceylon Pearl-Oyster in Dr. Kellart’s collection in the British Museum, and had considered the possibility of their being concerned with pearl production, and dismissed the theory as untenable, previously to Prof. Herdman’s original departure for Ceylon. The second part of the paper dealt with the structure and formation of the shell and of pearls. The various repair- stbstances, which replace the ordinary shell substances under abnormal or pathological conditions, were described, their relations to the normal substances of the shell were discussed, and their occurrence in the pseudo-nuclei of pearls dealt with. The “caleospherules” which Herdman regarded as free concretions, and as the cause of “ Muscle Pearls,’ were considered to be in fact minute pearls, composed of the hypostracum, or special shell- substance to which the muscles are attached. This conclusion had been reached independently by Rubbel, in Marburg. The author said that his observations on the real cause and mechanism which led to the formation of pearls in the Ceylon Pearl-Oyster were still too incomplete to communicate; but he maintained that, as he had already laid down in his 1902 paper, the real cause of pearl production would have to be sought, not in the nuclei or pseudo-nuclei of pearls, but rather in the patho- logical conditions under which the tissues of the mollusc gave vise to the pearl-sac. It was only in a few cases, like the Trematode pearls in the common mussel, that the cause of the pearl-sac, i.e. in this case the trematode, frequently remained to form the “nucleus” of the pearl and tell the tale of its origin. The author had found that, as observed by Prof. Herdman, a minority of Ceylon pearls may have foreign bodies, such as sand- grains, in their centres. 10 Mr. R. Suetrorp, M.A., F.2Z.S., communicated a paper on ‘“Mimicry amongst the Blattide ; with a Revision of the Genus Prosoplecta Sauss.,” in which he dealt with a number of exceptions to this usually cryptically coloured type of Cockroach, and in greater detail with the Prosoplecta, nearly all the members of which presented a remarkably close and detailed resemblance to other insects. A paper entitled “A Contribution to the Knowledge of the Spiders and other Arachnids of Switzerland,” was contributed by the Rev. O. Pickarp-Campripcr, M.A., F.R.S., F.Z.8. It was based on a number of specimens collected for the author by various persons, at different times, and contained the description of one new species. The next Meeting of the Society for Scientific Business will be held on Tuesday, March 5th, 1912, at half-past Hight o'clock p.m., when the following communications will be made :— 1. Exhibitions and Notices. 2. Hersert L. Hawxins, M.Sc., F.G.S. The Classification, Morphology, and Evolution of the Kehinoidea Holectypoida. (With lantern illustrations.) Blood-Parasites found in the Zoological Gardens during the four Years 1908-1911. (With lantern illustrations.) 4. Dr. G. O. Sars, C.M.Z.S. Zoological Results of the Third Tanganyika Expeditior, conducted by Dr. W. A. Cunnington, 1904-1906. Report on some Larval and Young Stages of Prawns from Lake Tan- ganyika. 5. Ropert Broom, M.D., D.Sc., C.M.ZS. On the Structure of the Internal Ear, and the Relation of the Basi-cranial Nerves in Dicynodon, and on the Homology of the Mammalian Auditory Ossicles. 1. Epwarp W. Suann, B.Sc. 2. 3. 4. Jutian 8S. Huxtey. 11 The following papers have been received :— Observations on some Alcyonaria from Singapore, with a brief Discussion on the Classification of the Family Nephthyide. Grorce H. Kenrick, F.Z.%. Meera sa Mes T leet. A List of Moths of the Family Pyralide collected by Felix B. Pratt and Charles B. Pratt in Dutch New Guinea in 1909-10, with Descriptions of new Species. Tuomas H. Wiruers, F.G.S. Some early Fossil Cirri pedes of the Genus Scalpellum. A First Account of the Courtship of the Redshank (Z'otanus calidris). 5. Frank E. Bepparp, M.A., F.R.S, F.Z.8. 6. Contributions to the Anatomy and Systematic Arrangement of the Cestoidea.—lV. On Species of /nermicapsifer from the Hyrax and on the Genera Zschokkeella, Thysanotunia, and Hyracotenia. Dr. BAsurorp DEAN. Additional Notes on the Living Specimens of the Australian Lung-Fish (Ceratodus forsteri) in the Collection ot the Zoo- logical Society of London. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZooLoGicaL Socrety or Lonpon, ReEGENT’s Park, Lonpon, N.W. February 27th, 1912. ' A wane at, Wier’ me 4 j CY Baer ica a Rey 1 a A i Auer i a Ketan, See aE Asia pW ura Ti is Hyyl thy ‘ 7 ¥ Ww 1 hal é itt Gah hin ht Laka ae igre os 0,03 Bir tar a 0 ae ene Py ate a dap ie Wy iy t ' f \ Sor Lae a NEA om, hg \ oie, i ATA ite nants je ey "Sntkedestilt sh We hi tre Leh “ in Hiner Chis: SRE ARE EA Od aan alain ion Nae Basa No. 105. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON.’ March 5th, 1912. Sir Joun Rost Braprorp, M.D., D.Sc., F.R.S., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed. Mr. OuprieLp Tuomas, F.R.S., F.Z.S., exhibited the skull of a German Wild Boar from Baden and of a Hungarian Wild Boar from Kolozsvar, the latter recently presented to the British Museum by Friiulein Sarolta von Wertheimstein. The difference in size between these was so great that Mr. Thomas considered that the Hungarian Boar should be separated as a distinct species, which he proposed to call Sus attila. He also stated that the North and South Spanish Wild Boars were, on the other hand, so much smaller in different degrees than the German animal as each to deserve subspecific distinction from the latter. The three forms now described were therefore as follows :— SUS ATTILA, sp. n. Upper length of skull 452 mm.; height of skull on lower jaw 271. Hab. Hungary and Russia, Type locality Kolozsvar. Type. Male. B.M. No. 12.1.23.1 SUS SCROFA CASTILIANUS, subsp. n. Upper skull length 353 mm.; height 198. Hab. North Spain. Type locality Burgos. Type. Male. B.M. No. 11.10.5.3. * This Abstract is published by the Society at its offices, Zoological Gardens, Regent’s Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in advance, 14 Sus SCROFA B-ETICcUS, subsp. n. Upper skull length 324 mm.; height 208. Hab. South Spain. Type locality Coto Doinana. Type. Male. B.M. No. 8.3.8.12. Mr. H. L. Hawks, M.S8e., F.G.S., read a paper, communicated by Dr. Henry W Saeed “RRS V. P.Z.S., on “The Classifi- cation, Morphology, and Evolution of the Echinoidea Holecty- poida,” illustrated with lantern-slides. The classification of the Mesozoic Gnathostomatous Irregular Echinoids was revised, with diagnoses of the families, subfamilies, and genera, and a new genus and subgenus were introduced. The anatomy of the test was described for the Holectypoida, and compared with that of other Orders. The origin of the Irregular Echinoids was dis- cussed, and the lines of evolution that they followed were indi- cated and summarized in a genealogical table. Mr. H. G. Puimmer, F.R.S., F.Z.S., Pathologist to the Society, read a paper “On the Blood-Parasites found in the Zoological Gardens during the four years 1908-1911,” illustrating his remarks with a lar ge number of Jantern-slides. The paper con- tained the results of examination of the blood of 6430 animals, in about 7 per cent. of which parasites were found. Many of these parasites were described for the first time, and in other cases the hosts were newly recorded. Prof. G. O. Sars, C.M.Z.S., presented a memoir entitled * Zoological Results of the Third Tanganyika Expedition, con- ducted by Dr. W. A. Cunnington, 1904-1906. Report on some Larval and Young Stages of Prawns from Lake Tanganyik Four forms were dealt with in this paper, two of which repre- sented very early larval stages, and apparently belonged to two quite different kinds of Prawns, but owing to the difficulty of deciding with any certainty the species or even the genera to which they were referable, they were not named, although a detailed description was given and their probable origin sug- gested. The remaining two forms represented a larva in the last stage and a very young Prawn in the first post-larval stage, and both were referred to a definite species. Dr. Rosert Broom, D.Se., C.M.Z.8., communicated a paper “On the Structure of the Internal Ear, and the Relation of the Basi-cranial Nerves in Dicynodon, and on the Homology of the Mammalian Auditory Ossicles,”’ the first part of which contained an account, the first on record, of the bony labyrinth enclosing the internal ear and the nerve foramina in relation thereto, in the skull of the extinct Reptile, Dicynodon. The author had obtained a cast of the internal ear of a specimen in which the matrix was aa eo > i Al ate 15 hardened by epidote and the bone mainly calcareous. By dis- solving away the calcareous matter replacing the bone, he had satisfactorily traced the structure of the ear. The author stated that the vestibule was very remarkably elongated and that there was no trace of a cochlea. The semicircular canals were of the normal reptilian type. The homologies of the auditory ossicles were discussed, and it was shown that the bone which Dr. Broom had formerly regarded as the tympanic was really the stapes. In the light of his new observations the author stated that he was now prepared to accept the view that the incus is the homologue of the reptilian quadrate, the malleus the articular, and the tympanic the angular. The next Meeting of the Society for Scientific Business will be held on Tuesday, March 19th, 1912, at half-past Eight o'clock p.m., when the following communications will be made :— 1. A. Rapciyrre Duemore, F.R.G.S. Lantern Exhibition of Studies of Wild Animals in Africa and North America. 2. Epwarp W. Suany, B.Sc. Observations on some Alcyonaria from Singapore, with a brief Discussion on the Classification of the Family Nephtbyide. 3. Georce H. Kenrick, F.Z.8. A List of Moths of the Family Pyralide collected by Felix B. Pratt and Charles B. Pratt in Dutch New Guinea in 1909-10, with Descriptions of new Species. 4. Tuomas H. Wiruers, F.G.S, Some early Fossil Cirripedes of the Genus Scalpellum. The following papers have been received :— 1. JuuiaAn 8. Hvuxuey. A First Account of the Courtship of the Redshank (Totanus calidris). 16 2h Frank KE. Bepparp, , M. A,, alle RS. 7 HZ: S. Contributions to the Anatomy ad Sy stematic Arrangement of the Cestoidea.—IV. On Species of Jnermicapsifer from the Hyrax and on the Genera Zschokkeella, Thysanotenia, and Hyracotenia. 3. Dr. BasHrorD DEAN. Additional Notes on the Living Specimens of the Australian Lung-Fish (Ceratodus forsteri) in the Collection of the Zoo- logical Society of London. 4. Mrs. KE. W. Sexton. Amphipoda from Bremerhaven. 5. W. M. Smatiwoop and Euizasets G. CLARK. Chromodoris zebra Heilprin, a distinct Species. 6. C. Tate Racan, M.A., E.ZS. Descriptions of new Fishes of the Family Loricarnde in the British Museum Collection. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Society or Lonpon, ReGent’s Park, Lonpon, N.W. March 12th, 1912. or -I a 10. 11. 13. 16. _ On the Milk-Dentition of the Ratel. By R. Lyprxxer. (Text-figs. 31 & 32.) PAPERS. . Distant Orientation in Amphibia. By Brucu F. Cummines. (Text-figs. 4,5.) ..-.+- Some Remarks on the Habits of British Frogs and Toads, with reference to Mr. Cummings’ recent communication on Distant Orientation in Amphibia. by G. A. Boutmnamr, F.R.S., F.Z.8. «1 ee ee eee ee eee ee nies haeet at teats ; ee . Game Sanctuaries and Game Protection in India. i) E. P. Srzszine, F.L.S., F.Z.8., BR GSe ses eae er alenaneg Ih vapatans reerealr a ccral Ave share loa situ aittalclsreye ois Paradies Aiehierece Ga tsi . On the Moulting of an Arctic Fox (Vulpes lagopus) in the Society’s Gardens. By R. I. Pocock, F.R.S., F.L.S., F.Z.S., Superintendent of the Gardens, (Text-figs. 6-13.) . On the Moulting of the King Penguin (Aptenodytes pennanti) in the Society’s Gardens. By Davin Sera-Surru, F.Z.S., M.B.O.U., Curator of Birds. (Pl. I.) _ On the Presence of two Ovaries in certain British Birds, more especially the Falconide. By T. E. Gunn, BLS. (Pls. TLV.) 2 cence cciee ses cteten see ee eres pe Cee re On some Collembola from India, Burma, and Ceylon; with a Catalogue of the Oriental Species of the Order. By A. D. Iums, D.Sce., B.A., Forest Zoologist to the Government of India; late Professor of Biology, Muir College, and Fellow of the University of Allahabad. (Pls. VI.-XIf. and Text-figs. 14, 15.) ....++-- : . Ontogenetical Transformations of the Bill in the Heron (Ardea cinerea). By Prof. P. P. Susnxry, C.M.Z.S., Kharkov, Russia. (Pl. XIIL.)...... PINS Aine Regiee ‘ _ The Duke of Bedford’s Zoological Exploration of Eastern Asia.—XV. On Mammals from the Provinces of Sze-chwan and Yunnan, Western China. By O.prienp THomas, F.R.S., F.Z.8.....0+..05--: RTPI Wheels isrevaret there ate ee ISAC soe cover at Aarau oN ets The Freshwater Crayfishes of Australia. By Guorrrry Suirn, M.A., Fellow of New College, Oxford. (Pls. XIV.-XXVII. and Text-fig. 18.) Structure of the Alimentary Canal of the Stick-Insect, Bacillus rossii Fabr.; with a Note on the Parthenogenesis of this Species. By Aurrup E. Cameron, M.A, BiSe;, Fullerton Scholar of the University of Aberdeen and Research Student in the University of Manchester. (Pls. XXVIIL.—-XXX.)....-..+-+4-- Ber peek by. tes . Diagnoses of new Species of Terrestrial and Fluviatile Shells from British and German East Africa, with the Description of a new Genus (/wssoia) from Eusso Nyiro River, B.E. Africa. By H. B, Pruston, F.Z.8. (Pls. ».@.0.0 tgp. 0.0.4] aie Br Contributions to the Anatomy and Systematic Arrangement of the Cestoidea.—-III. On a New Genus of Tapeworms (Otiditenia) from the Bustard (Hupodotis kori). By Frank E. Bepparp, M.A., F.RB.S., F.Z.S., Prosector 'to the Society. (Lext-figs. 19-30.) a _ On a Further Collection of Mammals from Egypt and Sinai. By J. Lewis Bonnotr, MV A\,, Hn Sue ZSiicsrs aiecae Sis ye ae eiPetal eve eel er toter sakes Pel at earner nash hater ataa vet sare Report on the Deaths which occurred in the Zoological Gardens during 1911. By H. G. Pumner, F.R.S., F.Z.S., Pathologist to the Society . Pa ge LIST OF PLATES. 1912, Part I. (pp. 1-240). Plate Page I. Moulting of Aptenodytes pennanti ........065 ts eyes Monee 60 II. Paired Ovaries of Accipiter nisus and Falco tinnunculus .. \ III. Paired Ovaries of Circus, Falco, etc. -........06+ Sein Stas IV. Ovaries of : 1. Accipiter nisus. 2. Circus cyaneus. 3. Podi- & 63 COEDS CLISTATUS (5 weve 2 o's Wid SHON aad BOON TRL 5.0 : | V. Ovaries of Circus cyanews ss. ..% SE Se mee MCA ) VI.) VII. | VETS s TX. }'Onientiali@ollembola cies owe le cece ck ede ee eels wh cee, ere xX, | XI. | X11. / XIII. Development of the Bill in Ardea cinerea .veveeeesseees 125 RV ASHACOMSIS! 7772000277205.) oie seru lose tetsnetuloneheteraio vel Nic)sirs cl sim ereieieneis \ OVC eAStRCORSES FRURICLLIIG, P\n sucletain wig aiioetetnrG atic nines Bre aie GACT OVS: VAstadopsis Sanaa: (i cnis shes tie cies ee eRe etelo gle iste inna MOVER, > Astacopsis serratus, \O tic sci tiers she duwtaeetebe s sieievss sie hake XVIII. Astacopsis serratis, J se ceeeeeeacectaes BPA Weie/elciits) sien stare l ene \ Astacopsis hershawt; S oe. .cee cece alehefeie ctvalaveeeieu aie ines | XXI. Paracheraps bicarinatus, Gs... cece ee cee eee eee ewes XI. . Charaps tonuimants, Bi) vee s dese ieee be case sete we ria XXILL. Cheraps guinguecarinatus, Si. seees scene cece cede cant | XXIV. 1. Cheraps quadricarinatus, G. 2. C. intermedius, 3 ...- | XXV._ Astacopsis f rankl WA Peaern ete ee erm eer fer cutenaene XXVI. 7-11. Astacopsis franklinii, 12-14. A. serratus. 15-24. | Paracheraps RGR SAA GN IBISS AOS ASI 8 XXVIII. 25-29. Cheraps quinguecarinatus. 380). CL tenuimanus. 31-33. C. quadricarinatus. 34. C. intermedius ....2.., ) XXVIII. | : XXIX, | Alimentary Canal of Bacillus rosstt 2. ...6. cece eee eee 172 XXX. XXXT. \ New African Terrestrial and Pluviatile Shells............ 183 NOTICE. ‘The ‘ Proceedings’ for the year are issued in fowr parts, paged consecutively, so that the complete reference is now P. Z. 8.1912, p.... The Distribution is as follows :— ‘ Part I, issued in Mareh. Petra E18 Ud + June. et Re oe September. BA ee Bye December. « Proceedings,’ 1911, Part IV. (pp. 869-1213), were published on ‘December 15th, 1911. ‘The Abstracts of the Proceedings,’ Nos. 103 to 105, are contained in this Part. PROCEEDINGS OF THE GENERAL MEETINGS FOR SCIENTIFIC BUSINESS OF THE ZOOLOGICAL SOCIBTY OF LONDON, 1912. PART If. CONTAINING Paces 241 to 504, with 28 Puares AND 31 TExt-FIGURES. n | - / “ASti¢, : Vg 7 AUG 9 1917 +“) JUNE 1912. PRINTED FOR THE SOCIETY, SOLD AT THETR HOUSE IN REGENT’S PARK. LONDON : MESSRS. LONGMANS, GREEN, AND CoO., PATERNOSTER ROW. [Price Twelve Shillings. | LEST. OF WC ONE Nes: 1912, Parr II. (pp. 241-504). EXHIBITIONS AND NOTICES. Page Dr, A. T. Masrerway, M.A., F.Z.S. Demonstration of recent investigations on Age- determination in the Scales of Salmonoids .......... SF tigie te ob ote cncta hs eae 390 Mr. Ouprreip Tuomas, E.R.S., F.Z.S. The Races of the European Wild Swine: ........ 390 Mr. A. Rapcuyrre Duenworz, F.R.G.S. Lantern exhibition of photographie studies of wild animals in British East Africa and Newfoundland ................. Een 25: . ¥498 ~ Messrs. B. Gurrarp & Sons. Exhibition of the head of a cow Sable-Antelope, the skulls of an Isabelline Bear, a Leopard, and a Lion, all of which showed some abnormality.. 498 Mr. Orprietp Tuomas, F.R.S., F.Z.S. Two new Genera and a new Species of Viverrine Carnivora. (Text-figs. 61-63.) ....-- Ge NON ee aS! Tali Soke Steps keene Sonate ees 498 Mo. Guy Donuman. A new Snub-nosed Monkey. oc 000500. e uu slew «cle os eevee oleae Owes PAPERS. 17. Mendelian Experiments on Fowls. By J. T. CunninauaM, M.A., BZ.8.7 ca eeioee eee 18. Studies on Pearl-Oysters and Pearls.—I. The Structure of the Shell and Pearls of the Ceylon Pearl-Oyster (Mangaritifera vulgaris Schumacher): with an Examination of the Cestode Theory of Pearl-Production. By H. Lysrzr Jamuson, M.A., D.Sc., Ph.D, F.Z.S. (Pls. XXXITI--XLVII. and Text-figs. 83-41.) 0.0.06 ce pe enn ee eee ee eT) 19. Mimicry amongst the Blattide; with a Revision of the Genus Prosoplecta Sauss., and the Description of a new Genus. By Roserr Suenrorp, M.A., B.ZS. (Pl. XLVI. and Text-figs. 42-46.) 2. ca ceea cece ees e ce neces cece ccs cece nue em ates alge aoe 398 1 Contents continued on page 3 of Wrapper THE ZOOLOGICAL SOCIETY OF LONDON, Turs Society was founded in 1826 by Sir Sramrorp Rarruus, Mr. J. Sasine, Mr. N. A. Vicors, and other eminent Naturalists, for the advancement of Zoology and Animal Physiology, and for the introduction of new and curious subjects of the Animal Kingdom, and was incorporated by Royal Charter in 1829. Patron. HIS MAJESTY THE KING. COUNCIL. HIS GRACE TH" DUKE OF BEDFORD, K.G., President, Tue Kant or Atramont, F.S.A. Sire Jonn Rose Braprorp, K.C.M.G., M.D., D.Sc., F.B.S., Vice-President. Ricuarp H. Burns, Ese., M.A. Lr.-Cotr. Sire R. Havetock Cuarues, G.C.V.O., M.D. AtrreD Henrace Cocks, Esa., M.A. F. G. Dawrrey Drewitr, Ese., M.A., M.D. Crartes Drummonp, Ese, Treasurer. Sir Epwarp Duranp, Br., C.B. F. Do Cana Gopmay, Kse.,D.C.L., F.R.S. Srtr Epmunp G. Lover, Br., Vice- President. | Epuunp G. B. Merapz-Watpo, Ese., Vice-President. Prorrssor Epwarp A. Mrincuiy, M.A., F.RAS., Vice-President. Cuatmers Mrirenent, Esea., Ms,” B8e.,- LED. BRS: Secretary. W. R. Oeitvin-Grant, Ese. ALBERT Pam, Esa. iE: Aprran D. W. Pottocg, Esa. Oxprietp Tuomas, Ese., F.R.S. AntHony H. Wryeriexp, Ese. A.Suira Woopwarp, Esa.,LL.D., F.R.S., Vice-President. Henry Woopwarp, Ese., LL.D., F.RAS., Vice-President. 2 The Society consists of Fellows, and Honorary, Foreign, and Corresponding Members, elected according to the By-Laws. It carries out the objects of its foundation by means of the collection of living animals, by its Library, and by its Scientific Publications. The Office of the Society, Regent’s Park, N.W., where all com- _ munications should be sent, addressed to ‘The Secretary,” is open from Ten till Five, except on Saturdays, when it closes at Two p.m. The Library, under the superintendence of Mr. F. H. Waterhouse, is open daily at the above hours, except in September. The Meetings of the Society for General Business are held in the Meeting Room at the Society’s Office on the third Wednesday in every month of the year, except in September and Oeteber, at half- past Four o’clock p.m. The Meetings for Scientific Business are held in the Meeting Room at the Society’s Office fortnightly on Tuesdays, except in July, August, September, and December and January, at half-past Hight o’clock p.m. The Anniversary Meeting is held on the 29th. of April, or the nearest convenient day, at Four p.m. The Society’s Gardens are open daily from Nine o’clock until Sunset. Mr. R. I. Pocock, F.R.S., F.L.S., is the resident Super- intendent and Curator of Mammals, Mr. D. Seth-Smith is Curator of Birds and Inspector of Works, and Mr. E. G Boulenger is Curator of Reptiles. The Prosectorium for Anatomical and Patho- logical work is under the charge of Mr. Frank E. Beddard, M.A., D.Se., F.R.S., Prosector, assisted by Mr. H. G. 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Ladies or Gentlemen wishing to become Fellows of the Society are requested to communicate with “The Secretary.” P. CHALMERS MITCHELL, Secretary. Regent’s Park, London, N.W., June, 1912. MEETINGS OF THE ZOOLOGICAL SOCIETY OF LONDON FOR SCIENTIFIC BUSINESS. 1912, OES DA. OCTOBER nea e 29 a NovEMBER ...... 12 & 26 The Chair will te taken at half-past Light o'clock in the Evening precisely. ZOOLOGICAL SOCIETY OF LONDON. LIST OF PUBLICATIONS. Tue scientific publications of the Zoological Society of London are of two kinds—“ Proceedings,” published in an octavo form, and ‘‘ Transactions,” in quarto. According to the present arrangements, the “ Proceedings contain not only notices of all business transacted at the scien- tific meetings, but also all the papers read at such meetings and recommended to be published in the “‘ Proceedings ”’ by the Committee of Publication. -~ar SK - a) bt} tk Huth. Lith” London CEYLOM PEARL OYSTERS. P.Z2.8.1912 Pl, XXXVI. %, Huth Lath? London CEYLON PEARL OYSTERS. PZ. S.191e . PLS. Huth Lith? London. CEYLON PEARL OYSTERS. P.ZS1912.P1LXXXIX, Huth,Lith® London, ~ CEYLON PEARL OYSTERS. SZ. 18le Pik cob. CEYLON PEARL OYSTERS. biied , : AM aabaLa ee UA ease gee 29 & PZ.81912.PLXLI, J “ CEYLON PEARL OYSTERS. P.Z.S.1912.P1.XLI1. Huth Lith? London CEYLON PEARL OYSTERS. P26.1912e PLALM. o TLL. =>. Z —— ae Eee aa No SSS ; — y) au! (gine Aug ce 8 } \ S ip Lt Ht % W---------- Huth Lith’ London CEYLON PEARL OYSTERS. PA.o.1Lole PLAY. CEYLON PEARL OYSTERS. ‘SUALSAO THVad NOTAGD TPE TH P /, f > y fi f (MiMG: Lift ui pa ’ 1 | ‘S \ . SA ~ x a y \ PZS.1912.P1.XLVIL Huth Lith? London. H.L.J.del. CEYLON PEARL OYSTERS. PL.S Mi H.L.J. dei. CEYLON PEARL OYSTERS. THE CEYLON PEARL-OYSTER, 261 on the Pearl-Oyster fisheries of the Gulf of Manaar (16) I was in South Africa, and material for the examination of some of his conclusions, which I was unable to harmonise with my own observations made prior to my departure from England, was not available, Since my return J] have made use of all available material which is somewhat scanty ; and while it is insutlicient to enable me to propound, at the present moment, a working hypothesis as to the true cause or causes of the formation of Ceylon pearls, J think I have been able to show that the Cestode theory enunciated by Herdman, which has formed the basis of the somewhat meagre experiments which have been prosecuted in Ceylon since his return to England, and which even seems to have led to definite regulations slsowhere® , rests on quite insufticient evidence, and that, if the problem of the cause of Pearl-Production in Margaritifera vulgaris is to be solved, and a. scheme for increasing the productivity of the Oysters evolved, a fresh start will have to be made. The work that still remains to be done will centre around the causes which lead to the development of the epidermal sacs in which all pearls are formed—fine pearls and seed-pearls, “‘ muscle ”-pearls and ‘“eyst”-pearls (or, as 1 prefer to call them, “parenchyma”- pearls), and the mechanism which controls the secretion of conchyolin and the deposition therein of carbonate of lime. In fact, Iam led back to the principles enunciated by me in 1902 (25), that the essential element in pearl-formation is the pearl-sac, aud not the nucleus, and that it is by a study of the causes which lead to the development of the former that the problem of the origin of pearls is to be solved. Some material for these further investigations has just reached me as | write this introduction, and more is promised, but, owing to the difficulties and delays which may occur, | now publish my researches on the structure of the shell, and of pearls and their pseudo-nuclei and nuclei, without attempting to deal with the origin of the pearl-sac. I take this opportunity of expressing my thanks to the Ceylon ‘ompany of Pearl Fishers, Ltd., for purchasing, on my behalf, pearls in Colombo to be used in these investigations ; to Professor Raphael Dubois, for pearls from Magaritifera vulgaris trom the Mediterranean; to Prof. W. R. Dunstan, F.R.S., for allowing me to make use of material in the Imperial Institute; to Mr. J. Caleott Gaskin, Assistant Political Agent at Bahrein, Persian Gulf, for sending me, in 1903, a number of preserved specimens of the Lingah shell (JZ. vulgaris), some of which contained pears ; * Rules for Lower Burma under the Burma Fisheries Act, 1905. Rules 64 and 67, which prohibited the capture of Balistes and Trygon inthe Pearl Fishery districts, and required them, if accidentally caught, to be returned to the sea, appear to have been inspived by the Cestode theory. These rules were cancelled in 1909, It may be remarked that the Pearl-Oyster of Burma (the Mergui shell of commerce) is not the same species as the Ceylon Pearl-Oyster, I. vulgaris Schumacher, but is the great Mother-of-Pearl Oyster, IZ. maxima Jameson. 262 DR. H. LYSTER JAMESON ON - to Mr. E. Hopkins, of Hatton Garden, for specimens of Ceylon Pearls; to Professor W. A. Herdman, F.R.S., for specimens of Pearl-Oysters from Ceylon, and for allowing me to examine bis preparations ; to Mr. Max Mayer, of Hatton Garden, for specimens of pearls for my work; to H.H. the Jam Saheb of Nawanagar, for specimens of Pearl-Oysters from the Gulf of Kutch ; to Prof. L. G. Seurat, for pearls from New Caledonia, Madagascar, and the Gambier Archipelago; to Mr. A. E. Shipley, F.R.S., for allowing me to examine and make use of his specimens of 7'ylocephala and allied genera of Cestodes from Ceylon fishes; to Mr. KE. A. Smith, 1.8.0., for permitting me to make use of material in the British Museum (Natural History), including specimens from Dr. Kelaart’s collection; and to Mr. A. Van Noorden (of the firm M. Myers, Mother-of-Pearl Merchants) for specimens of Lingah and other shells. After this paper was handed in I received a copy of Rubbel’s paper (34a) setting forth in greater detail the results already published by him (33 and 34). Herr Rubbel and I have arrived, working independently on widely different molluscs, at identical conclusions on several important points, such as the nature of Herdman’s ‘“calcospherules.” Where practicable, I have inter- polated references to his work in the text, and my only regret is that it is not possible to discuss his valuable work more fully m the present paper and to dwell at length on the many points where, adopting a slightly different terminology and interpretation of the phenomena, our respective works lead to the same conclusions. (2) OUTLINE OF THE RECENT INVESTIGATIONS IN CEYLON. In January 1902 Professor W. A. Herdman went to Ceylon, at the request of the Colonial Office (who availed themselves of his services on the recommendations of the Council of the Royal Society and of Professor Ray Lankester), to investigate the condition of the Pearl-Banks. Professor Herdman took with him as his assistant Mr. James Hornell, who remained in Ceylon to carry on the work after the former’s return to England in April of the same year, and who collaborated in the preparation of Professor Herdman’s reports. Professor Herdman’s visit in 1902 gave him seventy-eight days in Ceylon, and was largely spent in an extensive biological and faunistic survey of the pearl-banks, carried out on two successive dredging-cruises, each of several weeks’ duration ; and he credits Mr. Hornell with the major part of the observations on Pearl-production (Royal Institution Lecture of March 27th, 1903) (14). Prof. Herdman himself always seems to have regarded the condition and welfare of the natural beds of oysters as a more important problem than the question of pearl-production (Report on the Ceylon Pearl Fisheries, Part I. p. 5, and Part V. p. 29; also Report of the Annual Meeting of the Ceylon Company of Pearl Fishers, Ltd, THE CEYLON PEAKL-OYSTER. 263 for 1908*). In fact, he contends on p. 30 of Part V. of his Report, and in his address to the Linnean Society on 24th May, 1906, that “to reverse the popular saying, if we attend to the prosperity of the bed as a whole, the individual oysters may be left to take care of themselves, both in regard to health and pearl- production.” In January 1904 Mr. Hornell was appointed Marine Biologist to the Government, to which post were subsequently added ‘the administrative duties of Inspector of Pearl-Banks. While holding these Government appointments Mr. Hornell continued to colla- borate with Prof. Herdman, though it is clear that the executive and administrative duties attached to his post interfered not a little with the more strictly scientific observations. Thus, in his Report on the Inspection of the Ceylon Pearl-Banks, November 1905, Mr. Hornell says (23), p. 6 :— “The working out of this material must of necessity await the long deferred time when a pause shall occur in the field work in which I have been engaged for the past eighteen months, and which permits me no leisure for the correlation and marshalling of biological data.” And, again, in Reports from the Ceylon Marine Biological Laboratory, } No. 1, p. 23, 1905, he says :— “The Marine Biologist should be given opportunity to further investigate the Mite of the spherical Cestode so abun- dant in the Pearl-Oy ator and which is the inducing agency in the formation of ‘cyst-pearls’ (‘fine pearls’ . The problem is far from solution, and will entail much unpleasant and trying labour before a satisfactory conclusion can be hoped for.” The observations of Prof. Herdman and Mr. Hornell on the spot were corrected and correlated by laboratory work in Liverpool, carried out by Prof. Herdman and his staff at the University, on the material sent home for investigation. » Prof. Herdman has courteously allowed me to examine the slides made during these investigations, showing sections of Pearls im sitw in the tissues, and of ‘the Gestode larvee which he asociates with pearl-formation. In March 1906 the Ceylon Company of Pearl Fishers, Ltd., was formed and the pearl-fisheries were leased to the Company by the Government, at a yearly rental of Rs. 310,000, the lease carrying the obligation to spend, in addition to the above rent, a sum of from Rs. 50,000 to Rs. 150,000 yearly ‘on the experimental or * Financial Times, Dec. 19,1908. Sir West Ridgeway, Chairman of the Company, on ae occasion said that “with regard to biological research, Prof. Herdman was of opinion that in the present condition of the Company’s pearl-banks accurate navigation, careful and exhaustive inspection of the ground, and wise administration are more important than the purely scientific side of the business.” 264 DR. H. LYSTER JAMESON ON practical culture of the pearl-oyster and on the improvement of the pearl-banks ” (50). On the formation of the Company Mr. Hornell was transferred to its service as local General Manager, Prof. Herdman being made Scientific Adviser. In April 1908 Prof. Herdman, at the request of the Company, paid another short visit to Ceylon, to enquire into the question of the inspection of the banks and other branches of the business. As a result of Prof. Herdman’s inquiries, the post of General Manager was abolished, being merged in that of Managing Director, and Mr. Hornell resigned, being succeeded by Mr. T. Southwell, A.R.C.Se. (Lond.), who since 1907 had been acting as Mr. Hornell’s assistant, and previously to that had assisted Prof. Herdman in his laboratory at Liverpool in the preparation of the material sent home for investigation. Mr. Southwell was made Scientific Adviser, a post which he still holds. Pro- fessor Herdman continued to be retained in an advisory capacity. Capt. J. Kerkham was appointed Superintendent of Fisheries*. Besides the work of the Company’s scientific employees, Dr. A. Willey, in his capacity as Marine Biologist to the Government (a post which he held along with the Directorship of the Ceylon Museum), has published some observations in the Ceylon Administrative reports and in ‘ Spolia Zeylanica.’ Particulars of the work done, and of the conclusions arrived at, by these several naturalists will be given in the course of the paper. In considering the incompleteness of the observations, despite the eight and a half years that have been devoted to the study of the Ceylon pearl-banks and the very large sums of money that have been expended, it must, of course, be borne in mind that for the last three or four years the banks are stated to have been practically bare of oysters t, and the prosecution of the investi- gations initiated by Prof. Herdman has thus been seriously hampered. But it is amazing that a Company whose prospects were so largely dependent on scientific work should have failed to set by an adequate stock of properly preserved material for scientific investigations and to establish at a suitable station a reserve of live oysters when the oysters were passing through their hands by the million. Had this been done, the barren years that have now come might have been devoted to the examination and amplification of Prof. Herdman’s observations, * Since the above was written the operations of the Company have ceased. It was announced in the ‘Times’ of April 4th, 1912, that the lease had been terminated, a deposit of £10,000 together with the property of the Company being forfeited to the Government. An examination of the causes of the failure of this short-lived Company, which started with a capital of £165,000, has lately been published by the present writer (26 a). + Not entirely ; for it was possible to obtain 12,000 oysters in Feb. 1910 for Mr. Southwell’s feeding experiment described in Part V. of the Ceylon Marine Biological Reports, p. 213, and no less than 35,000 oysters ranging from 8 months to 25 years old were obtained for the experiment described in Part IV. of the same publication, p- 169. Mr. Southwell, in a paper published in May 1911 (42), says: “The only bed which now exists is confined to an inshore area, and the oysters found thereon only rarely contain the pearl-inducing parasite.” ~ THE CEYLON PEARL-OYSTER,. 265 which of necessity were somewhat cursory and superficial. The result of this lack of foresight has been that the energy that ought to have been concentrated on an intensive study of the pearl= oyster and the mechanism of pearl-formation appears to have been largely dissipated on general faunistic work, such as the description of new species of crabs and tapeworms, matters which, valuable as they are from the purely scientific standpoint, have only a secondary bearing on the problem of increasing and rendering more reliable the supply of pearl-oysters and pearls. (3) Proresson Herpman’s ConcLustons oN PEArL-Formarion. Professor Herdman distinguishes several causes of pearl- formation, though only two of these are regarded as of sufficient frequency to have economic importance, viz. Cestodes, causing the majority of “eyst-pearls,” and ‘“ calcospherules,” causing “muscle- pearls.” I will pass over the pearly excrescences or “blisters ” on the inside of the shell, due to the irritation of boring animals or intruding particles of foreign matter, as these should be kept in a category entirely distinct from true pearls. The latter term, following my paper published in 1902 (25), I shall confine strictly to bodies developed independently of the shell, which are not in any way continuous with the shell, except where, owing to the rupture or absorption of the intervening tissues, they may become secondarily covered over with nacre continuous with the lining of the shell. When this happens to a pearl it becomes an “attached pearl,” a body quite other than a blister. Attached pearls are valued for the true pearl that can often be dissected out of them, whereas blisters are used as substitutes for pearls where the imperfect side can be concealed in the setting, e. g. in cheap jewellery, rings, pins, brooches, etc. Prof. Herdman (Report 1. p- 10) apparently applies the name “ ampullar pearls ” to blisters, that is to say to bodies “which are not formed within closed epithelial sacs like the others, but lie in pockets or ampulle of the epidermis,” and on p. 146 of the same part speaks of blisters as ‘pearls of an inferior quality,” but I cannot help feeling that, in scientific terminology at least, it is undesirable to apply the term pearl” to these bodies at all. Professor Herdman recognises the following causes of pearl- formation in the Ceylon pearl-oyster :— (i.) Grains of Sand and other Foreign Particles. These, in the experience of Professor Herdman and Mr. Hornell, only form the nuclei of pearls under exceptional circumstances. In the whole of their observations they have only records of three such cases out of hundreds of pearls examined (Report V. pp. 4 & 127). They say (V. p. 28) :— ‘* Probably it is only when the shell is injured, e. g., by the breaking of the ‘ears,’ thus enabling sand to get into the interior, that such particles supply the irritation that gives 266 DR. H. LYSTER JAMESON ON vise to pearl-formation. The ectoderm, in such cases, would probably also be damaged, and cells may be carried in with the inorganic particles.” As shown below, the presence of grains of sand and other foreign econ: ovens 8 ae particles in the nuclei of some Ceylon pearls has been confirmed by the present writer. (i.) Boring Animals. While recognising that pearly excrescences or “ blisters ” are mainly due to borers such as Zewcodore and Clione, Herdman and Hornell say (Report V. p. 28) that “in exceptional cases a free pearl may be formed in this way.” No specific instances, however, are cited, nor is any explanation suggested as to what would be the mechanism in such cases. (iu.) Parasites other than Cestodes. In his lecture at the Royal Institution, referred to above, Prof. Herdman said : “¢ We shall I think be able to show in our final report that Cestodes, Trematodes and Nematodes are all concerned in pearl-formation.” At the same time he recognised the ‘“ larval Cestode of the Tetrarhynchus form” as the most important cause. Again, in the Report (V. p. 29), Herdman and Hornell say : ‘“‘ A fuller experience is causing us to incline to the view that various parasites may act as pearl nuclei, even in the same mollusc. Some pearls are certainly formed around intrusive Nematodes. We have a complete cyst pearl, free and unattached, of which the nucleus is a coiled Cheiracanthus unctnatus, on which the pearl deposit is not sufficiently thick and opaque to obscure the coils so as to render identification difficult.” This pearl does not appear to be in Prof. Herdman’s collection. (iv.) Pearls without a Nucleus. Prof. Herdman points out that both in the case of the Ceylon Pearl-Oyster and J/ytilus some pearls have no trace of a nucleus (Report V. p. 18). He figures one such pearl from Mytilus, magnified 100 times. The existence of pearls without nuclei was recorded by Harley (11) in 1889. The observations set out below show that in the Ceylon Pearl-Oyster, both in muscle- pearls and in a great number of parenchyma-pearls, the presence of a nucleus of foreign origin is quite unnecessary, and point to the conclusion that the origin of the pearl-sac is usually due to stimulation other than that caused mechanically by such bodies. So far as J/ytilus is concerned, I attribute the conditions where THE CEYLON PEARL-OYSTER,. 267 a nucleus is absent to two alternative causes. In the first case, the Trematode described in my paper on the Origin of Pearls in the P. Z.8. for 1902 (25) may migrate out of the sac, in which a pearl without any nucleus, or with a nucleus consisting of a few residual granules, may subsequently be formed. In the second case, in certain localities, Wytilus edulis produces pearls through an agency (which I am at present trying to investigate) other than Vermian. These pearls may have as nuclei either a few dark granules or nothing that can be detected without the use of much higher magnification than 100 diameters. One of them is shown at Cin text- -figure 33 (p. 277). (v.) Musele-Pearls. The discovery of “‘muscle-pearls” was, I believe, first announced at the British Association Meeting in September 1903. Under this name (Brit. Assoc. Report, Southport, 1903, p. 695) Prof. Herdman distinguishes pearls formed “around minute calcareous concretions, the ‘ calcospherules, which are produced in the tissues and form centres of irritation.” They occur ‘“ most abundantly in the muscular tissue near the insertions of the levator and pallial muscles.” (Report, Part V. p. 27.) Herdman and Hornell say, speaking of muscle-pearls : “it seems probable that these have been formed by the deposition of calcareous matter around a minute calculus in the tissues” .... ‘The Muscle pearls when present are usually abundant, and when examining under the microscope a young pearl of this kind, im situ, it is common to find a large number of minute calcareous depositions or calco- spherules scattered in the neighbouring tissue. It is probable that the muscle pearls are formed around these microscopic calcospherules as centres of irritation, and as these [? their} positions are invariably in our experience close to the surface of the muscle or the mantle, there is no difficulty in under- standing that there, if anywhere, ectoderm cells might migrate to the source of irritation and thus be responsible for the deposition of a pearl.” (Report V. p. 27.) Muscle-pearls are especially numerous in certain localities ; Prof. Herdman instances (Report V. pp. 30-31) that they were particularly numerous on the 8.E. Cheval Paar in 1902 and 1903, and “that the vigorous and healthy oysters of the Eastern Cheval and Periya Paar Karai produce practically all the examples of this class of pearls,” the numbers produced on other banks being insignificant. Mr. Hornell, speaking of an examination of a number of pearls attached to the shell, states that ‘ decalcification of the pearls attached to muscle-scars reveals no organic nuclei, whereas the Jattached| pearls irregularly disposed have Cestode embryos as nuclei, exactly as ‘ fine’ pearls have.” (19, p. 12.) 268 DR. H. LYSTER JAMESON ON Mr. Southwell (40, p. 194), referring to the caleospherules causing ‘* muscle-pearls,” says : “The origin of the latter bodies is quite unknown, although it seems almost certain that they are depositions from the blood.” Again, in a later paper (42, p. 128), Mr. Southwell says “‘ Other pearls are also found in the Oyster, but they have no organic nucleus. Such pearls are termed muscle or seed pearls. ‘Their origin is obscure, but they are always found near the muscle insertions, and are believed to be formed round a calcospherule of excretory origin, or by the sheer of muscles moving in different planes.” In the first mentioned of the above papers (40), he goes on to say ‘“‘ Considerably more pearls are formed round calcospherules than round parasites, the ratio being about 13 to 1. They are therefore of considerable commercial importance.” Unfortunately, Mr. Southwell does not give the number or sources of the pearls on which this statement is based, although it is quite clear, from the observations of Prof. Herdman and Mr. Hornell, that ‘‘ muscle-pearls ” are characteristic of certain localities, and ‘‘cyst-pearls ” of others, and that the ratio may vary greatly on different banks. My own observations on “* Muscle-pearls” and on the nature of the so-called “ calcospherules” are given in a later part of this paper. (vi.) Cestode Larve. Of fine or ‘ Orient” pearls Prof. Herdman and Mr. Hornell claimed that the most frequent nucleus is a Cestode larva. In their ‘ Conclusions on Pearl-Formation” (Report V. p. 29) they maintain that their investigations have shown “that in Margariti- fera vulgaris, at Ceylon, the production of the ‘ Orient’ pearl is dependent upon Cestode infection and that the species mainly concerned is Tetrarhynchus unionifactor,” and in the General Summary of their Ceylon Report (V. p. 127) they say: “The majority of these fine pearls contain as their nuclei the more or less easily recognisable remains of certain Platyhelminthian parasites, which we identify as the larval condition of Cestodes belonging to the genus Vetrarhynchus.” It is stated several times that this supposed identification was made during Professor Herdman’s second cruise in March 1902, but its elaboration must have been, in great part, the work of Mr. Hornell at a later date. The narrative of the Cruise (Report I. p. 70), published in 1908, states, in a paragraph apparently inserted between the records of Mar ch 6th and 7th: ‘“TIn the intervals of dredging and when moving from place to place, we were now continuously engaged in THE CEYLON PEARL-OYSTER. 269 examining the parasites of the pearl-oyster and their influence on pearl-formation. We also decalcified such pearls as were found. This work was continued as time permitted during the next few weeks, and also by Mr. Hornell after I left. We found various parasites, in the liver especially, some of which were Platyhelminthian and others Sporozoan in their nature, and some of which were enclosed in caleareous capsules. Mr. Hornell afterwards determined that these were Tetrarhynchus larvee of Cestodes, and we have no doubt that they are in many cases the nucleus of the pearl, and the irritating cause of its formation,” Again, in the preface to Part IT. of his Report, p. vi, dated July 1904, Prof. Herdman says : “On the Cheval Paar, in March 1902, we satisfied ourselves that the ‘Orient’ pearl, free in the tissues of the pearl- oyster, is deposited around a cyst containing a Cestode larva, and preliminary notices to this effect were published in my Royal Institution Lecture of March 27, 1903, and at the Southport Meeting of the British Association in September 1903.” On p. 6 of Part V. of the Report (Pearl-Production), Herdiman and Hornell say : “One of the first facts that we were able to determine in connection with the Ceylon Pearl-Oyster, in the spring of 1902, was that the Orient pearl in the Gulf of Manaar is deposited around the young larva of a Cestode.” And on p. 15: “We found the Cestode larvee in association with pearls in the tissues during our cruises in the ‘ Lady Havelock’ in the Gulf of Manaar, in February and March, 1902. It was about March 6th (see Narrative, p.70,in Part 1.), when cutting up Oysters from the western part of the Cheval Paar, that we first became convinced that the opaque white globular larvee we were finding encysted in the liver belonged to Cestode worms.” On the other hand, Shipley and Hornell, in their paper on the Parasites of the Pearl-Oyster (Herdman’s Report, II.), seem to imply that at least the elaboration of these observations was carried out subsequently to Professor Herdman’s departure from Ceylon. Thus, they say (p. 79): “These larvee first attracted attention during the second cruise of the ‘ Lady Havelock,’ on March 6th, 1902, when numbers of the early globular stage were dissected out from the livers of oysters dredged from the West Cheval Paar. Subsequently, during the investigation carried out at the Galle Biological Laboratory, a second and more advanced stage of a Tetrarhynchus larva was found in the same 270 DR. H. LYSTER JAMESON ON material. Details of the morphology and histology were then worked out, and the relationship which the larve bear to pearl-formation was investigated.” Strange to say, Professor Herdman’s Preliminary Report to the Gover nment, dated J uly Ist, 1902 (18), makes absolutely no reference to the Hiscome: y in the previous March of this important aspect of the parasites of the Pearl-Oyster. In the Preliminary Report referred to, Prof. Herdman says (p. 2): ‘Samples of all the oysters obtained by us were examined for parasites and for any diseases or abnormal conditions, and although a considerable number of minute parasites, both Protozoan and Vermean, were found, still that is by no means unusual amongst molluscs, and we do not consider that we saw anything which gave evidence of any epidemic disease or widespread and injurious prevalence of parasites.” And again in the same Report (p. 4), in his summary of conclusions, the Professor says: ‘‘ A considerable number of parasites, both external and internal, both Protozoan and Vermean, were met with, but that is not unusual in molluses, and we do not regard tt as affecting seriously the oyster population.” (The italics are mine.) In view of the last three quotations, if it were not for the very definite assertions in Part II. p. vi, and Part V. p. 6, of Professor Herdman’s full report, quoted above, I should be almost inclined to think that, while the Cestode larvee were no doubt discovered ‘in association with pearls” during Professor Herdman’s cruise, the Cestode theory of Pearl-formation might have been evolved after Professor Herdman’s return to England, and after the above- mentioned preliminary report had been submitted. In that case Mr. Hornell might well have been misled by the false analogy of the case of the Trematode origin of pearls in Mytilus, which was dealt with at length in my paper (25). This paper appeared in August 1902; that is to say shortly after the Professor’s pre- liminary report of July 1st, 1902, containing no reference to the Cestode theory, was submitted. The view that my paper might have misled Mr. Hornell and Professor Herdman would also derive support from the fact that the real point of my paper had apparently been missed, viz. that it is not the presence of any parasite, but the specific stimulation of a narticular kind of parasite that causes the growth of the pearl-sac. I consider this point is by far the most important contribution I have so far made to the subject, and I believe it will be the basis upon which a rational system of artificial pearl-production will ultimately be built. The first announcement of Prof. Herdman’s theory of Pearl- formation seems to have been made at a lecture delivered before the Royal Institution on March 27th, 1903, an abstract of which appeared in ‘ Nature’ for April 30th of the same year (14). THE CEYLON PEARL-OYSTER. 271 (4) Examination or tHe Crsrope THEORY oF Peart-PRodUCTION. It is unfortunate that more figures of pearls containing as nuclei supposed Cestodes are not given in Prof. Herdman’s account of Pearl-formation. The only figures that represent the nuclei of decalcified pearls examined entire * as transparent objects appear to be those on plate ii. in the Section on Pearl-Production in Part V. of the Report, figures 5 and 7, figure 6 representing a dead Cestode in a partially calcified cyst (not, however, a pear). On p. 22 it is stated that these drawings, which are reproduced from Shipley and Hornell’s article upon the parasites of the Pearl- Oyster in Part II. of the Report, are the work of Mr. Hornell, and it is not evident from the text that Prof. Herdman had ever seen the specimens from which they were made. Turning to these same figures on plate i. of the article by Shipley and Hornell on the parasites of the Pearl-Oyster (Part Il. of the Report, figs. 5 (A) and 8 (B), (C), (D)), we find them described in the Explana- tion of the Plates as the nuclei of decalcified pearls; but the same figures are referred to in the text, p. 80, as representing the Cestode larva enveloped in its “ tough elastic and fibrous capsule of spherical form, derived from the adjacent connective tissue cells.” It is, I think, hazardous to identify these figures as the remains of Cestode larvee without examination of sections, and I cannot help feeling that each of these figures is capable of comparison with the non-Cestodian centres of pearls described by me below, It is a remarkable fact that nowhere throughout the Report is there figured a section of a decalcified pearl showing the Cestode remains in the nucleus, and to this fact I may add my own observation that of all the pearls sectioned in situ by Prof. Herd- man, numbering about 25 (not counting some minute clustered muscle-pearls), which he kindly sent me to examine, I could not find a single nucleus that I was able to accept as being a Cestode or other Vermian parasite. The characters of the nuclei in these preparations are described in the part of the paper which deals with my own researches. The superficial resemblance of the pearl figured on plate ii. fig. 4A, in Part II. (Parasites) of the Report, and again in Part V. (Pearl- Production), pl.i. fig. 5k, ¢, d, & e, to the globular Cestode larvee found in the Oyster is har ‘dly enough to go upon. If such a pearl consisted of a parasite thinly coated with nacre it would probably be dark and valueless and not a “fine pearl,” for the yellowish-brown dead tissue of the Cestode should be clearly visible through the nacreous coat. It is not stated whether this pearl was decalcified and sectioned to test whether the resemblance was more than “ skin deep.” * These figures are referred to by Southwell (42), p. 128, as “figures of sections of decalcified pears,” but they are not described as ‘such in the text; and they certainly appear to be no more than drawings of the centres of pearls ex xamined as transparent objects. DR DR. H. LYSTER JAMESON ON With regard to the mechanism by which the Cestode is supposed to cause pearl-formation, Prof. Herdman is unable to contribute much. He seems to recognise that the particular conditions necessary to transform the Cestode into a pearl-nucleus are not by any means universally present, and that it is only, so to speak, under exceptional circumstances that the Cestode, which is very abundant in the Ceylon Pearl-Oyster, becomes the centre of a pearl. The larva is surrounded by a connective-tissue cyst, and has not been satisfactorily demonstrated in any instance with an epithelial ‘* pearl-sac” (such as I described for the Pearl-inducing Trema- tode in Mytilus), though supposed proliferations of cells inside the connective-tissue cyst are figured in the Report (Part V. Pearl- Production, pl. iii. fig. 7). These, being inside a thick fibrous connective-tissue capsule, are difficult to accept as being equivalent to a pearl-sac, which I generally find to be surrounded by the spongy subepidermal parenchymatous tissue, except in the case of those parts of a ‘ muscle-pearl” into which muscle-fibres are inserted. From my own observations [ am rather inclined to regard these “cells” as granules excreted by the parasite itself, with possibly an admixture of wandering leucocytes. In any ease, if this 7s an epithelial pearl-sac, what becomes of the thick fibrous cyst outside it, which is certainly not present around the pearls @ Professor Herdman himself (see below) does not think the Cestodes enveloped in thick connective-tissue cysts are destined to become nuclei of pearis. The supposed migration of ectoderm-cells into the wall of a pearl-sac already formed and already containing a pearl, as figured in Part V. (Pearl-Production), pl. i. figs. 18-20, seems to be a matter quite apart from the question of the primary origin of the pearl-sac. On p. 23 of Part V. Prof. Herdman says :— “Tt is quite evident from the examination of a large series of sections, such as we have worked through, that the majority of these encysted parasites do not become encased in pearls. Probably none of those in thick connective-tissue cysts are destined to form nuclei. They are awaiting their legitimate further development in the next host, after their sheltering mollusc has been devoured by a fish. In such cysts and around such parasites we find no epithelial sac, and, as a consequence, there can be no pearl. Whether or not it is the case that only dead parasites supply the stimulus necessary to induce pearl-formation, and whether, as Giard has suggested, the parasites may be infested and killed by a species of Glugea, so that that Sporozoan comes to be even- tually responsible for the pearl, we are not prepared to say —we have found no fresh evidence in the Ceylon material bearing upon that point. It seems clear to us, however, that the epithelium is always associated with pearl-formation, and that in the absence of the epithelium only a thick-walled connective-tissue cyst is produced. If we adopt the view (see THE CEYLON PEARL-OYSTER. Dike below) that this epithelium is genetically related to the ectoderm, then a possible explanation of the difference in behaviour in the encysted condition would be that those larvee that carried in ectodermal cells become covered (when dead or while still alive) by a pearl-sac and embedded in a pearl, while those that were free from ectoderm become surrounded by the connective-tissue cyst.” No satisfactory instance, however, is recorded of the Cestode parasite being observed surrounded by an epidermal sac. Again in Part III. of the Report, p. 32, Professor Herdman, quoting a Report furnished to him by Mr. Hornell, says the abundance or otherwise of cyst-pearls “ is connected with the factors which control the relative abundance of the pearl-inducing Cestode and those which conduce to its death during encystment in suitable localities within the tissues—problems as yet obscure ” ; while in Part V.(Pearl-Production), p. 15, he says “it is appar- ently very difficult indeed to hit upon a stage showing the commencement of the pearl-formation.” And again, in an address delivered at the Anniversary Meeting of the Linnean Society of London in 1906 (17), Prof. Herdman, speaking of his Ceylon work, says that it is probably only those Cestodes that are provided with an ectodermal covering forming a pearl-sac that become the nuclei of pearls. But, as stated above, such an ectodermal pearl-sac has not yet been found to occur around the parasite, and its occurrence is purely theoretical. The investigations made subsequently to the publication of Prof. Herdman’s Reports have added little to our knowledge of the subject. In 1905 Mr. Hornell published a Report on the Placuna placenta pear|-fishery of Lake Tampalakamam, dated June 15th, 1905 (21). In this he states (p. 5) that he dissolved two Placuna pearls (out of five in his possession) and found that “in each case the nucleus proved to be the dead remains of a minute Platyhelminthian larva of the same stage and species as that which forms the nucleus of cyst-pearls in Margaritifera vul- garis.” Further study revealed the presence of Cestode larve in the dorsal portion of the visceral mass. He considers that these are identical in details of form and structure with those of Mar- garitifera vulgaris, but expresses some doubt as to their specific identity, and adds that if they prove distinct the Placuna parasite will need a fresh name. Mr. Hornell further observed that these larve multiply asexually by a process of endogenous budding, which he wrongly refers to as parthenogenesis. Mr. Hornell then goes on to make the following extraordinary statement, which I quote as giving some indication of the con- fusion of ideas which existed as to the identity of the supposed pearl-producing larve even in 1905, 7. e. nearly three and a half years after the beginning cf the observations :— “The discovery of a stage in the life-history of this parasite, which I am confident is homologous with the Proc. Zoou, Soc.—1912, No. XVIII. 18 274 DR. H. LYSTER JAMESON ON fedia-stage of a Trematode, confirms my original idea of it being a larval Trematode—an idea formed when first I saw it in March 1902” [7.e. the Cestode larva in Margaritifera vulgaris|. “* Other facts point to the same conclusion, and 1 have now no doubt on the subject. The genus to which it belongs is still doubtful, but as it is inconvenient not to have a name whereby to make mention of it, I shall henceforth refer to it under the cognomen of Distomum (¢) margariti- factor, n. sp., the specific name having reference to the fact that it is the inducing cause in the production of ‘ fine’ pearls.” Mr. Hornell anticipated that asexual reproduction would be found to occur in the Cestode parasites of Margaritifera vulgaris also, and this has since proved to be the case. An expurgated edition of the above report was published in 1906 (22), which, however, bore the same date, June 15, 1905, as the Sessional Paper. In this the statements as to the ‘supposed Trematode nature of the parasite were suppressed (though not formally withdrawn), the name “Distomum margaritifactor, n.sp., cancelled with a stroke, still figuring in the hthographed plate (Annexure IT.). As explained below (p. 345) I have been unable to confirm the presence of Cestodes in the centres of Placuna pearls from Ceylon, any more than I can find them in the pearls of Margaritifera v ulgari ws. In 1907 Dr. A. Willey (48) confirmed and extended Mr. Hornell’s observations on the endogenous reproduction of the Placuna Cestode. Mr. Southwell discovered (39, p. 173) that endogenous asexual reproduction or budding, similar to that described by Hornell and Willey in the parasite of Place. occurs occasionally im the Cestode parasites of the Pearl-Oyster. He only observed the occurrence twice, in November 1906 and January 1909 —in each case a single endogen was found. In 1903 the late Professor A. Giard (10) announced that M. L. G. Seurat believed that in the black-lipped Pearl-Oyster of the Gambier Archipelago (Margaritifera margaritifera var. cumingit Reeve) pearl-formation was due to the presence of a parasite, figures of which were given, and which Prof. Giard vereererl i, a genus near to C ‘yathophyllus | Cyathocephatus ?| Kessl. or Acrobothrium Olsson. Subsequently Seurat found the adult of this worm in the Eagle Ray (4étobatis narinari Kuphr.) in the spiral intestine, and named it Vylocephalum margaritifere (36). The adult, which is figured by Seurat (37), is quite a minute worm, not exceeding 4 mm. The scolex occurs in cysts, similar to those occurring in the Ceylon Pearl-Oyster, and multiple cysts (perhaps formed by bud- ding of the larva as in the Placwna parasites) occur also. Seurat THE CEYLON PEARL-OYSTER. ‘ 275 states that these cysts which form around the parasites become the nuclei of pearls, and a decalcified pearl shows an organic nucleus in the centre surrounded by concentric layers of conchyolin, the whole having a diameter of about a millimetre, and the nucleus being a scolex 225 mm. long and easily recognisable as that of Tylocephalum. It appears that in this case also the parasites may be present in great numbers without pearls being found (Seurat (35), 1904, p. 295). Here, again, examination of the scanty material available (see p- 346) has yielded no confirmation of the presence of Cestodes in the pearls of MZ. margaritifera var. cumingit. I am endeavouring to obtain further material from the Eastern Pacific, in order to extend my observations on this species. I may say that from the first time I read Professor Herdman’s Reports and papers on the subject I was sceptical as to the relationship of the Cestode to pearl-formation. Indeed, before Prof. Herdman’s departure for Ceylon, on examining Dr. Kelaart’s material at the British Museum, which Mr. E. A. Smith kindly placed at my disposal, I had detected the existence of these Cestode jarvee (which Kelaart seems to have regardedas “eggs of Entozoa”) in their connective-tissue cysts in the Ceylon pearl-oyster, and after having examined the larve, and also having decalcified pearls from the same oyster, dismissed the Cestode as probably not concerned in pearl-formation. My chief grounds for doubting the Cestode theory were the following :— (a) The absence of evidence that the Cestode ever occurred in an epidermal sac, and the fact that it was almost invariably sur- rounded by a fibrous capsule or cyst which does'not occur around the pearl. ui (6) The large proportion of the Cestodes that showed no sign of becoming pearl-nuclei, pointing to the conclusion that pearl- formation does not necessarily, or even normally, follow from infection. Thus, in a footnote to p. 12 of Part V. of his Report, Prof. Herdman says : ‘“* In comparing these statistics [7. e. of numbers of parasites and of pearls in Mytilus] with those of the Ceylon pearl- oyster, one is struck by the wholly different ratio borne by pearls to parasites in thetwo cases. In the mussels, pearls are far more numerous than the living parasites. In our Ceylon oyster, parasites may be exceedingly abundant * ; while pearls (cyst-pearls) are relatively very rare, probably not more than one to a hundred parasites.” * Mr. Southwell (42), p. 128, says: ‘‘ As many as 120 have been counted in a single oyster”; and further down on the same page: ‘‘ Occasionally several hundred oysters can be examined, each containing 20 or 30 cysts, and not a single pearl is to be found.” ‘ cS" 276 DR. H. LYSTER JAMESON ON In this connection an observation made by Dr. Willey (49) is very significant. Dr. Willey says :— ‘« A remarkable fact, indicating the subtle dependence of the pearl-producing molluscs upon their environment, is that whereas the most valuable pearls, called cyst-pearls by Prof. Herdman, are formed about a parasite as their centre or nucleus, yet the presence of these parasites in great numbers does not necessarily predetermine the formation of pearls. Pearl-oysters at Trincomalee may be heavily infected with the parasites without yielding pearls. It may be said that the parasitic infection and the pearl-disease are two separate phenomena, the latter proceeding from the former under certain conditions which are realised in the Gulf of Manaar. Whether these exact conditions can be reproduced elsewhere is one of the main problems before the Company. In the same way the cultivation of the oysters and the multipli- cation of pearls are two separate operations, the latter proceeding from the former in response to certain conditions affording the suitable stimulus. Conditions may favour the bivalves, but not their parasites; or they may favour both hosts and parasites, but not the production of pearls.” (c) Professor Herdman’s statement on p. 17 of Part V. of his Report that Mytilus pearls (which he examined in order to be able to correlate his work with mine) differed from Ceylon pearls in “the large size of the nucleus in the pearl (where a nucleus is present) and its characters, which are quite different from those of the encysted parasites in the Ceylon Pearl-Oyster.” Now the nucleus of a A/ytilus pearl is generally about 0°5 mm. in diameter— the size of the Trematode when contracted into a sphere. As the Ceylon Cestode-parasite measures roughly from 0:5 to 1 mm. in diameter, the nucleus of a Ceylon pearl, if composed of its calcified remains, should if anything be larger, rather than smaller, than that of a Mytilus pearl. And the characters of the nucleus should not differ greatly—the dark opaque yellowish or brownish substance formed by the decomposition and subsequent calcification of the parenchymatous and muscular tissues of a Trematode should not differ materially in appearance from the analogous remains of a dead Cestode. For purposes of comparison I figure below (text-fig. 33, A & B) a Trematode pearl from J/ytilus, from Foulney, Lancashire (Preparation CIII). A shows the pearl decalcified and examined entire in oil of cloves, B shows the nucleus in section. In both cases the foreign nature of the nucleus is obvious, quite apart from the fact that in this preparation its Trematode character is quite clear (which would, of course, not be the case where decomposition had advanced considerably before calcification commenced). The characters of this nucleus are quite different from those of the pseudo-nuclei of Ceylon pearls figured in the THE CEYLON PEARL-OYSTER. PART ( plates, the concentric stratification of the majority of which never occurs in a ‘Trematode nucleus, and could hardly be expected in a Cestode. Text-fig. 33. A Mytilus pearl, from Foulney, near Piel, Lancashire, with a Trematode nucleus : A, examined entire in oil of cloves, after decalcification : B, the same in section. In A the oral sucker and digestive cxca of the worm are distinctly visible. In B the internal anatomy is still preserved. cu., cuticle; sp., spines on same; dig., digestive cecum ; skr., ventral sucker; at dand q ave dark masses, which may well represent the remains of the yolk-glands and gonads; nac., nacre. C,a Mytilus pearl of non-Trematode origin, from Plymouth. Here the nucleus is, as in many Ceylon pearls, a minute group of granules. A X 20; B X 70; C x 20. As Mr. Cyril Crossland, Marine Biologist to the Sudan Govern- ment, is quoted by Professor Herdman (Report Ceylon Pearl Fisheries, Pt. V. Pearl- Production, p. 3) as supporting the Cestode theory, so far as MW. vulgaris in the Red Sea is concerned, I wrote to him to ask him for further information. He replied, in a letter dated December 9th, 1911 :—*I never published any state- ment that Cestode larvee caused pearl-formation in the Red Sea. The evidence to my mind is in need of revision. In all cases the first result of excessive stimulation of the secretory epidermis of the mantle is the formation of a dark brown horny material [?.e. my amorphous substance.—H. L. J.]. How would this stain in sections, and is it cellular like the horny material of the prismatic layer? If so, would not a shrunken nucleus of such material resemble the dry remains of a Cestode? This is a criticism which I have had in mind several years, and have never put it to the test.” From this it is clear that Mr. Crossland, though cut off from the possibility of applying modern laboratory technique, has arrived at much the same conclusion as that which I am elaborating in this paper. To summarise the supposed relation between Cestodes and 278 DR. H. LYSTER JAMESON ON Pearls, as described by Professor Herdman and Mr. Hornell, the position is briefly this :— ‘1) Ceylon Pearl-Oysters were found to contain large numbers of Cestode parasites which occurred simul- taneously with pearls, but which did not necessarily result in the formation of pearls. (2) The nuclei of the majority of “ cyst-pearls” were thought to be identified as consisting of the remains of these parasites, though Mr. Hornell’s figures of such nuclei are capable of other interpretation. (3) No satisfactory evidence was adduced of the Cestode having acquired a surrounding epidermal sac, such as is normally formed around the pearl-producing Trematode in Mytilus, though Prof. Herdman admits that this sac is essential for pearl-production. ‘The first stages in the supposed process are therefore purely hypothetical and unsupported by observation, besides pre-supposing an abnormal departure from the parasite’s usual habit. The evidence in favour of the theory is mainly that the more highly infected the oysters are with these particular Cestodes, the richer they are in pearls. Thus it was observed in 1904 (Report III. p. 32) that the oysters from the North-West Cheval, besides being the most extensively infected with Cestode-cysts were also the richest in cyst-pearls. And, again, Mr, Southwell records (40, p. 194), that “the infection of the very old oysters | with tapeworm-cysts | found on the Kondatchi Paar in 1908 was remarkably low, and, as bearing practical proof that infection and pearl yield are intimately connected, it is interesting to note that the pearl yield also was remarkably low, the valuation only working out at about Rs. 18 per 1,000 oysters.” These facts might be explained, however, on the assumption that the conditions favourable to pearl-production are also favour- able to Cestode infection. Characters, Identity, and Life-Histories of the Cestode Parasites of Margaritifera vulgaris. Apparently the first announcement of the supposed relation between the Cestode and pearl-production was made by Prof. Herdman at his Royal Institution lecture on March 27th, 1903 (14). Inthis he says that he and Mr. Hornell have proved so far ‘that in Ceylon the most important cause is a larval Cestode of the. Zetrarhynchus form.” Again, in the Report of the British Association, Southport, 1903, p. 695, Prof. Herdman says: ‘‘ The parasite in the case of the majority of the cyst-pearls of Ceylon is the larva of a Cestode which appears to be new, and will be described under the name of ‘ Tetrarhynchus unionifactor’ and the pearl-inducing parasite is referred to throughout Prot. Herdman’s Report under this name. THE CEYLON PEARL-OYSTER, 279 But the worm specifically described by Shipley and Hornell as 'etrarhynchus unionifactor ou p. 88 of Part IT. ‘of Prof, Herdman’s a (Parasites of the Pearl-Oyster) and figured in plate il. figs. 19 & 20, is a well-advanced Tetrarhynchus 65 to 7 mm. long, which occurs in and around the intestine of the Pearl- Oyster; and, to say the least of it, it is doubtful whether this worm isa later stage of the globular cysts, which Prof. Herdman identi- fied as the nuclei of pearls, and not an entirely distinct organism. In order to avoid confusion of terms I am therefore giving separate names to the larger and smaller globular Cestode larvee which Herdman recognises, as it is caleulated to lead to much confusion of issues if Frese are referred to by the name of T'etra- rhynchus unionifactor before their identity with it can be demon- strated more satisfactorily. The arguments for regarding the supposed pearl-producing parasites as distinct from TVetrarhynchus unionifactor are set forth below. In the absence of satisfactory evidence of their relation to the genus 7etrarhynchus, | propose, following Seurat (36), to whose larval Cestode, mentioned above, they bear a close resemblance, to refer them to the genus 7'yloce- phalum* and to describe the larger and smaller forms respectively as T'ylocephalum ludificans, sp. n., and T'ylocephalum minus, sp. 0. Two well-marked sizes occur in these globular larve and they are regarded by Herdman as distinct organisms (Report V. p. Bay. On the other hand, Southwell coneiders that the asexual repro- duction, which he has occasionally observed, accounts for the varying sizes of the larve in the Ceylon Pearl- -Oyster, and says ‘‘T am now convinced that these different sizes merely represent the same species in different grades of development.” | am inclined to share Prof. Herdman’s view that these two sizes are distinct organisms. It may even prove that there are more than two species represented. Jndeed, I should not be surprised if further research on fresh material were to show that both 7'ylocephalum ludificans and 7’. minus are composite species. Professor Herdman regards 7’, ludificans as the earlier stage of Tetrarhynchus unionifactor, and calls attention to its re- semblance to Van Beneden’s ideal figures of the young of Tetrarhynchus, while he treats 7. minus as another species of Tetrarhynchus in its earlier stages. Nevertheless, he seems to have had suspicions that some, ‘at least, of these larvee might be Tylocephala, though he appears in the end to have decided that they—and presumably with them Seurat’s larva—are a hitherto unknown stage in the life-history of the genus Tetrarhynchus. In the Preface to Part II. of his Report he says (p. vi) :— “Tt is possible that some of our Ceylon Pearl-Oyster Lape may also belong to the genus Acrobothrium’ .e. the genus to which Sans at’s larva was then referred |, a ‘although. the more advanced ones are certainly Tate rhynchids ” ; * J,inton (27 a). pp. 805-9, pl. ix. figs. 5-9. Type 7. pingue, from spiral valve of Rhinoplera quadriloba. 280 DR. H. LYSTER JAMESON ON while in Part V. of the Report, p. 14, he and Hornell say :— ‘“‘Some of our Ceylon Pearl-Oyster parasites very closely resemble the figures given by Giard” [7. e. of Seurat’s larva] ‘“and possibly may also belong to the genus Cyathocephalus | Tylocephalum|, although most of them are certainly Tetra- rhynchids ” ; and on pp. 16-17: ‘““Tt is possible, however, that more than one species of Cestode is represented—one is certainly a species of Tetra- rhynchus (Rhynchobothrius), and another is probably the same genus, or may possibly belong to Cyathocephalus ... .” Later on, however (p. 20), Herdman and Hornell reject the idea that the globular larvee may be Tylocephala or allied genera, and, in discussing the opinions of Giard and Seurat on the systematic position of Seurat’s larva, they say that they regard the terminal invagination, not as a sucker with a papilla on its floor, but as “the opening in a hood or depression formed by the sinking of the scolex into the front of its vesicle. The changes of shape which we observed in this larva in the living state, the protrusion and retraction of the papilla-like part which we regard as the anterior end of the scolex, agree with this interpretation. Consequently, we are of opinion that this larval Cestode is not one of the Monobothria—that it belongs to neither the Pseudophyllidea nor the Tetraphyllidea, but is a young Tetrarhynchid belonging to the Trypanorhyncha, and we give here (fig. 4) a series of diagrams in order to show the positions that we suppose our stages to occupy in the development oi,such a form.” Shipley and Hornell (Herdman’s Report IT. p. 80) call attention to the resemblance of ‘older examples of the larger larva (7'ylo- cephalum ludificans) to Seurat’s form, and think there is little doubt that they are at least generically the same (p. 82). Again, Southwell says (39, p. 169) : “Tt would certainly appear more probable as well as simpler, for this larva to develop into a Tylocephalum (as is believed by Seurat) than into a Tetrarhynchus.” Again, Southwell, speaking of the great scarcity of the adult of Tetrarhynchus unionifactor in Klasmobranchis taken by trawling, says (42 p. 130): ‘“‘ Tt would almost appear that this fact in itself is sufficient proof that the adult of the pearl-inducing worm is not Tetrarhynchus unionifactor.” But at the foot of the same page he reverts to the position that it isa Tetrarhynchus. THE CEYLON PEARL-OYSTER. 28] It is strange how the Tetrarhynchus unionifactor theory, once enunciated, has prevailed :—-indeed nobody seems to have seriously followed up the obvious clue given by Seurat’s discovery of the supposed adult of his worm. Prof. Herdman says in his Report, Part V. pp. 20-21: “Shipley and Hornell in Part IL. (p. 77) described and figured various stages of the Cestode larve both from the centre of decalcified pearls and also free in the tissues of the pearl-oyster, but left it an open question whether the sub- globular younger larvee [i. e. Z'ylocephalum ludificans, n. sp.| belong to the same life-history as the elongated older forms, which are young Tetrarhynchids. If our arrangement of the stages observed in the tissues of the pearl-oyster is correct, and if all these larve belong to the same species, then the interpretation we have given above brings us to the conclusion that the larger of our two globular larve belongs to the worm which Shipley and Hornell described as Tetrarhynchus unionifactor in 1904.” And, referring to some figures of 7'ylocephalum ludificans on pl. i. (Report, Part V. Pearl-Production) figs. 1-8, he says (p. 21): “there can scarcely be any doubt (1) that they all belong to the same life-history, and (2) that they are young Tetra- rhynchids leading on to the stages shown in figs. 10 and 11.” Prof. Herdman gives, in support of his theory, a series of figures showing the hypothetical transition from 7'ylocephalum ludificans to Tetrarhynchus unionifactor (Report, Part V. p. 21). Later, a younger Tetrarhynchus, 1 mm. in length, was found ia the stomach and alimentary canal of the o ster, which Shipley and Hornell (Report V. pp. 87-88) regarded as probably an earlier stage of Tetrarhynchus unionifacior, though possibly a distinct form. A single example of a still younger form, which is figured in the Report on Pearl-Production (V., pl. iii. fig. 10), and is described in the text (p. 22) as occurring “ encysted in the liver” and in the explanation of the plates as “ from cyst between stomach and liver,” appears to go still further towards linking the two forms. This larva is referred to in the text as °53 mm, long. T'ylocephalum ludificans grows to a much greater size than this without changing its characters; thus the one figured by Shipley and Hornell in the “Parasites of the Pearl-Oyster” (Report, Part IT. pl. i. fig. 12), and described as x40, appears from the size of the figure to be over 1:5 mm. long, and still shows no sign of becoming a TJ'etrarhynchus. And T. ludificans quite frequently measures 1 mm. in diameter. This discrepancy in dimensions makes it hard to believe that they are the same organism, and the gap between the 7Z'ylocephalum form, with its round Balanoglossus-like scolex or ‘ myzorhynchus,” and the 282 DR, H. LYSTER JAMESON ON Tetrarhynchus form, with its complex proboscides, cannot be said to have been satisfactorily bridged. Herdman found the Tetrarhynchus form much scarcer than ae E ylocephalum form, and it appears from his Report, Part V. p. 22, that the ratio of the latter to the former is about 200: 6. Shipley and Hornell (Report, Part II. p. 79) give the ratio of globular larve to undoubted Tetrarhynchi as 100: 1. Prof. Herdman’s suggested explanation of this, namely, that the globular parasite only occasionally advances to the Tetrarhynchus stage, requires, it seems to me, a greater effort of the imagination than the hypothesis that the two worms are distinct forms. It is hard to conceive of conditions that would lead a small minority of Zylocephalum ludificans or 7’. minus to leave their tough fibrous cysts in the peripheral tissues, and migrate to the sities dine, there to take on the Vetrar Hneios form. It seems to me much easier to regard these as two (or three) distinct species, and their simultaneous presence in one host as a case of parallel infection. In his latest paper (42, p. 129), Southwell, speaking of these undoubted Tetrarhynchids, says :— “These are by no means rare, and are in almost every case confined to a particular part of the wail of the gut, about one inch from the anus and on the terminal part of the gut. They often occur in clusters of three or four. They are small (about 1 mm.), but appear to be adult in every way, save that strobilization has not commenced. This encysted young ‘Tetrarhynchid is quite dissimilar to the globular cysts found in the same oyster. In the latter case, the larvee are so young that the Cestodian characters are te ill defined. Tn the ronnen case, a normal and full-grown Tetrarhynchid head is present. No stage or stages have been found inter- mediate between them, and the evidence that they are both stages in the life- history of the same parasite rests on cireum- stantial evidence and on evidence obtained by feeding experiments.” And with reference to these feeding experiments, which are referred to below (p. 287), and in which Zetrarhynchi were found in Sharks that had been fed on pearl-oysters, Mr. Southwell says (Ga, XO) e— ‘““The mere fact that the adults were obtained by feeding is in itself almost sufficient to prove that they are the adult of the pearl-inducing worm, for it is difficult to believe that their occurrence in the (Ginglymostoma was a mere coincidence each year.” I think there is very good reason to believe that Southwell did, in his feeding experiments, actually transmit Tetrarhynchus unionifactor from. the Oyster to the ‘Elasmobranch, but it is THE CEYLON PEARL-OYSTER. 283 difficult to escape the conclusion that the worms found in Gingly- mostoma were derived from the Vetrarhynchus larve in or around the alimentary canal of the Oysters, and not from the globular Tylocephala in the other tissues, to which Southwell refers when he speaks of the “ pearl-inducing worm.” ‘To dispute this view, it would be necessary to demonstrate that the Zetrarhynchus-stage was not present in the Oysters used. Shipley remained throughout sceptical about the identity of the supposed pearl-forming larvee with Zetrarhynchus unionifactor. In Part II. of Herdman’s Report, p. 86, he says it is most improbable that the young larve grow into the Zetrarhynchus larva. In their report on the Cestode and Nematode Parasites from the Marine Fishes of Ceylon, Shipley and Hornell say (Pt. V. p. 66) :— “It seems increasingly probable that the pearl-forming Cestode is a 7. unionifactor, but this has not yet been proved.” Shipley and Hornell, in Herdman’s Report, Part V. p. 98, offer the following hypothetical life-history :— “Of the given number of larvae which enter at a very early stage into the body of the Oyster a certain number arrive in the mantle and other tissues, acquire an ectodermal sac and there encyst, and find a costly grave in the developing pearl.” [The ectodermal sac around these parasites is so far purely hypothetical and has never been demonstrated.—H. L. J.] “The remainder, however, reach the alimentary canal and grow and flourish there. When they attain the dimensions of thestages described in Part IT. they leave the alimentary canal and encyst, usually upon the outer surface of the intestine. Now they are too big for enclosure in a pearl, and they can wait without anxiety for the advent of their second host (Khinoptera javanica), within whose intestine they rapidly become sexually mature.” It would seem to the present writer much simpler to set aside, for a while, the hypothesis that Tylocephalum ludificans and 7’. minus are younger stages of a Tetrarhynchus, and to seek for their adult stages among the members of the genus Tylocephalum, or allied types described as new genera, occurring in oyster-eating Elasmobranchs. Shipley and Hornell have already described a number of these, which I give below :— *tTylocephalum (Tetragonocephalum) trygonis (Report, Part III. p. 51 and Part V. pp. 48 & 83). Habitat: intestine of Trygon walga and Aétobatis narinari. Diameter of head 0-03 mm. *Tylocephalum (Tetragonocephalum) aétobatidis (Report, Part III. p. 52 and Part V. p. 48). Intestine of a Possibly the smaller Tetrarhynchus found in the intestine of the Pearl-Oyster, if it is distinct from 7’. wnio- nifactor. / y / Li?) } DrAGram illustrating my hypothesis of the relations of the several forms and stages of Cestode larye described in Herdman’s Report. (The letters correspond to those in the above diagrams. Those marked A’, A’, B’, and J’ are regarded as parallel stages to A, B, and J.) Species I. Tetrarhynchus unionifactor. A D Larval 9 Vetrarhyn- Egg, (2) swallowed by yee i chus unionifactor, in Pearl-Oyster ; hatch- : ree : RT and around the ali- P 2 Ing out in intestine to mentary canal of the become \ Pearl-Oyster. \ \ \ x ¥ Adult Tetrarhynchus unionifactor in ali- mentary canal of Rhi- noptera javaniea and Ginglymostoma con- color. Species LI. Z'ylocephalium ludificans. B (?) Hornell’s free- swimming J\arva. Pd ati A! "sf ake CG MESO? 2 SS Maa Egg, (?) hatching in Globular cysts, Tylo- sea-water to become B , cephalum tudificans, or (?) swallowed ~by-————_—>-— in liver and connective Pearl-Oyster to be- , tissues of the Pearl- come C. \ Oyster, x ¥ J An adult Tyloce- phalum-like form in one of the oyster-eat- ing Elasmobranchs, probably — Aétobatis narinari. Proc. Zoou, Soc,—1912, No. XIX. 19 Dye 290 DR. H. LYSTHR JAMESON ON Ql = . Species IIT. Zylocephalwm minus. B’ (?) A free-swimming larva, hke B above, only smaller. N A’ i Egg, (?) hatching in , The smaller globular 5 _ / cyst, Lylocephalum sea-water to become b, Ta a minus, mM connective or (2) swallowed by tissues of the Pearl- oyster to become G. ‘ Oyster. X ¥ af An adult Tyloce- phalum-like form, in one ot the oyster-eat- ing Klasmobranchs. Scolex probably about ‘2 mim. in diameter. (5) Description OF THE TWO GLOBULAR CEsToDE LaRVa FROM tHE CEYLON PEARL-OysTER. I append the following descriptions. They are certainly incomplete, being based on examination of preserved material and on the descriptions of previous writers :— Tylocephalum ludificans, sp.n. (The larger globular larva ; the supposed pearl-producing worm.) (Pl. XLVI. figs. 98 (type) & 59.) The type, fig. 58, is in Slide 94 in Prof. Herdman’s Collection. Tetrarhynchus unionifactor (young) Herdman. (For other figures see Herdman’s Report, Part II. Parasites of the Pearl-Oyster, pl. i. figs. 12 & 13; Part V. Pearl-Production, pl. u. figs. 11, 12, & 176, pl. iii. figs. 1-5, 6, 7, 8, & 9; also Part V. p. 21.) Globular Cestode larvee, with rostrum or myzorhynchus (Linton) retractile within a denticulated collar. Form more elongated when liberated from capsule; length 0°5 to 1-5 mm, Average diameter of seven specimens sectioned on Prof. Herdman’s slides and examined by the writer, 0°78 mm. THE CEYLON PEARL-OYSTER. 291 Myzorhynchus uniformly muscular, without obvious division into muscular tracts; retractile within an annular collar; in section it may appear either conical, lenticular, or flattened, concave and sucker-like ; protrudes as a conical papilla when in locomotion, This anterior muscular region, including the collar, is about one-third of the total length of the larva when extended. The whole myzorhynchus can be protruded, the collar then forming an annulus around it. Collar or cephalic sheath muscular with denticulated cuticle, the denticles tricuspid. (Herdman’s Report, Part II. (Shipley & Hornell, Parasites of the Pearl-Oyster) pl. i. figs. 10, 11, & 14, pl. ii. fig. 18; also Pt. V. (Pearl- Production) pl. iii. fig. 9.) The denticles measure from 3 p to 5 u in diameter. Hinder part of the larva centrally parenchymatous, the parenchyma containing the calcareous corpuscles characteristic of Cestode larvee, peripherally more muscular. The hinder part of the body is covered by a thick, radially marked epicuticle, permeated by numerous closely-set tubuli, and suggesting on superficial examination a coat of cilia. This epicuticle varies in thickness but is generally about 0:03 mm. thick, and the true cuticle lies under it. This form is distinguished from the next described worm by its larger size (Herdman gives the size as about six times that of the smaller form), the undivided musculature of the myzorhynchus, and the wider and more open character of the collar-sheath of the myzorhynchus in the resting-stage. Habit. Resting in spherical fibrous cysts, derived from the connective tissue of the host, in the Ceylon Pearl-Oyster, Margaritifera vulgaris. Most frequent in the visceral mass, notably the liver. Habitat. Gulf of Manaar (Herdman & Hornell). Trincomalee ( Willey). The following is a description of a worm which I regard as in all probability the adult of this larva. The single specimen was obtained from the spiral intestine of Aétobatis narinari, by Mr. Hornell, on 4th January 1905, and had apparently been overlooked by Mr. Shipley among some duplicate specimens of Kystocephalus translucens, along with which I found it when examining Dr. Shipley’s material. After it had been cleared and examined as a transparent object, Dr. Shipley very kindly allowed me to have sections cut from it to compare with those of the larva in the pearl-oyster. (2) Adult of Z'ylocephalum ludificans, sp.n. (Pls. XLVI. & XLVII. figs. 60-64.) Length 12mm. Head 0:6 mm. long by 0°5 mm. broad ; pyriform, slightly broader in front than behind ; transition from head to neck not very sharply defined. The myzorhynchus in this specimen is retracted within its sheath, as is usually the case with the larva in the pearl-oyster; it is about ‘3 mm. in diameter. Around the head are four marginal suckers about ‘125 mm. in diameter. Proglottides about 140 in number, increasing but little in breadth from before backwards; they 19* 292 DR. WH. LYSTER JAMESON ON begin to increase notably in length from about the 85th back- wards. The largest hindmost segments are about *5 mm. long, and slightly longer than broad (fig. 64). The armature of the collar @ (in figs. 61-63) is similar to that of the larva. In section (fig. 62) the myzorhynchus is seen to be retracted in such a way that its anterior surface is thrown into folds, thus resembling the condition of the larva shown in fig. 59. The only point in which the head of this worm appears to differ from the larva in the pearl-oyster is im the presence of the four marginal suckers, which may well be a feature first acquired in the final host. Tylocephalum minus, sp. n. (Plate XXXIIT. fig. 2.) (The smaller globular larva, which Prof. Herdman thinks may also be concerned in pearl-formation.) (Tetrarhynchus sp., Herdman.) For other figures see Herdman’s Report (Pearl Production), Part V. pl. ii. figs. 1-3, 174, 18-22; also text-figure 3, p. 19. Diameter of resting parasite in cyst from 0-07 to 0-2 mm. Average diameter of 40 examples shown on Prof. Herdman’s slides and measured by the present writer, 0-14 mm. Body sub- globular, consisting, as in 7’. ludificans, of an anterior muscular and a posterior parenchymatous part, the anterior muscular portion (myzorhynchus) consisting of a conical papilla in a ecup- or flask-shaped depression formed by the surrounding muscular collar or sheath. Asa rule, in preserved specimens, the opening of this depression seems relatively narrower, and the papilla more conical and less flattened than in the previous species. The musculature of the myzorhynchus shows, in some examples, a tendency to break up into four longitudinal tracts. In young examples the myzorhynchus may be barely differentiated. Cuticular spines are present on the collar, but they are smaller and relatively finer than in 7’. ludificans. The epicuticle is about ‘Ol mm. thick. This form is distinguished from 7" ludificans by its smaller size and finer armature of the collar, and by the tendency of the myzorhynebus musculature to break up into four strands. It is regarded by Southwell as the same species as 7’. ludificans. Habit. Resting in spherical fibrous cysts in the connective tissues of Margaritifera vulgaris, occurring in the visceral mass, mantle, gills, ete. Habitat. Gulf of Manaar. Prof. Herdman, while he regards the form here named T. ludificans as the pearl-producer ‘par excellence, considers that the present species too ‘‘may occasionally form the nuclei of pearls” (Report V. p. 22). Particulars of the structure of both these forms are given on pp. 79-82 of Part II. of Prof. Herdman’s Report. THE CEYLON PEARL-OYSTER. 29 (6) Oxservations oN tHE SrRucTURE oF THE FrBrous Cysts SURROUNDING THE CrsToDE LArvV® IN J/4RIGARTIFERA VULGARIS. T may here add a few notes on the structure of the investing eysts of Tylocephalum ludificans and 7’. ninus, based upon my examination of Professor Herdman’s slides and Dr. Kelaart’s material, In the earliest stages the cyst may be scarcely differentiated from the surrounding tissue, and about 0°01 or 0-02 mm. thick. This condition I find specially associated with a little-developed phase of the smaller larva 7’. minus, measuring 0:08 mm. in diameter, and resembling B in figure 4 on p. 21 of Part V. of Herdman’s Report. In such thin cysts the nuclei of the fibres are distinct, though hardly more so than those of the general connective tissue of the oyster. One or two examples at this and later stages were found in the muscular tissue without any surrounding cysts at all, beyond a little of the interstitial tissue of the muscle-bundles (PI. XXXIIT. fig. 2). As the fibrous capsule becomes thicker the nuclei appear at first to become more abundant, and this may well be associated with the growth and multiplication of the fibres. As a rule, the thicker cysts (0-2 mm. thick and over) seem to be less densely nucleated, and may even show very few nuclei, especially when they become highly areolar and oedematous. The outer part of the cyst is usually ordinary areolar connective tissue, with branched and anastomosing fibres passing over, often quite imperceptibly, into the general con- nective tissue of the body, such as occurs between the tubules of the liver. The cyst is, however, typically lined with several layers of more regular parallel fibres, with abundant nuclei. In some cases the fibres seem to coalesce to form a dense almost gristly substance, without obvious nuclei. The nuclei of the fibres are long and narrow, and are situated on their outside edges. In some cases the cyst appears to be entirely without nuclei, and in such cases the fibres are often very thick, measuring as much as 10 or 15 yx in diameter. There is never, so far as I can see, any trace of a lining epithelium, though the cyst may be lined with a layer of granules, possibly derived from the Cestode or from the leucoey tes of the blood. In certain cases large dark-staining bodies were seen in the aveole of the fibrous connective tissue of the cyst, which suggested parasitic Sporozoa, but the preparations did not allow of detailed examination. A typical section of the cyst of the smaller parasite, Tylocephalum minus, is shown on Pl. XX XIII. fig. 3. This condition of things is very different to that which is found in the case of the pearl- inducing Trematode of Mytilus described in my paper (25). Here the parasite is surrounded by an 294 DR. H. LYSTER JAMESON ON epidermal sac (d. ¢. pl. xv. fig. 5) of the same nature as the outer shell-secreting epidermis. In such a case it is easy to understand how the parasite, when it dies, hecomes encased in a pearl, laid down, layer upon layer, by this epithelium *. (7) MATERIALS AVAILABLE FOR THE PRESENT INVESTIGATIONS. I have throughout these investigations been seriously handi- capped by the extreme difficulty of obtaining material. Many of the points which remain obscure could probably be cleared up if I could obtain properly preserved specimens of pearl-bearing oysters from the Gulf of Manaar. Unfortunately, I have been quite unable to obtain these. I endeavoured to do so through the Ceylon Company of Pearl Fishers, Ltd., and Mr. Southwell, but without success, Mr. South- well replying that there were no oysters on the banks and that his own preserved material was finished. The Company, however, kindly forwarded to me a suggestion made by Mr. Southwell to the following effect :— “As it is probable Dr. Jameson requires Ceylon pearls (with the particular parasite giving rise to same), I would suggest that in order to ensure that the pearls are from Ceylon that they be bought here. I shall be glad to pur- chase pearls for Dr. Jameson, if he will give me some idea what to get and how much to spend.” I gladly availed myself of this offer, and asked Mr. Southwell to spend five pounds in the purchase of ‘“‘cyst-pearls.” For this sum he procured from a local jeweller a parcel of 21 small “ fine” pearls, which I received in February 1911. * I must here incidentally refer to a quite erroneous interpretation which was placed upon the expression of my views as to the origin of the sac in Mytilus in my paper above referred to. My account of the development of this sac on p. 149 appears to have been taken by Herdman and by Boutan (3 & 4) to imply that I thought the sac arose from the mesoblastic connective-tissue elements of the mantle. As I explained in a letter to Prof. Herdman, which he was good enough to publish, as showing my views, on p. 9 of Part V. of his Report, I never had any doubt that the sac was a true epidermis. What I wished in my paper to emphasize was that mm Mytilus it appeared to arise independently of, and not in continuity with, the outer epidermal epithelium, perhaps from in-wandering epidermal cells, perhaps from more deeply seated elements of epiblastic origin, some of which (e.g. certain flask-shaped glands in Margaritifera, see P|. XI. fig. 33) appear to project below the basement-membrane. Had I dreamed that I should have been suspected of attempting to promulgate heretical views on the doctrine of the immutability of the three primary germinal layers, I would have been more cautious in the choice of my phrases. But even if my wording in that paper was unintentionally somewhat ambiguous, my 7éswmé of my work in ‘ Nature’ (26) should have cleared away any misconception, for in that paper I definitely stated (p. 280) that “a true pearl is laid down in a closed sac of the shell-secreting epithelium, embedded in the subepidermal tissue of the mantle and completely cut off from the outer epithelium itself... .. Such a sac, with its contained pearl, may be compared to a human atheroma cyst.” I have not yet reached the stage at which I can add to what I said in 1902 about the actual mode of origin of the epidermal sac in Mytilus, but I hope before long to be able to contribute some more facts on the subject. THE CEYLON PEARL-OYSTER. 295 I then tried the Colombo Museum in the hope of getting some oysters with pearls in situ, but Dr. Pearson had no preserved material to spare. I tried to obtain material from Madras from Mr. Hornell, but he wrote me, in January 1911, that his own material was exhausted, and that he would not be able to obtain any more till the next inspection, a year later. However, H.H. the Jam Saheb of Nawanagar most kindly sent me some preserved specimens of this species with pearls in situ from the Gulf of Kutch, and I hope, in a later publication, to be able to put forward some observations on the actual process of pearl- production, based on these. The following material was available for these investiga- tions :— (i.) Twenty-one pearls bought in Ceylon. It is, of course, possible, though not probable, that some of these originally came from elsewhere, e.g. the Persian Gulf wid Bombay, but they, or at least the great majority of them, were certainly derived from MW. vulgaris, the pearls of which have a characteristic colour and lustre quite different from that of the pearls found in M. margaritifera and M. maxima. They were small “ fine pearls,” mostly spherical, a few oval or slightly lenticular. One wasa brown pearl formed in the mantle- margin from the prismatic substance. They were all decalcitied and examined whole, cleared in oil of cloves, and drawn. They were then sectioned (except in the case of three examples which were preserved whole). Their nuclei were in no cases Cestodes ; they usually contained a cavity with a few granules surrounded by spheevocrystal-like matter, allied to or identical with the “ repair-substances ” described below. In several cases, however, the actual nucleus was a grain of sand. These specimens are preserved as preparations XL, XLII, XLIII, XLIV, XLV, Oe Vb, at VEEL, Jal DV Any,.A. LEV. By V dL Vp, iN ey, ives ULI a, Lives, Livery, LEV s, and) LEV « (Pls. XLI.-XLITI. figs. 35-45 and Pls. XLV., XLVI. figs. 50-57). (ii.) Dr. Kelaart’s Material in the British Museum. In 1901, when JI was investigating the origin of pearls in Mytilus, Mr. EK. A. Smith, I.8.0., allowed me to examine five old specimens of the Ceylon Pearl-Oyster from Dr. Kelaart’s collections in the British Museum. Mr. Smith very kindly allowed me to make further use of some of this material for the present investigations. The specimens are labelled :— “] specimen of pearls in ovaria, 3 specimens of pearls in mantle, 1 specimen of ova of Entozoa in liver of Meleagrina margaritifera.” The specimen with ‘‘ pearls in ovaria” was a pearl-oyster with 296 DR. H. LYSTER JAMESON ON a quantity of clustered pearls, mostly of the baroque and seed- pearl classes, in the visceral mass. The three examples with ‘“‘pearls in mantle” showed pearls, chiefly in the regions of the levator muscles, though some were in the non-muscular parts of the visceral body-wall. The specimen with ‘ ova of Entozoa in liver” is interesting, as showing the Cestode, Tylocephalum ludificans, in 1ts whitish fibrous pearl-like cysts, which on super- ficial examination suggest “eggs.” It was in this specimen, in 1901, prior to Prof. Herdman’s departure for Ceylony that I first became acquainted with these larve, which Prof. Herdman identified as the cause of cyst-pearls. The few observations that I was able to make at that time led me to the conclusion that there was no evidence that this parasite was concerned in pearl- formation *, a conclusion that I have, so far, seen no sufticient cause for modifying. Owing to their age, the state of preservation of these specimens was naturally somewhat defective, and for real detailed histological work upon the pearl-producing tissues they were quite useless. Many of the pearls in these specimens had fallen out of their sacs and lay in the bottom of the jar. Some of these, along with others picked out of the tissue, numbering 22 in all, were decalcified and examined in oil of cloves, and six of them were then sectioned and further examined. [Preparations XIV, XV, EXCV Ly XOXGT co, XOX G, XGXeT (GR IS.Y XOXO VAIS SXOXONG Vane figs. 16-18 and Pl. XLIV. figs. 46—48).] A large piece of tissue in the wall of the visceral mass, measuring about 5x5x4 mm., and containing no less than 16 pearls, was cut out from the specimen with “ pearls in ovary,” decalcified, stained with borax carmine and indigo carmine, and sectioned [Preparation XXVIII (Pl. XXXVII. figs. 14, 15)]. These pearls were all of the class which I refer to provisionally (see below) as muscle-pearls, and were mostly formed around central cavities. (111.) Onlabelled Material in the British Museum. Mr. Smith also allowed me to examine two unlabelled speci- mens of Margaritifera vulgaris in the British Museum, the history of which is unknown. One of them was with the example in spirit now on show in the Museum, and was accompanied by its shell. It is from this example that preparations XX VII and XXIX were cut. It contained a large number of muscle-pearls and what Prof. Herdman calls ‘“caleospherules” in the left mantle-lobe, and in the region of the adductor muscle on the left side. The other example had been removed from its shell. It contained a large number of clustered pearls, of all sizes, in the right mantle-lobe. The tubes in which the specimens were preserved contained also a lot of loose pearls which had dropped out of both these specimens. * Tn 1902 (25), p. 149, I poimted out that Cestode larvee were not surrounded by a pearl-sac. THE CEYLON PEARL-OYSTER. 297 From the first of these specimens the following preparations were made :— a) Preparation XX VII, a piece of tissue cut from the border- land between the mantle and the adductor in the first of the above specimens. This piece measured about 7x5x4mm., and contained 36 small pearlsand numerous so-called “ealeospherules.” The preservation was so bad that no differential staining of the soft tissues could be obtained, all parts reacted alike to the stains used, [Preparation XXVII (Pls. XXXVIII., XXXIX. figs. 19-21, Pl. XL. figs. 24—27.)| (b) Preparation XXIX was a piece of the mantle of the same individual near the margin, containing 17 so-called ‘‘ caleospherules,” one of which is becoming coated over with nacre (Pl. XX XIX. figs. 22 & 23). The figures were made from the whole object— tig. 22 representing it as it was before decalcification, fig. 23 after it had been decalcified ; both as seen when cleared with oil of cloves. The preparation was then sectioned, but the state of pre- servation did not allow of the relations of the “ calcospherules ” to the tisstes being investigated in this instance. A piece of tissue was also cut from the second of these specimens, decalcified, examined entire, and sectioned. It contained about 20 small earls and numerous so-called “ calcospherules.” [Preparation XXIV .| Forty pearls, of varying sizes, some lying loose in the bottoms of the jars containing the specimens, others taken from the tissues, were decalcified and examined in oil of cloves. Of these, six were sectioned and further examined. [Preparations XXIII, LXTII (A, B, & L), and LXVI (4&1) (Pls. XXXIX—-XLI. & XLIV. figs. 21 a, 28, 31, 32, 49).] All the pearls from these specimens I refer to the class called by Herdman “ Muscle-Pearls.” (iv.) Three Specimens of the Pearl-Oyster collected by Professor Herdman in 1902. Prof. Herdman, at the request of the Ceylon Company of Pearl Fishers, Ltd., very kindly allowed me to examine his material (see (v.) below) and handed me three specimens of the Pearl-Oyster, each of which contained a small “ muscle-pearl” at the point of insertion of one of the levators of the foot. The pieces of tissue containing these three pearls were cut out, decalcitied, and sectioned [ Preparations IV, VI, and VII (Pl. XXXYV. fig. 8)}. Although these specimens had, apparently, been preserved in formalin, which is not the most satisfactory preservative for histological purposes, they showed quite a lot of histological detail, and enabled me to form some idea of the mode of origin of muscle-pearls, and of the curious cyst-like bodies which precede them. (v.) Professor Herdman’s Slides. As stated above, Prof. Herdman very kindly allowed me to examine his slides, which he sent to me a few at a time. 298 DR. H. LYSTER JAMESON ON Most of these slides were preparations showing the parasitic Cestodes in the tissues of the oyster, but there were also a number of preparations of pearls, sectioned im situ in the tissues, showing in all about 25 pearls, 21 of which showed their nuclei more or less distinctly. The nuclei of these pearls were of very different characters, but in no case could I identify a Cestode larva in the centre of a pearl. (vi.) Three Specimens from the Persian Gulf. In September 1903, Mr. J. Calcott Gaskin, Assistant Political Agent at Bahrein, Persian Gulf, sent me 32 specimens of Margaritifera vulgaris from Bahrein preserved in alcohol. Out of 20 of these that I opened, 3 contained pearls, which, from their position, could obviously be classified as ‘‘ cyst-pearls ” (Herdman). Two contained a single pearl each, that in the first beg about 2°5 mm. in diameter, situate in the left mantle-lobe, above the anterior end of the attachment of the gills [ Preparation LXIV 4], that in the second {Preparation LXIV B] being about 1 mm. in diameter and situate in the body-wall over the stomach. The third specimen had two small pearls, about 2 mm. apart, in the wall of the visceral mass, away from all muscle-impressions |LXIVc}. All these pearls were decalcified in situ in the tissues and sectioned. Their centres are described below. In addition to the above the following pearls were decalcified and examined. More detailed particulars are given under the descriptions of the centres of individual pearls, given below :— (vu.) Dry unlabelled pearls, probably from Ceylon, in the British Museum, three examples were decalcified. (viii.) Mixed lot of pearls; given to me by Mr. Max Mayer, mostly from Margaritifera vulgaris ; 115 were decalcified, of these 8 were sectioned. (ix.) A collection of pearls from the last Ceylon pearl fishery, given to me by Mr. EH. Hopkins. Fifteen were decalcified, and four of these were sectioned. x.) A collection of pearl-oysters, with pearls im setw, from the Gulf of Kutch; these are referred to above. Up to the time of writing, 18 pearls from these specimens have been decalcified, and 13 of them sectioned. (xi.) Two pearls from Margaritifera vulgaris, from the Mediterranean, given to me by Professor Raphael Dubois. (xii.) Five pearls from Margaritifera vulgaris, from New Caledonia, given to me by Professor L. G. Seurat. (xii.) A pearl from Margaritifera vulg Sr, from Madagascar, gtven to me by Professor Seurat. (xiv.) Two pearls from Margaritifera vulgaris, from Papua, from the Imperial Institute. THE CEYLON PEARL-OYSTER. 299 (xv.) Twenty pearls from Placuna placenta, from Lake Tam- palakamam, Ceylon, from the Imperial Institute. (xvi.) About a dozen pearls from Murgaritifera margaritifera var. cumingii, from the Gambier Archipelago. In the course of these observations, apart from studies on the structure and formation of pearls in other forms, 356 pearls derived, with perhaps a few exceptions, from Margaritifera vulgaris, chiefly from Ceylon, have been decalcified and examined, 175 of these having been studied in sections. (8) Mernops. For decalcification, whether the pearls were free or in situ, preserved in alcohol or dry, I found alcohol of about 50 per cent. strength, to which a few drops of nitric acid had been added, was the best. Of course, a preserved pearl never decalcifies as well as a fresh one. In the case of dry pearls, where only the nucleus and central parts are required for examination, it is often an advantage, during decalcification, to strip off the outer layers of conchyolin, thus facilitating the penetration of the reagent. Bubbles of carbon dioxide, generated in the process of decalci- fication between the conchyolin-layers, cause a great deal of trouble, especially in old dry pearls, where the conchyolin seems to be particularly leathery and impermeable. Such bubbles often greatly distort the normal structure of the pearl, as seen in section, by tearing the conchyolin-layers apart and causing great spaces betweenthem. ‘The most suitablereagent for expelling the bubbles is absolute alcohol, in which the decalcified pearl is placed for a few days. In some cases, however, it was necessary to extract the gas under an air-pump. For staining decalcified pearls hematoxylin was used, also borax carmine. Sections of the pearls in the tissues were stained sometimes with borax carmine and picro-indigo-carmine*, sometimes with hematoxylin and eosin or orange, occasionally with other reagents. (9) SrRUCTURE OF THE SHELL-SuBSTANCES. The shell of Margaritifera consists of the following parts :— (i.) the outermost layer or so-called Periostracum ; (ii.) the prismatic layer, forming with (1) the ‘“ back” of the shell, the fragile, dark-coloured “lip,” and the lappet- like processes of the margin ; * Borax carmine (Grenacher’s) in bulk :— Picro-indigo-carmine as under, on the slide. A. Saturated solution of picric acid in 90 per cent. alcohol. b. Saturated solution of indigo-carmine (Grubler) in 70 per cent. alcohol. 1 part of A, 2 parts of 5, 6 parts of 70 per cent. alcohol. 300 DR. H. LYSTER JAMESON ON (iu.) the Nacre or Mother-of-Pearl, forming the lining and the bulk of the shell ; (iv.) the Hypostracum, the substance to which the muscles are attached by a specialised epithelium ; (v.) the Hinge Ligament. The mass of the shell is further divisible chemically and microscopically into an albuminoid substance called ‘ conchyolin ” and erystallme carbonate of lime deposited therein. Romer’s careful observations (32) have shown beyond a doubt that there is a sharp separation between these two substances: the conchyolin forming an alveolar framework, in the chambers of which the salts are deposited ; the structure of the calcium carbonate being crystalline, its form being determined by that of the spaces in which it is deposited. The ratio of conchyolin to calcareous salts differs in different parts of the shell. Thus Rémer (32) has found in Margaritana, the fresh-water pearl-mussel, that the organic substance con- stitutes 1:47 per cent. by weight of the prismatic substance, but only *64 per cent. of the nacre. This 1s most interesting as giving support to the theory of the present writer, enunciated below, that the different structures of the different forms of shell-building substances, normal and pathological, are in part a function of the proportions in which these two constituents are secreted by the tissues of the mollusc. To turn now to the details of the structure of the several constituents of the shell. (1.) The Periostracum. The origin of the Pertostracum can best be understood if we consider first those forms which live in fresh or estuarine water, or are otherwise subjected to conditions which render necessary a thick cuticle-like layer to defend them from the erosive action of organic acids derived from decomposing animal and vegetable ranentor (e.g. the Unionide and J/ytilus). The periostracum in such cases has been described fully by several authors, e.g. Biedermann (1), Moynier de Villepoix (28), Tullberg (47), Khrenbaum (9), Felix Muller (29), Stempell (44), List (27 5), etc. In these cases the periostracum 1s composed of two constituents. The outermost layer is probably formed as a true cuticle directly by transformation or cuticularisation of the outer surfaces of the cells of a specialised epithelium in the inner (axial) face of a deep groove which runs along the mantle-margin, and which has been called by Moynier de Villepoix (28, p. 18) the ‘“‘fente marginale.” This mar ginal eroove divides the mantle-margin into an inner and an outer lobe, the former being piemented and sensory, the latter being a part of the shell- -secreting apparatus. This outer THE CEYLON PEARL-OYSTER, 301 layer of the periostracum is closely adherent to the specialised epithelium, so that secondary thickening, if it takes place (and my own observations on Mytilus and Modiola lead me to think that it does so to some extent, a view which is held also by List, 27 6, p. 55), differs from that of all other parts of the shell (including the inner layers of the periostracum) in that it is secreted from outside or centrifugally with respect to the body of the animal and the shell, instead of from imside or centripetally. It would, indeed, seem as though there were morphological grounds for restricting the name periostracum to this particular lay er of the outer cuticle-like substance, or, failing that, for introducing a term which would separate it more shar ply from the more bulky inner layers. The structural distinctions of this layer are well shown by Romer (32) fig. 25 ( Margaritana), by Moynier (28) fig. 50 (Mytilus), by Tullberg (47) Taf. iv. fig. 3, fig. 4d (Mytilus), and by List (27 6) in the “My tilidee generally. The greater part of the mi hes rs however, 1s laid down centripetally, layer upon layer, by the epithelium on the outer side of the marginal groove (7.¢e. on the inner side of the outer of the two lobes-of the mantle-mar ein, Tullberg (47) p. 27). It is stratified, and in Mytilus contains, near its outer limit, a charac- teristic layer of largealveol. The stratifications of this substance have been shown by Romer to correspond to layers of minute alveoli (32, fig. 25). Internally the inner layers of the periostracum pass over into the conchyolin framework of the prismatic layer. In some forms, e. g. Anodonta, the distinction between the two constituents of the periostracum are emphasized by the outer layer being much greater in area than the inner ones, and being thrown into folds upon which the ner layers le unconformably. The Mother-of-Pearl Oysters (together with such forms as Ostrea and Pecten) differ from the types to which the above description refers in the fineness of the periostracum and in having much more freely retractile mantle-margins. In sections of the decalcified shells of the Mother-of-Pearl Oysters it is diftieult— indeed, I might say impossible—to differentiate the periostracum from the outer layer of the organic basis of the prismatic sub- stance (text-fig. 35, p. 302; see also Pl. XXXIV. fig. 6) ew Hiéne marginal gr owth proceeds by a series of steps and retreats, the free mantle-margin being retractile to the edge of the nacre, and being so retracted when the shell closes. ie after a nee process of the lip has been formed, the mantle-margin is withdrawn, and forms a fresh attachment on the inner surface of the last- formed lip, from whicha fresh lip is produced. So the periostracum of lip no. 2 is attached to and apparently a direct continuation of the inner surface of the conchyolin of the prismatic layer of lip no. 1, and constitutes the outer layer of the conchyolin of the prismatic layer of lip no, 2. But Herdman has shown that, difficult as it is to distinguish a separate periostracum in sections of the shell, such a layer, of extreme delicacy, does exist at the 302 DR. H. LYSTER JAMESON ON margin, and arises in the normal manner in a marginal groove ae Report, Part II. Anatomy of Pearl- Oyster, plate vill. fig. Text-fig. 35. eTTTTATTT mu i ial oe i ee iii iii Margaritifera vulgaris, Persian Gulf. Section through the lip of the shell, after decalcification, showing the successive lappet- like processes of the prismatic substance (J., 7.’, 1.’”, 1. my pr., prismatic substance ; Sér., stratification of same. A, A’, A", AM points marking the successive retreats of the secreting margin, which takes place when new lappets are to be formed. At these points the ** periostracum ” of the new lappet is continuous with, and indistinguishable from, the inner conchyolin-layer of the prismatic substance of the last-formed lappet. Preparation X (X 35), see also Pl. XXXIV. fig. 6 (ii.) The Prismatic Substance. Reduced to its simplest terms the prismatic layer of the Mother-of-Pearl shell consists of prisms of calcium carbonate perpendicular to the surface of the shell, bounded externally and internally by membranes of conchyolin, which are connected by vertical membranes forming the septa between the prisms (text-figs. 35 and 36; see also Pl. XXXIV. figs. 6,6a; Pl. XL. fig. 29a). Where interruptions in the continuity of the growth of this layer have occurred, the layer of prisms may be divided by one or more horizontal sills of conchy olin (text-figs. 35, sér., and 38, str.), which break up the prisms into seoments, or which divide the layer into two or more series of prisms. The individual ends of the prisms in one layer do not of necessity coincide with those of the prisms in the next layer, though they frequently do coincide. The septa between the prisms may also show annular thickenings, corresponding to zones of constriction around the prisms (Pl. XXXIV. fig. 6 a, ann.). Romer has shown (82, p. 35) that the prisms of the pearl-shell (like those of Pinna, described by Biedermann (1), p. 9) behave between crossed nicols in the same manner as single crystals. The prisms differ enormously in size, according to the age of the oyster and the conditions under which they are secreted. There is a sharp line of demarcation between the prismatic and the nacreous layers in Vargaritifera, the innermost layer of the conchyolin of the former being connected to the outermost layer of that of the latter by a series of fine connectives of conchyolin (Pl. XXXIV. fig. 6 a, con.), forming a curious alveolar layer. THE CEYLON PEARL-OYSTER. 3038 The prismatic substance is secreted by that part of the epidermis apposed to the inner surface of the shell which is nearest to the margin of the mantle, and it is clear from the rapidity with which the columnar lip and its lappet-like processes are re- generated when injured and are added to in growing young shells that the characters of this layer are associated with relatively rapid secretion. This is significant, in view of the resemblance of this layer to some of the rapidly secreted repair-substances which replace the nacre under certain abnormal conditions (see below). Roémer’s work (p. 18) gives an interpretation of the nature of the prisms, which 1 have found most useful in helping me to interpret my own observations on pearl-formation. According to this hypothesis, which was suggested to Romer by my illustrious teacher, Prof. Biitschli, each prism is an incomplete spherocrystal, the growth of which has been arrested in all directions but one, viz. the direction from which the new shell-substance is secreted. Romer says (p. 18) :— “Dass diese Spharokristalle der einzelnen Prismen so unvollstiindig ausgebildet sind, rithrt daher, dass gleichzeitig und dicht nebeneinander die Anfinge der einzelnen Prismen oder Spirokristalle gebildet wurden, die bald seitlich aufeinander stiessen und sich so gegenseitig in der weiteren Ausbildung hemmten; nur an ihren inneren Enden vermochten sie einseitig weiter zu wachsen ” *, If I may be allowed to state the proposition in slightly different terms, the prismatic shell-substance (and, indeed, if my interpretation of the variations of the nacre, normal and patho- logical, are correct, the whole of the shell-substance) agrees with a spherocrystal in that it is composed of crystalline or crystallised substance which can only grow by the apposition of fresh layers deposited on a single surface, owing to the matter in solution only having access to one surface of the crystalline mass. When this surface is the outer surface of a sphere, a body with more or less of the characters of a spherocrystal results (e.g. Harting’s bodies and Pearls); where it is approximately a plane surface, as in the growth of the Molluscan shell, a structure such as the * Biitschli in 1908 (6, p. 26) explained his definition of ‘‘spherocrystals,”’ more especially with reference to the crystal-like prisms of Pinna (and by analogy of Margaritifera), as follows :— “ Wie aus den Darlegungen in meinem Werk von 1898 hervorgeht, verstehe ich unter einen solchen nicht ein Aggregat zentrisch angeordneter Kristallnadeln oder Einzelkristalle, was zwar die tbliche Anschauung ist, sondern ein einheitliches Kristallgebilde, in welchem die besonderen feinsten Struktur- verhiltnisse, die auch den gewéhnlichen Kristallen ihre charakteristichen Kigenschaften verleihen, nicht entsprechend einer Axe, sondern um ein Zentrum radiar orientiert sind. Wenn daher der Radius eines solchen Spharokristalls sehr gross wird, und man ein radiales Stiick desselben, weit entfernt von dem Zentrum, herausschneidet—und_ so verhalten sich etwa die Pinnaprismen—so muss dieses Stiick sich natiirlich wie ein gewéhnlicher Kristal verhalten ; obgleich die von mir gegebene Zuriickfiihrung auf einen Sphirokristall mit erossem Radius ganz zutreffend ist.” 304 DR. H. LYSTER JAMESON ON Molluscan shell results, the axes of its constituent elements being approximately parallel. (iu.) Zhe Nacre. This substance, which forms the bulk of the shell, and gives the shells of the genus Margaritifera their commercial value as Mother-of-Pearl, and the pearls their beauty, is stratified, and in it the calcium carbonate is divided into extremely minute bodies in the organic network. It is secreted by the outer surface of the mantle and body-wall. I will not attempt here to review the many writings on the structure of this layer. I can at present add little to the recent work of Romer (32), who has studied its structure and that of its decalcified conchyolin framework very thoroughly. The organic basis which gives it its form, and which retains its iridescence after the caleareous salts have been extracted, consists of a series of parallel lamelle, of extreme fineness, united to one another at intervals by radial connections, so as to form a series of minute flat or lenticular chambers, separated by organic walls of extreme delicacy. The calcium carbonate appears to be enclosed m these chambers in the form of little polygonal plates or lozenges. This structure is difficult to observe, owing to the distorting effect of the decalcification process, which, owing to the evolution of gas-bubbles, tears some lamellze apart and forces others tightly together. It becomes much more obvious in some of the abnormal and pathological varieties of nacre described as “repair-substance ” below, notably in “ granular repair-nacre.” I believe that the lustre (not the iridescence) of mother-of-pearl, and of pearls, is in great measure due to the fact that each of these tiny plates is a minute, biconvex lens; and that the extraordinary and indescribable character of the light reflected from the surface of a fine pearl is in part the cumulative expression of the action of these myriads of little lenses upon the light reflected from the surfaces of calcium carbonate and of conehyolin which underlie them. (iv.) Hypostracum, or Muscle-Attachment Substance. This curious substance has not secured all the attention it deserves. It has been described by several writers under the names Hypostracum (Thiele, 46), Stabchenschicht (Ff. Miiller, 29), durchsichtige Substanz (Ehrenbaum, 9; Tullberg, 47). I retain the name hypostracum, as emphasizing the distinct origin and characters of this layer, and as shorter and more convenient than ‘‘durchsichtige Substanz.” This hypostracum is a fine columnar layer forming the surfaces where the muscles are inserted into the shell (Pl. XXXIV. figs. 5 & 7, hy.; text-figs. 36 & 37). It is more transparent than the nacre—indeed, the iridescence and lustre of the muscle-scar is due to the nacre lying below and THE CEYLON PEARL-OYSTER. 305 shining through this “durchsichtige Substanz,” the substance itself not possessing the structure to which these optical properties are due, It is composed of columnar or fibrocrystalline needles of carbonate of lime (Stiibchenschicht, Miiller), but shows in places, in addition to its columnar structure, a distinct strati- fication parallel to the surface; this is seen also in the basis which remains on decalcification (Pl. XXXIV. fig. 5), I attri- bute this stratification to variations in the organic basis, which are probably independent of the form and structure of the crystalline needles. Hypostracum only oceurs where the specialised muscle-attachment epithelium is inserted into the shell, and, as the muscles move away from the umbonal region with the growth of the shell, it is quickly covered over by ordinary nacre which is deposited in the wake of the advancing muscle. In a section of the shell from the umbo through the adductor scar the hypostracum layer can be traced across the shell through the nacre from the scar to the umbo, the thickness of the over- lying nacre increasing as the umbo is approached. By means of this hypostracum layer, the wandering of the adductor muscle is recorded in the shell-substance (text-fig. 36, hy.). Text-fig. 36. AANA NU NAAN mT UNUU)LLA TOLD PRAY Ua a Margaritifera maxima Jameson. A young shell or “chicken shell” from Port Darwin, Northern Territory of Australia (London markets). Section from the umbo to the shell-margin passing through the middle of the adductor impression. p7., prismatic layer; A-—B, muscle-scar, covered with “ Hypo- stracum”; hy., the hypostracum layer, by means of which the migration of the muscle, from what is now the umbonal region, with the growth of the shell ean be traced; nae., nacre of the shell-margin, formed external to the muscle-sear; nac.’, nacre of the thick subumbonal region, deposited internally to the hypostracum. ‘Two-thirds of natural size. In the shell figured, a young example of the large white Australian Mother-of-Pearl shell (17. maxima Jameson), the hypostracum is 18-20 » thick over the muscle-scar, thinning out to 10 » and then to 4 or 5 w at the extreme outer edge of the scar, where the muscle has most recently made attachment. As this layer is traced backwards towards the umbo, through the nacre, it is found to get gradually thinner, just as the prismatic substance (which in this shell is about 1 mm. thick in the region of the adductor scar, and in the lip of very old examples of the Same species may be 2 or 3 mm. in thickness) is found to get thinner towards the umbonal region. These differences are no doubt associated with the relative ages and sizes of the animal at Proc. Zoot, Soc.—1912, No. XX. 20 306 DR. H. LYSTER JAMESON ON the respective periods, and with the relative rapidity of peri- pheral growth in young and older oysters. Text-fig. 37 shows the hypostracum of the same example (J/. maxima) enlarged forty times. Text-fig. 37. The inner limit of the adductor scar, in the same shell as that shown in text-fig. 36. hy., hypostracum; ac., nacre external to same; nac.’, nacre internal to same. X 40. . Exactly the same relations occur in J/. vulgaris, a section through the umbonal side of the adductor scar of which is shown in Pl. XXXIV. fig. 7. But in this example, an old thick Lingah shell from the Persian Gulf, 11 which, in all probability, peri- pheral growth, and consequently the wandering of the muscle, had ceased, the hypostracum is thicker, measuring 130 w in thickness. The hypostracum undergoes but little secondary thickening compared with the nacre. Hence, in thick massive shells ake M. maxima, where the newly forming nacre in the umbonal region and also towards the lip and around the muscle-scar out- strips the hypostracum in development, the muscle-scar is the thinnest part of the entire shell, except the extreme edge. This is well seen in text-fig. 86, in which figure the area between A and B represents the muscle-impression, but it is even more obvious in older thicker shells. Some interstratification of hypostracum and nacre occurs at the borders of the muscle-scars, where changes in the outline of the muscle ae taken place. This is figured by Tullberg in 1; ytilus (47, Taf. v. fig. 2). The same is shown for Margar itifer a vulgaris at hy.', hy”, in Pl. XXXIV. fig. 7. Felix Miiller (29, Taf. xxix. fig. 13 6) shows the lateral transition of this substance into nacre. I have observed the same thing in some of the “ Muscle-Pearls” described below. When decalcified the hypostracum leaves behind it an organic basis, which is somewhat different from the conchyolin of the rest of the shell in its reaction towards stains. This is of interest in connection with the view generally held that this layer, unlike the other calcareous parts of the shell, which are probably THE CEYLON PEARL-OYSTER,. 307 due to simple secretion, arises by a gradual transformation into shell-substance of the outer regions of the specialised epidermal cells which underlie it, 7. e. in the same manner as the Crustacean carapace and the outermost layer of the periostracum. It shows a well-marked striation perpendicular to the surface, the strix no doubt corresponding to the outlines of the spaces which were occupied by the needle-like fibrocrystalline bodies of caleium carbonate, and also at times indistinct lines parallel to the surface (Pl. XX XTV, fig. 5). In sections in the plane parallel to the surface this substance shows an alveolar structure. It sometimes shows a tendency to break up into segments, corresponding to the underlying epithelium-cells (Pl. XXXIV. fig. 5, hy.’). (v.) Hinge-Ligument. I do not propose to discuss the hinge-ligament here, as it has not the same direct bearing on the question of pearl-formation as the above layers, though leathery pearls, composed of this substance, are sometimes found (e. g. in JZ. maxima in Australia), (10) Tae SHeLi-sEecrerine Eprra ens. The ordinary shell-secreting epidermis of I. vulgaris, so far as I have been able to study it in the unsatisfactory material available, consists of columnar or tesselated cells (Pl. XXXV. a0;.6p:, igs 9, 0,ep.;.Pl. XXXVL fig) 11, oep.;, Pl XU. lig. 33, ep.), brick-shaped or palisade-like, according to the degree of contraction, in sections perpendicular to the surface, with a certain and variable number of goblet- and gland-cells. The nuclei of the epidermal cells are oval or spindle-shaped. These cells are attached to the subjacent tissues by a basement- membrane of delicate fibrille which distinctly marks the boundary between the epidermal epithelium and the subjacent tissues. Beneath this epidermis is a characteristic granular parenchyma (Pl. XXXV, figs.8&9; Pl. XXXVI. figs. 10 & 11; Pl. XXXVIT. fig. 14; Pl. XLI. fig. 33, par.), which contains a great variety of elements, some being comparable to the “ Rundzellen” and “ Langer’schen Blasen” described by List (27) for the Mytilidee, some being dark-staining, apparently glandular elements that open out between the epithelial cells (fig. 33, gl.). As observed by List (27), this epithelium and the underlying tissues are excessively variable in their characters. Over the surface of the muscle-attachment the epidermis is different (Pl. XX XIII, figs. 4, 4a; PL XXXV. fig. 8, m-ep.). Here it consists of columnar cells, usually about 10-12 w long and 2-4 » broad, which pass over basally without any distinct dividing-line into the muscle-fibres. Whether the transition is direct, or whether in fact a connective-tissue junction is present, cannot be determined from the available preparations of Margaritifera vulgaris; but in Mytilus edulis there is a distinct connective-tissue layer (fig. 5, c.t.), the fibres of which, 20* 308 DR. H. LYSTER JAMESON ON continuous with the bases of the epidermal cells, are attached to the ends of the muscle-fibres (musc.), which may be produced out into tails. Tullberg recognised that such a junction was present. In Margaritifera vulgaris the attachment epithelium-cells may have one or several tails, probably also of connective-tissue character, passing over into as many muscle-fibres. Distally these epidermal cells broaden out somewhat, ending in a clean-cut surface, which may be represented in section by a clear zone forming a slightly acute angle with the sides. The nuclei, which are oval and about 3-4 p long, are situated in the middle of their length. It is possible to make out, in some cases, a striation of fhiene cells in the direction of their ‘long AXES. Occasionally the distal surface is raised into processes and papille, but this may well be a result of imperfect fixation of the tissues. These cells stand out as stiff, independent, almost bristle-like entities, and are probably hard and tendinous in character. They are frequently preserved in old preparations in which all traces of the structure of the ordinary epithelia have disappeared. In some cases they seem to have been drawn out in the fixing process; thus the longest cell shown in Pl. XX XIII. fig. 4a measured 26». It seems possible that in the shrinkage consequent upon fixation the majority of the elements here had broken away from the shell, but that this particular cell had remained attached and was consequently fixed in a state of extension. This figure shows that the connective-tissue elements extend up between the bases of these cells. This epidermis is very closely adherent to the specialised shell- layer (hypostracum) to which it is attached, and the connection seems to be between the cells and the organic basis of the shell. Thus, in decalcifying a piece of the shell of Mytilus with the adductor muscle attached, the hypostracum remained adherent to the epithelium and tore away from the rest of the shell (Pl. XXXIV. fig. 5). (11) SHELL-SECRETION. I will not attempt to survey the writings of previous inves- tigators on this subject. This has been ably done by Stempell (45), whose review contains a full and lucid discussion of the question. The general trend of opinion now seems to favour the theory dating back to Reaumer, 1709 (31), and held by Tullberg, Ehrenbaum, Moynier de Villepoix, and the majority of recent French and German investigators, that the shell (except the outermost layer of the periostracum and the hypostracum) is formed from a fluid secretion, rather than the theory specially associated with Huxley’s name (24) that the shell is derived from a succession of fully developed skins or cuticles, shed as membranes by the underlying epidermis. THE CEYLON PEARL-OYSTER. 309 ' The outermost layer of the periostracum (which in Margariti- Jera is a negligible quantity) and the hypostracum probably arise by direct transformation of the outermost portions of specialised epidermal cells, and on this account it may prove necessary to draw a sharper morphological distinction between them and the rest of the shell than has hitherto been done *. The prismatic layer and the nacre, together with the inner layers of the periostracum, more probably arise as a secretion which first hardens into a membrane 7d situ, and then forms the delicate skin which Huxley observed between the mantle and the shell in the freshwater mussels. It would appear that the lime-salts and albuminous fluid which hardens to form the conchyolin are independent of each other, and may be secreted in varying proportions. Where these two constituents are secreted under circumstances which inhibit the control of the shell-secreting epidermis, or where the secretion takes place so copiously and rapidly that the epidermis is unable to regulate the deposition (as in the patho- logical cases described below), lime-salts are precipitated in a columnar form, much as in Harting’s bodies, and, concurrently with this, the albuminous fluid is transformed into an insoluble substance resembling conchyolin. The process of shell-secretion at the rapidly growing edge of the shell resulting in the formation of the prismatic layer—which in Margaritifera vulgaris measures as much as 1 mm. or more in thickness—is probably in some degree analogous to the process of secretion of repair-substance, the epithelium exercising comparatively little control over the arrangement of the elements. But in the case of the nacre it is different. Here the epithe- lium seems to exert a definite and very strict selective influence resulting in the finely stratified and chambered structure which ean, I think, best be interpreted as arising from rhythmically intermittent secretory action on the part of the controiling epidermis. Any disturbance of the normal rhythm of this secretion, ¢. g. the stimulation of an intrusive particle between shell and epidermis, results in the formation of the irregular substances described below, such as granular repair-nacre, the several varieties of columnar repair-substance, or the amorphous non-calcified substance. It would thus seem as though the structure of the shell- substance, and its variations, normal and pathological, could be expressed in terms of the proportions of lime-salts and organic * The difference between the outermost layer of the periostracum and the hypo- stracum on the one hand, and the remainder of the shell on the other, the former parts arising by direct cell-transformation or cuticularisation of cell-protoplasm, the latter as a secretion poured out by the cells, suggests a line of inquiry that might yield interesting results. Can these two constituents of the shell be separated morpho- logically and phylogenetically, and, if so, can the former be regarded as in any sense homologous with the cuticular exoskeleton of an ancestor common to Mollusca and Arthropoda, the latter being a subsequent addition peculiar to the Mollusea. associated with their more sedentary modes of life, which has now, for all practical purposes, replaced the more strictly cuticular element as an exoskeleton ? 310 DR. H. LYSTER JAMESON ON salts secreted and of the periodicity of the secretion as determined by the control, or loss of control, of the secreting epidermis, Tn fact, if my interpretation is correct, the processes involved in the building of the shell are the usual chemico-physical ones which govern crystallisation in colloidal media* controlled and limited by the time-factor which is a function of the activity of the living cells. It is less easy to imagine the conditions which determine the transformation of the fluid albuminous secretion mto the leathery conchyolin. One is naturally tempted to postulate a chemical transformation asa direct or indirect result of the action of nascent CaCO,, as in the case of the calcoglobin in Harting’s bodies (12); but the formation of this substance apart from the lime-salts, e.g. in the inner layers of the perio- stracum and in amorphous repair-substance, and in the case of shells grown in lime-free media (Moynier de Villepoix, 28, p- 122), seems to negative this; and it may well be that this change to an insoluble albuminoid is directly brought about by the action of the secreting cells themselves, or follows from the chemical composition of the secretion as shed. (12) ABNorMAL AND ParnoLocicAL PHAsEs OF THE SHELL-SUBSTANCE, For a study of the beginnings of Ceylon pearls, a consideration of the variations in the shell-substance, when it is secreted under abnormal conditions, either on the surface of the shell or of a growing pearl, is of importance. Where the normal rhythm of the process of shell-secretion 1s interrupted, e.g. by injury to the shell, or the intrusion between the epithelium and the nacre of a foreign particle or by other disturbances less easy to explain, certain irregularities in the process of secretion occur, resulting in an altered product. Tn the simplest case such a disturbance results in a modification producing a granular appearance of the conchyolin-layers of the nacre. This modified substance I propose to call “ granular vepair-nacre.” In sections made through this substance, after decalcification, the normal stratification is obscured by a highly granular appearance which seems to be due to an_ infinite number of connections between the successive conchyolin-layers resulting in a distinctly alveolar membrane. This is shown in text-fig. 38 (rep.nac.), which is taken from an artificial “Dlister ” produced by the writer in Margaritifera margaritifera after the “ Linneus” method, in British New Guinea in 1899. The foreign body was inserted near the mantle-margin, and the mantle secreted first a double layer of the prismatic subtance, * Biedermann (2), p. 171, recognises that the structure of the shell is essentially reducible to crystallisation processes, the influence of the cells being limited to the composition of the fluid, and perhaps the orientation of the primary centres of crystallisation, But I would add to these influences the periodicity of their action. : THE CEYLON PEARL-OYSTER, 311 and then nacre, which, at places, showed the characters of “ granular repair-nacre.” Text-tig. 38. Margaritifera margaritifera Linneus (Black-lipped Mother-of-Pearl Oyster). Part of an artificially produced blister. pr., prismatic layer ; Sér., horizontal dividing membrane of conchyolin in same; nac., nacre; rep.nac., granular repair-nacre. (Preparation VIII.) Pl. XL. fig. 29, from the “repair-membrane” formed by M. vulgaris over a hole in the shell (umbonal region), shows the same substance at ér.’ passing over on the one hand into columnar repair-substance, on the other into nacre. The same substance is seen at ér. Pl. XLI. fig. 30 (rep.nac.) shows the same substance, secreted at the point of junction of two pearls (from one of Dr. Kelaart’s specimens of Jf, vulgaris). Here it was secreted as a result of disturbances following upon the fusion of the two pearls and the absorption or calcification of the intervening tissues. The granular repair-nacre in the preparation shows in places a distinctly columnar structure, indicating a transition to the columnar repair-substance ; such a transition is still more obvious in Pl. XL. fig. 29. The same granular repair-nacre is seen in Pl. XX XV. fig. 9, Pl. XX XVII. fig. 15, and Pl. XX XVIII. fig. 18, surrounding the central cavities of “‘ muscle-pearls,” where unduly rapid secretion might well be expected, and in Pl. XXXIX. fig. 23, where a hypostracum-pearl (“ calcospherule,” Herdman) is in process 312 DR. H. LYSTER JAMESON ON of being coated over with nacre. The same substance is well shown in Pl. XLI. fig. 35 and Pl. XLITI. fig. 43 (gr.). In the last-named case it is seen to pass over on the one hand into nacre, on the other into columnar and amorphous repair- substances. The next form of repair-substance is much more variable, and occurs in several distinct, though intergrading forms. I propose to call this “ columnar repair-substance,” in view of the calcium carbonate being crystallised in columns. Columnar substance resembles, more or less, the prismatic layer of the shell—indeed, it is probable that Rubbel (33, p. 171) had a substance analogous to this columnar substance before him when he stated that the outer epithelium of the mantle of Margaritana is capable, in repairing the shell, of producing the prismatic substance which is normally only the product of the mantle-margin. (In the same way, he treats as “ peri- ostracum” the non-calcified material secreted under similar conditions, which I describe below as “‘amorphous repair- substance ”.) * In its simplest form columnar repair-substance consists of parallel needle-like rods of carbonate of lime (which Steinmann (43), speaking of Harting’s bodies, has aptly called “ fibro- crystalline’) deposited in an organic conchyolin-matrix, which, when the calcium carbonate is removed by acids, and a section 1s cut at right angles to the surface, presents a palisade-like appear- ance, due to the septa of conchyolin between the calcareous rods (Pl. XL. fig. 29; Pl. XLI. fig. 30, col.). In horizontal section this conchyolin has a honeycomb-like structure. All kinds of variations occur in the coarseness or fineness of the calcareous elements and the organic framework. This substance is frequently formed on the surface of the shell or of a pearl when disturbances arise in the rhythm of shell- secretion. In Pl. XL. fig. 29 it is seen in the repair-membrane formed over an injury caused to the shell by a boring parasite. In PI. XLI. fig. 30 it. is seen (col.) in the angle between the surfaces of two “pearls which have become oy attached together. 120 cb fig. 31 shows the same substance developed under conditions similar to those existing in fig. 30. This figure is a drawing of a section through the suture between two pearls which have become secondarily fused together. The pearls themselves, with the intervening suture, are shown in Pl. XLIV. fig. 49; the end of the suture, where the curvatures of the two pearls diverge, in fig. 31. In the entire object, examined in oil of cloves (fig. 49), the suture was represented by a yellowish- brown line, the colour being due to the dead remains of the cellular membrane which originally separated the two pearls. * While these substances are perhaps not strictly separable aye ede on chemical and physiological grounds, I think it is well on morphological and patho- logical grounds to emphasize the distinction. THE CEYLON PEARL-OYSTER. alte The membrane consisted of the lining epithelia of the two sacs, and a layer of parenchymatous tissue between these two epithelia. The epithelia, and even the individual cells of the parenchyma, can be detected in some places (Pl. XLI. fig. 32). If we try to trace the steps resulting in the condition figured on Pl. XLIV. fig. 49 and on Pl. XLI. fig. 31 (¢.e. to survey the story of the formation of a double pearl), we may assume that they were as follows. As the two neighbouring pearls, each enclosed in a sac, grew in size, by the addition of fresh layers, they exerted a pressure on the intervening tissues, resulting in reduced circulation and consequent malnutrition which began at the first point of contact and extended outwards. Thus the contiguous surfaces tended to become flattened (fig. 49), and the intervening tissue, consisting of the epithelia of the two pearl- sacs and a small amount of connective-tissue between them, finally ceased to be functional, died, and was preserved as a yellow membrane (Pl. XLI. fig. 32). At the periphery of the area of contact, where the curvatures of the two pearls diverged and were separated by a wedge-shaped plug of tissue, nacre- secretion continued longer, the last efforts of the epithelia being represented by mac. and nac.' in fig. 31. Finally, the epithelium ceased to control the deposition of its secretion, and, with the shrinkage of the atrophied tissues a space occurred on each side between the nacre and the epithelium, into which an extravasation of organic matter and salts occurred. The salts precipitated themselves in the form of columns or raphides with their bases apparently in or on the epithelia, and con- currently with this precipitation the soluble organic substance became converted into the conchyolin framework between the prisms, analogous to the “ calcoglobin” framework of Harting’s bodies, derived from egg-albumen when calcium carbonate is precipitated in it. Lastly, the epithelia and intervening con- nective-tissue died and probably underwent irregular calcification, breaking away from the still functional tissues and becoming incorporated in the substance of the pearl. The still functional tissues now formed a single sac surrounding the two pearls, and quickly enveloped them both in a common nacreous covering. Similar processes can be postulated to account for the condition shown in Pl. XLI. fig. 30. Here, between the curvatures of the surfaces of the two contiguous pearls, there was a triangular plug of tissue, which for some time remained attached to the degenerated membrane which separated the pearls. Its epithe- lium gave rise before it broke away to granular repair-nacre (rep.nac.) on the right, where the disturbance was presumably least, and to a small amount of columnar repair-substance (col.) on the left. Then it broke away from the degenerated and dead membrane between the pearls and retreated rapidly, exuding as it went the albuminous fluid, which, being secreted at a much greater rate than the lime-salts, was practically devoid of lime 314 DR. H. LYSTER JAMESON ON and formed coarsely stratified amorphous substance (am.), broken by cleft-like cavities. Later on, when the retreat of the plug of tissue was Jess rapid, this aiorphous substance passed over into columnar substance (é.) and granular repair-nacre (¢.'), and finally gave place to the nacre (nac.’) of the common investment of the compound pearl. The columnar repair-substance varies enormously, and passes over imperceptibly into ‘“‘amorphous substance” or lime-free conchyolin, granular repair-nacre, ordinary nacre, and the prismatic substance of the shell. For example, the repair- membrane, a part of which is shown in Pl. XL. fig. 29, showed an immense number of variations from place to place. In some parts a second layer of amorphous substance was interpolated between the columnar layers; in others the columnar substance passed over into a coarsely alveolar substance with irregular cavities, some of which penetrated into the amorphous substance. In yet other spots the amorphous substance passed over through granular repair-substance into nacre. Columnar substance is frequently stratified, consisting of a number of consecutive layers. This is seen at col.’ in the repair- membrane figured at fig. 29. It is also shown in the pseudo- nucleus of the pearl shown on Pl. XL. fig. 28 and Pl. XLIV. fig. 49, and in the pearls from the Persian Gulf in Pl. XII. figs. 33 & 34. In the former of these last-named instances it occurs immediately around the central cavity, in the latter case interstratified and intergrading with the nacre. In Pl. XLIIT. fig. 43 (col.) it is seen passing over on the one hand into granular repair-nacre, on the other into amorphous repair-substance. The same stratified columnar substance is well shown in Pl. XLV. fig. 51, where it forms a curious flaw running through the substance of a pearl. Apart from this direct stratification, the columnar repair- substance may have an internal alveolar structure such as is shown in Pl. XLIT. figs. 36, 37, & 38. Figs. 40-42 on the same Plate, taken from the pearl shown in Pl. XLVI. fig. 57 (a brown pearl composed of prismatic shell-substance), show the transition from amorphous repair-substance to columnar repair-substance’ (figs. 41, 42, col.), and from the latter to the prismatic layer of the shell (fig. 42, pr.). The third variety of repair-substance I call amorphous repair- substance. In its typical form this substance is seen at am. in Pl. XL. fig. 29, where it is obviously the result of the first effort of the molluse to close the injury to the shell, and in Pl. XLI. fig. 30, where it is the product of a fully functional epithelium, retreating rapidly and leaving its secretion in itswake. It shows little or no structure under ordinary magnifications, but is usually faintly stratified. It may contain cavities, arranged in rows parallel to the secreting-surface, and with at times also a radial arrangement. These cavities typically contain carbonate of lime. Pl. XL. fig. 29 @ (Margaritifera vulgaris, Lingah Shell, Persian 9 THE CEYLON PEARL-OYSTER, 315 Gulf) shows this substance formed as the first step in the development of a new layer of prismatic substance to cover over the tube of the worm Leucodore, which has entered between the mantle-margin and the shell, as is its wont. Here the mantle- margin, reacting to the stimulation of the parasite, has retreated and secreted a new “lip” to exclude it. This lip, like the normal lip, consists of the prismatic layer of the shell, but the irregularly secreted first layers of it consist of amorphous substance, containing alveoli in which a scanty supply of calcium carbonate was deposited. The amorphous substance frequently occurs in the centres and around the central cavities of pearls, where it doubtless represents the first matter which the mollusc shed into the cavity. It probably corresponds to the “ Theile des Schalenepidermis ’ si recognised by von Hessling (18, p. 313) in the nuclei of pearls, and the “‘ Kern von Chitinsubstanz” referred to by Pagenstecher (30, p. 502), and perhaps to the ‘“ Gelbbrauner Substanz” of Rubbel (34, p. 412). The amorphous substance shows little receptivity to stains. It passes over sometimes into columnar substance (Pl. XLI. fig. 30, é.), sometimes into granular repair-substance (Pl. XL. fig. 29, tr., tr.'; Pl. XLI. fig. 30,¢r.'). It also sometimes inter- grades with a substance resembling the prismatic layer (Pl. XLII. fig. 41). Similar intergradations with prismatic substance were shown in some parts ‘of the preparation from which Pl. XL. fig, 29a is drawn. Pl. XLII. figs. 40-42 are of interest as showing all manners of intergradations between amorphous, columnar, and prismatic substances, the different structures shown being apparently mainly dependent upon the proportions of calcium cabénuta present. Thus we have in this pearl, which, owing to the impermeability of the amorphous substance, was imperfectly decalcified, tracing the layers from inside out- wards: (1) a plug of nuclear matter of doubtful origin con- taining well-marked crystals (fig. 40, mw.)—these are true crystals (rhombohedra); (2) a layer of amorphous substance, passing over into typical simple columnar repair-substance (fig. 40, col.) ; (3) numerous layers of amorphous substance (figs. 40, 41, am.), some layers being quite lime-free, some having scattered elect containing calcium carbonate, some showing thew cavities in radial rows, leading up, by transitions, to regular columnar substance (figs. 41, 42, col.), which differs from the prismatic substance proper (fig. 42, pr.) only in the smaller diameters of its constituent elements, a difference which, in view of the variability of the sizes of the prisms in the shell itself, is com- paratively unimportant. Again, the transition from the abnormal repair-substances to nacre in the pearl shown in Pl. XLV. fig. 52, col., and Pl. XLII. fig. 56, col., is equally striking. This is shown in detail in Pl. XLII. fig. 43. At nz. is the outer wall of the sphero- crystalline or columnar pseudo-nucleus of the pearl. At rac. is 316 DR. H. LYSTER JAMESON ON shown the normal nacre of the pearl. The first-formed layers of nacre are incomplete, passing over into this area of repair- substance, and all stages of transition may be seen, corresponding to the gradually increasing control exercised by the secreting epithelium. At first, amorphous substance (am.), alveolar in places, was secreted, no doubt with irregular crystallised bodies in the alveoli, some of which are actually preserved in the preparation, owing to incomplete decalcification. Peripherally this gave place to columnar substance (col.), which acquired a finely alveolar structure, and passed over, through granular repair-nacre (g7.), into normal nacre (nac.'), the layers of the conchyolin of which gradually merge into the horizontal markings of the granular substance. The amorphous substance in this preparation varies from layer to layer in the degree to which it is alveolar; at some places it might better be described as coarsely columnar substance. Amorphous substance seems to be the first product where the shell is perforated and the mantle makes a sudden effort to close an opening to the exterior. In such cases it may be secreted so copiously that a tough leathery skin results, with little or no lime- salts in it (Pl. XL. fig. 29, am.). It is likewise secreted in layers when a break occurs in the nacre-secretion of a pearl or of the shell, owing to a pathological extravasation of cellular matter (Pl. XXXVIIL. fig. 17, am., am.'). These facts suggest that the organic basis of the shell is the constituent the secretion of which varies in quantity, the secreting-tissues (perhaps the granular subepithelial parenchyma in WMargaritifera) contaiming a reserve of this material which can be poured out profusely when the shell is injured. It would seem that the lime-salts, on the other hand, are secreted more regularly, so that the mechanism for furnishing these cannot keep pace with that which yields the organic substance when the latter is called upon to make a special effort to repair damage. The resemblance of the inner layers of the periostracum (in forms with a thick periostracum) to amorphous repair-substance may perhaps be explained by postulating the absence or inhibition of the lime-secreting mechanism in the underlying tissues. That the secretion of calcium carbonate could not keep pace with that of the organic substance, when the latter is produced in large quantities, is easy to understand in view of the very small proportion of CaO in the blood of Mollusca, and indeed of all invertebrates that have been investigated. According to Griffiths (quoted by Biitschli, 6, p. 62), the CaO in the blood of a number of bivalves examined varied from 0°032 per cent. in Anodonta to 0:067 per cent. in Jytilus. Amorphous substance is seen in the pseudo-nuclei of pearls in Pl. XX XIX. figs. 20 & 21, and Pl. XL. figs. 24, 26, & 27; figs. 20, 24, & 27 showing particularly well its continuity and intergra- dation with the organic basis of the columnar repair-substance. In the centre of a pearl it may contain, in addition to the THE CEYLON PEARL-OYSTER. S17 central cavity, secondary cavities in its substance, in which organic particles are lodged (fig. 20). The variations of coarsely alveolar structure which amorphous substance shows (e.g. Pl. XL. fig. 29 @ and Pl. XLII. figs. 40 & 41) recall those structures which Biitschli (6, Taf. iii. figg. 20-33) describes in the spherocrystals of (?) Trydimite formed when the siliceous concretionary substance of the Bamboo (known as Tabaxir or Tabasheer) is heated; this structure is probably in great measure the expression of the physical conditions (surface tension, etc.) which prevail when two substances in solution or in a colloidal state separate from one another to form a spherocrystalline mass. Pl. XLII. figs. 37 & 39 are of interest as showing another variation of the nacre, in the direction of columnar substance. In this variety of nacre, the conchyolin-layers are connected by a number of thickened junctions, which tend to occur in groups and which are arranged in radial rows. In surface view these junctions appear as groups of dark spots on the conchyolin-layers ; in radial section they are as shown in fig. 37, and can also be seen in Pl. XXXVI. fig. 13. These junctions seem to be thickenings of the walls which normally connect the several conchyolin-layers of the nacre to one another; they may, in fact, be regarded as local exaggerations of the condition described as “ granular repair-nacre.” It is interesting to note the peculiar manner in which these repair-substances occur in Japanese ‘Culture Pearls.” This name was given by the late Professor Mitsukuri (27 ¢, pp. 283-4, pl. xi. fig. 1) to pearl-like bodies—‘“ blisters,” as they would be called on the Australian fisheries—which are artificially produced in the Japanese Pearl-Oyster, Margaritifera martensit * Dunker. The production of these “Culture Pearls” is an extensive industry supporting about 100 persons, and is carried on by Mr. Mikimoto on leased areas of sea-bottom in the Bay of Agu, Shima Province, on lines originally suggested by Prof. Mitsukuri in 1890. It has been going as a commercial success since 1898, when the first crop of ‘* Culture Pearls” was marketed. In 1905 the number of oysters operated on per year was from 250,000 to 300,000. The process, which is protected by patents, is analogous to that adopted by the Chinese in the production of ‘ Buddha Pearls” in the fresh-water mussel, Dipsas plicatus, and to the method discovered by Linnzus in the 18th century (see Herdman, 16 a), and consists in the introduction between the shell and the mantle + of a bead of nacre, which in due course (the time allowed in Japan is four years) becomes thickly coated over with nacre, * This mollusc is regarded by some naturalists as a local race of M. vulgaris, to which it is undoubtedly very closely related. Whether it be called M@. martensii or M. vulgaris var. martensii is largely a matter of individual taste. + This is apparently done vid the edge of the shell and not by drilling as in the Linnzeus process. 318 DR. H. LYSTER JAMESON ON forming a hemispherical, or sometimes rather more than hemispherical pearl-like excrescence, attached to the shell by its base. These “Culture Pearls” are produced in large numbers, and find a ready market for purposes for which “ half-pearls” are used. ‘They are now familiar objects in Europe *. Text-figure 39 is a section of a Japanese “Culture Pearl,” which [ purchased in London, while still attached to the shell, and decalcified. Text-fig. 59. TW. “ TUES ES = SE SS eee eee Za LF SSS —— ; TATA a AANA ITT MN ATTAIN pr col. cot! Fnac. G7- Section through a decalcified Japanese “Culture Pearl” still attached to the shell. nu., the artificial “ nucleus,’ a bead of nacre, the Jamine of the nacre being cut transversely ; pr., prismatic layer; nac., origimal nacreous lining, which existed before the nucleus was introduced ; nac.', more recent nacre, lining the shell and extending over the “nucleus” to form the “Culture Pearl,” secreted after the introduction of the nucleus; nac.’’, nacreous layers where the lining of the shell is carried over the nucleus; col., col.’, repair-substance secreted im a zone around the point of contact between nucleus and shell, where the deposition of the shell-substance was not controlled by the mantle; g7., granular matter, perhaps of foreign origin or of the nature of amorphous substance. X 10. The ‘‘ nucleus” has been very skilfully introduced, so that there is practically no trace of “dirt” between it and the nacreous layer with which it is invested, as is so often the case in the “« blisters ” which have been produced by naturalists and experi- menters from time to time. Moreover, the disturbance of the normal functions of the mantle has been so slight that, in the * Needless to say, these bodies are not “ Pearls,” biologically speaking, but belong to the class of structures to which I have applied the name “ blisters,” familiar on the Australian Fisheries and in the Trade. Various naturalists have produced such bedies from time to time. Ihave recently seen some very beautiful ‘ones produced in Margaritifera maxima, and I myself produced some presentable ones in Margaritifera margaritifera in Papua in 1899-1900. But although attempts have been made, and are still being made, to do this on a commercial scale, T am not aware that commercial success has yet been achieved anywhere else than in Japan; indeed, I think that the combination of circumstances which has led to the success of the Japanese enterprise—viz., skill, patience, and intelligence, backed by the best scientific advice and supported by cheap labour—has generally been lacking in other ventures. I may add that the price that could be obtained for the best of these gems is insignificant compared with the value of a real pear] of like size. No THE CEYLON PEARL-OYSTER. 319 particular sections that I examined, there was a marked absence even of the repair-substances. But in the zone immediately around the point of contact between nucleus and shell, where, when the nucleus was introduced, the epithelium of the mantle was presumably unable to fit closely against the surfaces, it is otherwise. Here, on examining the whole “ Pearl” as a trans- parent object after decalcification, an opaque ring or zone was distinctly visible. This was due to the presence of granular matter, perhaps derived from the exterior, perhaps from the tissues of the animal (text-figs. 39 & 40 B, gr.), and to very irregular columnar and amorphous repair-substance (col., col.’), This columnar substance is shown in greater detail in text-fig. 40, A & B, corresponding respectively to col. and col.’ in text-fig. 39. In text-fig. 40, A, in the niche between the nucleus and the shell, where the mantle-epithelium could not reach, we see the product of its secretion consolidated away from the influence of the epithelium. Here the columns, instead of forming the character- istic palisade-like structure, with their long axes perpendicular to the secreting surface, are arranged in groups suggesting incomplete spheerocrystals. The curious fan-like arrangement which the columns take on in text-fig. 40, B, suggests that the repair-substance arose through an extravasation of the shell-forming fluids at the point a, the layer nac.’ representing the first normal nacre, secreted by the mantle when it occupied that position, the irregular columnar and amorphous substance being due to the consolidation of the secretion which filled the space, triangular in section, which lay between the nucleus (nz.), the shell (nac.), and the mantle; the position occupied by the last named being represented by the layer of nacre marked nac’'. (13) Varreties or Ceyton Pears. Pending a classification based on the nature of the causes which give rise to the formation of the pearl-sac, I propose, following Herdman, to separate the pearls which I have examined in or from the Ceylon Pearl-Oyster into two main groups, accordingly as they typically occur clustered in the neighbourhoods really satisfactory proof has ever been given that free spherical “pearls” can be produced in this way, though Prof. Mitsukuri (7. c.) says that there are some hopes that this will be done. There is no theoretical reason why a modification of the Japanese or Linnean operation should not be devised which would achieve this end— indeed, there is some reason to think that Linneus actually did produce some round “pearls” and not only “blisters.” But such bodies, if produced, would not be “pearls ” in the strict biological sense, though it is quite likely that they would be marketed as such in quantities before the difference was detected. Since writing the above, I have been informed by Mr. Toyozo Kobayashi, Professor at the Tokyo Higher Technological College, who is associated with Mr. Mikimoto in his enterprise, that perfectly free “ pearls” have been produced by these methods within the last two years, but so far only exceptionally, and on a scale so small as not to be applicable commercially, 320 DR. H. LYSTER JAMESON ON of the muscular insertions or singly in the non-muscular parts of the body-wall and mantle. Text-fig. 40. A. The irregular columnar and amorphous substances, shown at col. in text-figure 39. nac., nacreous lining of the shell; xac.’, nacre deposited shortly after imtro- duction of nucleus, passing over into the repair-substance (é7.) ; nac.’’, nacre continuous with the layers investing the nucleus; col., col.’, columnar repair- substance; am., amorphous repair-substance. XX 35. B. The fan-shaped mass of repair-substance, shown at col.’ in text-figure 39. nu., the introduced “nucleus”; naec., the original nacreous lining of the shell; wac.’, the first layers of nacre, separated after the introduction of the nucleus; col., columnar repair-substance; am., amorphous repair-substance ; gv., granular matter, perhaps of extraneous origin, 100. THE CEYLON PEARL-OYSTER. BP all LT adopt Professor Herdman’s term ‘“ Muscle-Pearls” for the former class, while for the latter category I propose the name ‘“* Parenchyma-Pearls ” *, because they occur typically in the parenchymatous subepidermal tissues of the non-muscular parts of the body-wall and mantle, or, by secondary displacement, in the more deeply seated soft tissues. This group corresponds, I think, to Herdman’s “ Cyst-Pear]s,” but I prefer not to adopt the latter name, as, if the word “ cyst” refers to the encysted Cestode, which Herdman associated with pearl-production, I have been unable to trace the connection between it and the pearl; while if it refers to the pearl-sac or “cyst,” this is found around all pearls, including muscle-pear's. There is some reason for believing that some parenchyma-pearls arise from causes different from those that lead to the formation of muscle-pearls, and, indeed, it is quite possible that parenchyma- pearis have several modes of origin, as Herdman believes ; but, on the other hand, their differences may be due in great measure to the different parts of the tissues in which they originate, and it is certainly quite impossible, in many cases, to say, from the structure of a pearl and of its nucleus and pseudo-nucleus, whether it is a “ muscle-pearl” or a “ parenchyma-pearl.” With regard to Herdman’s “ Ampullar pearls,” I cannot regard this group as of equal value to the above two classes, as, in my experience, so far as it goes, the “Ampulla” is of secondary origin, due to the absorption of the tissues intervening between the pearl and the shell, and to the epithelium of the pearl-sac and that of the outer face of the mantle thus becoming continuous. Before going further I had better explain a term that I am introducing into this paper. I am restricting the word ‘“‘Nucleus,” as applied to the body found in the centre of a pearl, to those bodies which appear to be either of foreign origin or derived from the pearl-oyster otherwise than through the agency of the shell-secreting mechanism. To the~ bodies formed by the shell- and pearl-secreting mechanism, composed, asa rule, of different kinds of repair-substance (bodies which have no doubt often been wrongly mistaken for objects of foreign origin), I propose to apply the name “ Pseudo-nucleus.” I have endeavoured to be consistent in the use of these two terms, but, as is so often the case in biological matters, there is at times a difficulty in defining a sharp boundary-line between the objects to which they are respectively applied. A. Musele-Pearls. I have set out above (p. 267) Professor Herdman’s views on the nature and origin of these. Briefly recapitulated, they are the following. From some unknown cause, minute calcareous * Rubbel (34 a) applies the term “ Mantelperlen” to th se bodies, a term which I prefer to mine, though it is too late to alter the nomencla ure in this paper. Proc. Zoou. Soc.—1912, No. XXI, 21 322 DR. H. LYSTER JAMESON ON depositions or caleospherules * arise in the tissues, close to the attachments of the muscles to the shell. Ectoderm-cells may “migrate to the source of irritation, and thus be responsible for the deposition of a pearl.” No explanation of the origin of these calcospherules is given, but Mr. Southwell thinks it is ‘almost eertain that they are depositions from the blood,” and refers to them elsewhere as ‘‘ of excretory origin ” (42). I have been led by my observations to take a quite different view of these “ caleospherules” 7, and as their origin is so closely related to that of Muscle-Pearls, I cannot do better than begin the present section of my paper with an account of their struc- ture and origin. According to my view, Prof. Herdman’s “ caleospherules ” are not free concretions at all, but are minute pearls, composed of hypostracum ; and I propose, therefore, to call them “ hypostra- cum muscle-pearls,” to separate them from ‘“ nacreous muscle- pearls.” As stated by Herdman, these bodies occur close under the epidermis (unless secondarily displaced, e. g. by the addition of new ones), and I usually find them in the region where the muscle-attachment epithelium passes over into the ordinary shell- secreting epidermis of the mantle. A group of these hypo- stracum-pearls is shown on Pl. XX XIX. fig. 22, which represents a portion of the mantle-musculature of one of the unlabelled specimens in the British Museum, examined entire in oil of cloves. The same pearls, decalcified, are seen in fig. 23. These little bodies measured from 0°02 to 0°5 mm. in diameter. In Pl. XXXVIII. fig. 19 similar bodies, hy.p., are seen in a section along with ordinary nacreous muscle-pearls; while single indi- viduals are shown in Pl. XXXIX. figs. 21 & 21a@and Pl. XL. fig. 25. Sections ground from these bodies, or cut from the organic residues left when they are decalcified, show them to be composed of the same substance as the hypostracum of the shell. They consist of caleium carbonate, in fine fibrocrystalline form, showing radial and also concentric markings, with a small central cavity (Pl. XX XIX. fig. 21a). Decalcified they also resemble hypo- stracum in all details of structure and reaction to stains (fig. 2D) cost Ulver organic basis stains more blue with hematoxylin than the organic parts of the other shell-substances, and takes up carmine more deeply. Their alveolar structure is also much finer than that usually found in the columnar varieties of repair- substance, so fine, in fact, that in surface-sections the reticular structure seems almost like that of the protoplasm itself. As has been observed in the hypostracum of the shell, this substance sometimes passes over into nacreous conchyolin laterally. The * This word is presumably intended to convey the same idea as the word “ eoneretion’’ adopted by me (25) in 1902, 7. e. a sphrocrystal-like body arising in the tissues otherwise than by epidermal secretion; and therefore analogous to cholesterin calculi, etc. (ef. Harting’s “ Calcospherites,” 12). +1] find that Rubbel (34 a), working on the freshwater Pearl-Mussel, Margaritana, has arrived independently at the same view of the nature of these bodies as that here propounded. THE CEYLON PEARL-OYSTER. 323 central cavity of a hypostracum-pearl may contain granules of doubtful origin, as in the case shown in fig. 21, but it is frequently quite empty. At times the organic basis of one of these hypo- stracum-pearls, when decalcified, shows a tendency to break up into segments, especially at its inner surface; the segments in such cases probably correspond to the outlines of the original secreting-cells ; indeed, in such cases the whole body may have an almost cellular appearance, which is not surprising in view of the generally accepted theory that the hypostracum arises by direct transformation of the muscle-attachment epiderimis. These hypostracum-pearls shrink, on decalcification, to about one-third of their original diameters (Pl. XX XIX. figs. 22 & 23), When the tissue is old and defectively preserved, as in this preparation and in that shown in fig. 19, they come away from the wall of the enclosing sac during decalcification ; but in better- preserved material, where the connection between the muscle- attachment epithelium and the pearl is maintained, the organic basis of the decalcified hypostracum-pearl remains attached to the wall of the sac (Pl. XXXYV. fig. 8). Nacreous pearls, on the other hand, almost always shrink away from the sac on decalci- fication. The smallest of these hypostracum-pearls that I observed measured about 0°02 mm. in diameter. As the muscle-attachment epithelium, in Margaritifera at any rate, takes at most a very small part in shell-thickening, the size of these hypostracum-pearls is limited by the maximum thickness to which hypostracum normally attains. For further growth to occur, resulting in the formation of a nacreous muscle-pearl, it is necessary for some of the nacre-secreting epidermis to be present also (Pl. XXXYV. figs. 8, s., & 9; Pl. XXXVI. fig. 10, sac.). Fig. 8, from a specimen given to me by Prof. Herdman, shows above a nacreous muscle-pearl and below a hypostracum muscle- pearl. Here we have a cyst, which is more or less spherical, and contains a large central cavity lined with a substance which is indistinguishable from the organic basis of hypostracum. Where an epithelium can be detected in the wal] of the cyst (m.ep.') it possesses all the characters of muscle-attachment epithelium, its cells being continuous with the muscle-fibres, m., on the one hand, and with the hypostracum, hy., on the other. In some cases the muscle-attachment epithelium can be traced on all sides of the sac; in others, as in fig. 8 and fig. 10, ¢., only at certain parts. In still others no such epidermis is recognisable. I think, however, it is safe to assume, whether the hypostracum-pearl is surrounded by a sac of attachment-epidermis or not, that such a ‘pearl can only arise where such a sac is present ; and it is easy to detect the epithelium in most of the better-preserved examples (figs. 8, 9, & 10, m.ep.). Still, in some of the fairly well-preserved preparations I can identify no such epithelium. ‘This is the case in Pl. XXXVI. fig. 11. In this example, which is on one of Prof. Herdman’s slides, the hypostracum-pearl, which measures 21* 324 DR. H. LYSTER JAMESON ON 80 p in diameter, and has a wall about 10 y» thick, lies close to a nacreous muscle-pearl, about 1 mm. in diameter, the sac of which is shown at ep.p.s. The cyst is embedded in a strand of muscle traversing the mantle-parenchyma obliquely, and ending in muscle- attachment epidermis which was attached to the shell. (Such connections between the general musculature of the mantle and the shell occur here and there quite apart from the more regular muscle-scars. For examples of this in Mytilus see List, 27}, Pl. 8. fig. 1.) The cyst contains at one point a little granular mass. The muscle-fibres here appear to be in direct contact with the hypostracum. The easiest explanation of this condition would seem to be the hypothesis that the original epithelium has dis- appeared. It is not difficult to suppose that a highly specialised “¢endinous” epithelium, like the attachment-epidermis, whose fate seems to be to become a part of the shell, is incapable of regenerating itself, and, therefore, destined to die and disappear on ceasing to be functional. If we take this view, the typical hypostracum-pearl is not so much a stage in the development of a nacreous pearl as a phase parallel with it; the latter arising when the original sac contains some of the ordinary nacre-secreting epidermis, or cells capable of giving rise thereto, the former when it is composed of attachment-epithelium alone. The hypostracum- pearl would thus have a limited growth, the nacreous pearl an unlimited growth. However, in considering these cases where there does not appear to be any attachment-epithelinm, it must be remembered that this particular epithelium is often very difficult to see, so that some workers have even failed to detect its existence on the regular muscle-insertions. Much light can no doubt be thrown on these questions by a really thorough study of the behaviour of the cells at the places where the muscle-attachment epithelium goes over into the ordinary epidermis of the mantle, and of the histological phenomena associated with the wandering of the muscle-attachment. The material of the pearl-oyster that [ have examined so far is not sufticiently well preserved to allow of such study. So far as I know, this important matter has never been properly investigated in any mollusc. T will now pass from the hypostracum muscle-pearls to the nacreous muscle-pearls. Typical instances of these are shown in Pl. XXXV. figs. 8 & 9 and Pl. XXXVI. fig. 10. These three examples are all explicable as derivatives of the hypostracum- pearl. Figs. 8 & 10 obviously lie im the borderland between one of the regular muscles and the parenchyma (fig. 8 is at the insertion of one of the pedal levators). Fig. 9, from one of Prof. Herdmaun’s slides, is in a place in the free mantle where a few small muscle-strands (mzsc.) are attached to the shell. ‘The sac of each of these pearls is lined in part by ordinary nacre- secreting epithelium, underlying which is the typical granular parenchyma, in part by muscle-attachment epithelium, continuous with the musculature. As the former is much more active than the latter, these pearls are all eccentric in shape, having a hilum THE CEYLON PEARL-OYSTER. 325 of hypostracum at one side, which, unlike the nacre, does not increase appreciably in thickness. The centre of each is a cavity, which in figs. 8 & 10 is obviously lined with hypostracum, and this hypostracum is connected by a plug of the same substance with the remaining muscle-attachment epithelium. In fig. 9 the growth of the nacre has pulled down the plug of muscle-attachment epithelium into the hilum, and produced quite a long strand of hypostracum-like substance. The presence of these hila, together with the effect of the mutual pressure of muscle-pearls when crowded together, has much to do with the generally irregular shape of commercial seed-pearls. Fig. 10, also from one of Prof. Herdman’s slides, shows a very early stage in such a muscle- pearl, with a small cyst-like hypostracum-pearl alongside it. Here the ordinary epithelium of the sae seems to be gaining on the muscle-attachment epithelium. These muscle-pearls always contain a central cavity, which may be broken up by trabecule of hypostracum-like substance or of conchyolin, this substance being continuous with that forming the lining of the cavity. The cavity, like that of the pure hypostracum-pearl, may be empty or may contain more or less granular matter. Muscle-pearls are often clustered and may be very numerous, Thus the old unlabelled material in the British Museum has dense clusters of these pearls in some places, and so has some of Dr. Kelaart’s material. It is by no means the case that muscle-attachment epithelium always persists in the sac of a muscle-pearl. The whole sac may pass over at an early stage into nacre-secreting epithelium, a process which is, perhaps, analogous to what occurs in the wake of an advancing muscle in the growing shell. This was apparently the case with the pearl that occupied the sac adjoining the body shown on Pl. XXXVI. fig. 11. The nucleus of this pearl is shown at fig. 12 on the same plate. The central portion of this pearl is composed of irregular conchyolin-like substance, which cannot be identified as hypostracum, and which quickly gives place to ordinary nacreous substance (n.). In the neigh- bourhood of this pearl is another, not figured here, the centre of which was comparable to the pearl shown on Pl, XXXV. fig. 8; this pearl had become more spherical secondarily by the dis- appearance, in the course of its growth, of the muscle-attachment epithelium. It is hard to conceive that these two pearls, and the hypostracum-pearl associated with them, are not all of similar origin. Pl. XXXVI. fig. 13 shows the centre of another pearl, perhaps a muscle-pearl, from the mantle-margin, in one of Prof. Herdman’s slides. This pearl appears to have measured about 2 mm. in diameter. The central cavity is about 0°1 mm. in its greatest diameter and is lined by abnormally thick conchyolin-like substance. Outside this are layers of ordinary nacre, which pass over into a form of repair-nacre showing radial markings, € 326 DR. H. LYSTER JAMESON ON probably due to variations in the rate of secretion of the con- stituent substances. This zone is 0°03 mm. thick. The central cavity is empty, except for a few granules. In this case the muscle-pearl, 1f such it is, does not contain a pseudo-nucleus composed of hypostracum or a spherocrystal-like body such as those shown in figs. 19 & 20; and the real “nucleus” of such a pearl might be said to be a cavity which may or may not contain a few indistinct granules, perhaps of foreign origin. The same condition is also typical of those pearls which I have examined from Dr. Kelaart’s material. I have decalcified 58 of these in all (Pl. XXXVI. figs. 14, 15,& 16; Pl. XX XVIII. figs. 17 & 18; Pl. XLIV. figs. 46, 46 a, 47,47 a, & 48). That these pearls are of the same nature as the other muscle-pearls seems probable from the fact that a few hypostracum-pearls occur mixed with the other pearlsin Dr. Kelaart’s specimens, and from the com- plete series of intergradations between the various forms described above, which is shown by the unlabelled specimens in the British Museum, described below. Pl. XX XVII. fig. 14 is a section of Dr. Kelaart’s specimen showing “pearls in ovary.” Hach of these pearls lies in a cavity which doubtiess was originally lined with an epidermal epithelium, though this can no longer be recognised owing to the state of preservation. The cavity is surrounded in every case bya layer of the granular subepidermal parenchyma (par.). Some of the pearls have been forced ont of the subepidermal layer, and now lie embedded in the deeper connective-tissue, in which are seen muscle-bundles and tubules of the ovary. Tn each case the centre of the pearl is a small cavity, containing a few granules or strands of what appears to be conchyolin ; but the pearl in the lower right-hand corner contains also some columnar substance. The irregular conchyolin-like matter is well seen in the centre of the pearl in the top left-hand corner of the sketch, which is shown enlarged in fig. 15. It is interesting to note that the series of sections from which these drawings were made contained an example of the smaller Cestode larva, Z'ylo- cephalum minus. Plate XLIV. figs. 46, 46a, & 47, 47a show two pearls picked from one of Dr. Kelaart’s specimens, decalcified, and examined whole in oil of cloves (46 & 47) and after being sec- tioned (46a & 47a). Fig. 46 shows a dense central mass, of closely laminated nacreous substance, which on _ superficial examination might be taken for the remains of a dead parasite, but a section shows that the whole pearl is composed of nacreous substance around a small central cavity. Fig. 47, examined whole, was extremely suggestive of a dead parasite ; indeed, the concentric lamination of the pseudo-nucleus was not disclosed till sections were cut. ‘These (fig. 47 a), however, furnished the explanation. The real centre of the pearl was, as in the rest of Dr. Kelaart’s material, a nacreous THE CEYLON PEARL-OYSTER,. 327 pearly mass, with a central cavity, showing at one side a plug of conchyolin-like substance. External to the normal central nacre were some irregular layers, such as one gets on the inner surface of the shell when a dark blotch or blister is caused by derange- ment of the secreting epithelium (compare the ‘ Olflecken ” in Margaritana, Rubbel, 34a). The opaque character of these layers, some of which were brown through the immigration or infiltration of what appeared to be cellular matter, others distinctly columnar (repair-substance), rendered the real nature of the pseudo-nucleus obscure till sections were cut. Outside these abnormal and pathological layers typical nacre was sub- sequently produced, thus giving a normal pearl with a dark centre. The same characters are shown on Pl. XLIV. fig. 48, where the centre of the pearl appears opaque and granular for a similar reason. In this case the pseudo-nucleus measured about 5 mm. in diameter, and, examined entire, might have been taken for a dead parasite. It was such a nucleus, coupled with the presence of Trematodes, probably Muttwa margaritijere Shipley & Hornell, in the tissues of Dr. Kelaart’s pearl-oysters, that, in 1901, led me to the probably mistaken conclusion that a Trematode might be one of the organisms which afford the stimulus for the formation of the pearl-sac in MJargaritifera vulgaris, as the Trematode Gymnophallus does in Mytilus * (25, p. 162). But examination of sections (Pl. XXXVII. fig. 16 and Pl. XX XVIII. fig. 17) showed that the opaque pseudo-nucleus was due to a break in the continuity of the nacre; a layer of granular substance (gr.), apparently dead cells (perhaps of the nature of the “oil-spots” in JJargaritana, or derived from an immigration of leucocytes such as Moynier de Villepoix observed (28, p. 112) or from Protozoan parasites), being followed by the secretion of two horny layers of amorphous repair-substance (am., am.'), after which normal nacre resumed its development. The real centre of this pearl, as in the rest of Kelaart’s material, consists (PI. XX XVIII. fig. 18) of shreds of conchyolin-like material, and a few obscure granules, in a cavity which is sur- rounded first by granular repair-nacre and then by ordinary nacre. In the two unlabelled specimens in the British Museum, from which Pls. XXXVIII.-XL. figs. 19-28 and Pl. XLIV. fig. 49 are drawn, while the pearls agree with those described above in their clustered habit, occurrence in the muscular regions, and association with hypostracum-pearls, we have more frequently as nuclei either hypostracum or special sphzrocrystal-like bodies, which I regard as formed of columnar repair-substance. * Fuller knowledge and closer study lead me to doubt the accuracy of my own observations as to the occurrence of the remains of 'rematodes in the pearls produced by the other species of molluscs referred to on p. 162 of my 1902 paper with the exception, of course, of Mytilus edulis, in which the relation between Trematodes and pearls is beyond question. 328 DR. H. LYSTER JAMESON ON Pl. XX XVIII. fig. 19 shows a group of such pearls, scattered among which are hypostracum-pearls (hy.p.). The nucleus of the eccentric pearl at mw.’ is clearly composed, like that of the incipient pearl shown on Pl. XXXIX. fig. 22, nac., of hypo- stracum, and resembles the hypostracum-pearl shown at fig. 21, which has a small quantity of granular contents. One of the columnar nuclei is shown enlarged at fig. 20. This is the nucleus of the large pearl shown in the upper part of fig. 19 (Pl. XXXVIIT.). Centrally there is a small cavity, in which a granular mass of doubtful origin is noticeable (gr.). This cavity is surrounded by an irregular zone of substance which seems to be the same as the amorphous repair-substance of the shell (of. Pl. XL. fig. 29). Externally to this there is columnar substance, forming a sort of spheerocrystal-like mass, the fibro- crystalline calcium carbonate being deposited in a conchyolin-like basis, which, on decalcification of the pearl, remains as a framework. This substance is seen cut tangentially at one end of the pseudo-nucleus. Outside this is the normal nacre of the pearl. In one or two cases the amount of granular matter in the centre of the pearl was considerable ; thus Pl. XL. fig. 24, which is taken from the same series as the preceding figures, shows the central portion of a pearl which has a dumbbell-shaped double nucleus, the larger half being about 17 mm. in diameter, and each half containing an opaque brownish mass of dead animal matter, perhaps of cellular origin, but quite unrecognisable. The contents of the two cavities were continuous at one point. There is nothing to suggest that either of these bodies represented a dead Cestode; I could find no denser portion, such as would naturally occur at the point representing the myzorhynchus, nor was there anything that could be safely identified as the cuticle of the parasite. If the contents suggested anything, it was rather the remains of a large Protozoan parasite, containing spore-like bodies in a plasma (like the Sporozoan spores which Dubois claims to have identified in the nucleus of a pearl from J/. vulgaris from the Mediterranean, 7, p. 311, and 8, p. 104); or, perhaps, a mass of mucus containing a few cells. Hach of these centres was surrounded immediately by the amorphous substance, this being followed by, and continuous with, a radially calcified layer, the bases of the calcareous prisms being evidently embedded in the amorphous substance, which extended up between them to form the organic framework of the columnar substance. This condition is comparable to that seen at tr. on Pl. XLI. fig. 30, which shows the amorphous substance secreted at the junction of two pearls in a compound pearl, passing over into columnar repair- substance. Externally to the columnar layer of the pseudo-nucleus the normal nacreous layers of the pearl are formed, The other extreme is shown on Pl. XL. fig. 25,a hypostracum- pearl ‘08 mm. in diameter, the central cavity of which has no contents whatever. THE CEYLON PEARL-OYSTER. 329 Pl. XL. fig. 26 shows a pearl having for its nucleus a double hypostracum-pearl, the two constituents being apparently separated by a mass of amorphous substance. Other examples were examined which showed intergradations between double and single hypostracum-pearls. In tig. 27, from the same preparation as the above, there is a central cavity, containing a few granules, and surrounded by amorphous and columnar substances followed by nacre and finally by hypostracum. In another case in the same preparation the same state of affairs was shown, but there were further layers of nacre outside the hypostracum, resulting in a fair-sized pearl. These cases are of interest as indicating that the attachment of muscle-fibres to a pearl may arise secondarily, in the course of its growth. Im some cases the columnar substance is stratified, as in the pearl at the bottom left-hand corner of fig. 19, Pl. XX XVIII. andin fig. 49, Pl. XLIV. In Pl. XL. fig. 28, which is the left-hand pseudo-nucleus of the double pearl shown in fig. 49, there is at one pole a distinct transition from the columnar matter of the pseudo-nucleus to normal nacre (nac.'), just as occurs in the substance of the pearls figured at Pl. X LI. fig. 34 and Pl. XLIIT. fig. 43. This pseudo-nucleus is followed by normal nacre (xac.), after which there is a layer of brittle horny matter (am.), which I regard as analogous to amorphous repair- substance ; this is followed by another columnar layer (col.’'), imperfect on one side, and this again by nacre. A preparation from the second unlabelled specimen in the British Museum showed, side by side, all kinds of intergradations between the various kinds of nuclei and pseudo-nuclei of muscle- pearls described above. I regret that I am as yet unable to trace the origin of the muscle-pearls beyond the cyst-like sac, lined with hypostracum or another form of shell-substance. One or two preparations show cavities lined with a few cells, which may represent the first stages of pearl-sacs. Moreover, here and there, the relations of the epidermis, at the place where the muscle-attachment epithelium gives place to ordinary mantle-epithelium, suggest that these cysts arise by direct invagination at this region. What may be the mechanism which gives rise to this invagination I cannot say, there are certain indications that suggest that it may be associated with the presence of parasitic Protozoa, an idea suggested by me in 1902 (25, p. 162); but until I have been able to examine better-preserved material, it would be unwise to hazard yet another theory of pearl-production. At any rate, it is clear that, if pearls in J/. vulgaris are of parasitic origin (and T adhere to the view that the distribution of pearl-producing examples of this and most other molluscs can at present best be explained on the parasitic hypothesis), the immediate cause of the pearl is not the mechanical irritation caused by the body of the parasite, but rather the toxic properties of its secretions, which lead to the pathological changes (formation of the tumours that 330 DR. H. LYSTER JAMESON ON we call pearl-sacs) in the tissues; and that consequently the ‘cause ” of the pearl is not to be looked for in the nucleus, which in the Ceylon pearl-oyster frequently does not exist, but rather im the tissues of the oyster. This is, after all, just what I said at the bottom of p. 142 in my 1902 paper. The characters of muscle-pearls may be summed up as follows :— (1) They usually and probably invariably arise in close associa- tion with the epidermis at the point where muscle-attachment epithelium passes over into normal nacre-secreting epithelium. (2) They frequently occur several together or clustered in numbers. (8) They are typically formed around central cavities in which granules may be, but are not necessarily, present, and which may be lined in the first instance with hypostracum, ordinary nacre, or repair-substances analogous to those which occur where the normal shell-secreting processes are disturbed. (4) They are often associated with great numbers of little bodies, which Herdman calls “ calcospherules,” and which I regard as minute pearls composed of hypostracum. (5) They are, according to Herdman, characteristic of certain of the Ceylon beds; and are, therefore, local in their occurrence, which would give support to a parasitic theory of their origin. B. Parenchyma-Pearls ( Cyst-Pearls,” Herdman). This class contains a much more heterogeneous group of nuclei and pseudo-nuclei than the last. The pearls which it comprises may have arisen from more than one cause, and it is more than likely that a great many of the pearls which I refer to it are, in fact, of the same origin as muscle-pearls, but have been produced singly at spots where two or three muscle-fibres are attached to the shell, instead of in clusters at the regular muscle-insertions, and have consequently assumed a spherical form *. Parenchyma-pearls often show a distinct central nucleus con- sisting of granules or masses of dark substance which might be either of parasitic origin or derived from dead tissue-cells (e. g. leucocytes). In some cases the nuclei of these pearls contain or consist of grains of sand or other foreign particles. The nucleus is typically succeeded by one or more layers of repair- substance, which often intergrades with the normal shell- substances (nacre etc.) of the pearl. In consequence of the presence of this abnormal shell-substance the centre of a paren- chyma-pearl frequently contains a dark, spherical, concentrically laminated, radially striated pseudo-nucleus. This opaque pseudo- nueleus has no doubt on many occasions been mistaken for the remains of a parasite, in pearls decalcified and examined entire ; but seetions generally reveal its real nature unmistakably. * These occasional attachments of small muscles to the shell on the general mantle-surface are well known. See e.g. List (27 0), pl. 8. fig. 1. THE CEYLON PEARL-OYSTER. 331 Cestodes may possibly occur in the centres of these pearls at times, as Professor Herdman maintains, just as grains of sand and other organic and inorganic particles cer tainly do; but this remains to be proved, and my material has afforded no evidence in favour of this much-quoted theory. And, even if it should be proved that Cestodes do occasionally occur as the “ nuclei” of Ceylon pearls, the real causes which underlie the development of the pearl-sac (which is the essential factor in pearl-production) have still to be discovered. The characters of the centres of parenchyma-pearls can best be understood by reference to the next section of the paper, which is largely descriptive of them, pion many of the pearls referred to therein are unquestionably “ muscle- pearls,” (14) Descriptions oF THE CENTRES OF INDIVIDUAL PEaRLs. In the absence of evidence connecting them with muscle- pearls I propose to treat the four pearls from the Persian Gulf, and the twenty-one pearls purchased for me in Ceylon by the Ceylon Company of Pearl Fishers, Ltd., as parenchyma-pearls, and to describe along with them eight of the pearls in Prof. Herdman’s collection of slides which are not obviously muscle- pearls. These descriptions will be followed by an account of a number of samples and collections of pearls from J. vulgaris from Ceylon and other localities. A. Material from the Persian Gulf. It may be useful to begin with the material from the Persian Gulf. ‘This, so far as it has been examined—for some of my specimens still remain unopened,—comprised three pearl-bearing examples, containing four small pearls. All these pearls appeared to be of the kind classified by Prof. Herdman as “ cyst- pearls” and by the present writer as ‘‘ parenchyma-pearls,” as they seem to have arisen quite independently of, and away from, the muscle-insertions. I append a short description of the conditions in each of these cases. Preparation LXIV a contained a solitary pearl, about 2mm. in diameter and slightly lenticular in shape, situate in the left mantle-lobe, on a level with the anterior end of the attachment of the outer gill-lamella. Unfortunately, owing to imperfect penetration in the embedding process, this pearl did not presenti a complete series in section. It lay wholly in the subepidermal parenchyma, which was sharply cut off from the underlying visceral connective-tissue by a layer of musculature, under which were the tubules of the ovary. The pseudo- -nucleus was a radially calcified concentrically laminated body, about 3 mm. in diameter, with a few darkly staining granules in the centre. The second specimen, Preparation LXIV 3, contained another 332, DR. HU. LYSTER JAMESON ON solitary pearl, which before calcification measured somewhat over a millimetre in diameter, but when decalcitied shrunk to ‘7 mm. It was situated in the left side, in the wall of the visceral mass, over the stomach. In section (Pl. XLI. fig. 33) the pearl is seen to le in the subepidermal parenchyma (par. ), projecting a little through the muscular coat (masc.) into the visceral connective- tissue (ext. ), 1 which the tubules of the ovary (ov.) and muscular strands to the wall of the stomach (musc.’) are seen. The pearl. sac has been ruptured, presumably by the evolution of bubbles of carbon dioxide during decalcification. The pseudo-nucleus, which measures about *3 mm. in diameter, consists of several layers of columnar substance (col.) formed around a small central cavity. Probably such a pearl would, as it increased in size, grow through the muscular layer and work its way into the visceral mass; indeed, as soon as more than half its bulk lay on the inner side of the superficial musculature, the action of these muscles would tend to force it into a deeper position, where, relieved from the pressure of the shell, it would stand a better chance of growing into a perfectly spher ical “‘ fine pearl.” Preparation LXIV c, the third of these pearl-bearing examples from the Persian Gulf, contained two pearls, of minute size, about 2mm. apart on the left side. Hach was rather less than 1 mm. in diameter; one was round, the other elongated. Both lay in the subepidermal parenchyma, separated from the ovary by the usual muscular sheath of the visceral mass. Both had pseudo- nuclei of columnar substance. That of the more elongated one is shown in Pl. XLI. fig. 34. It has a central cavity, with irregular granular contents (gr.), surrounded by a number of layers of nacre (nac.), outside which is a complete layer of columnar substance (col.) which is coated on two sides by nacre, passing over at the two poles corresponding to the longest axis of the pearl into further coats of columnar substance (col.'). The transition from nacre to columnar substance is very well seen. The centre of the second pearl in this example was also composed of columnar substance, formed around a central granular mass. The granular mass measured about ‘02 mm. in diameter, the whole centre or pseudo-nucleus °3 mm. These preparations, apart from the difficulty of obtaining material from the Persian Gulf, are of interest as showing that the nuclei or pseudo-nuclei of the pearls produced by J. aul garis in these waters do not differ from those of the pearls produced by the same species in Ceylon. B. Pearls purchased in Ceylon. T will now proceed to a short account of the nuclei and pseudo- nuclei of the tweuty-one pearls purchased in Ceylon. All of these were decalcified, examined entire in oil of cloves, and drawn. Eighteen of them were also sectioned. (The drawings THE CEYLON PEARL-OYSTER. 333 of those not figured here are retained with the slides for reference.) (a) One (Preparation XLV) had no obvious nucleus or pseudo- nucleus. (>) One (Preparation XLITT) had a small spherocrystal-like centre of columnar substance, with no foreign contents (Pl. XLV. figs. 50 & 50a@ and Pl. XLI. fig. 35). (c) Three (Preparations XL, XLIV, & LIV) had what appeared to be irregular masses of amorphous shell-substance, in central cavities, passing over into repair-substance (PI. XLV. figs. 53 & 53a; Pl. XLVI. fig. 57; and Pl. XLII. fig. 40). (2) Three (Preparations XLVIT, LIIT, & LIV c) had central cavities containing more or less granular matter, the character of which could not be determined, but which suggested dead organic particles (Pl. XLV. fig. 52 and Pl. XLII. fig. 36). This was surrounded by repair- substance of columnar structure. (e) One (Preparation LIV 3) had in its central cavity granular matter in which diatoms, fragments of sponge-spicules, (¢) minute sand-particles, and vegetable débris were present. These were surrounded by columnar repair-substance (Pl. X LITT. fig. 44). (f) One (Preparation LIV) had, in the otherwise indis- tinguishable granular contents of the central cavity, a fragment of a Radiolarian shell (Pl. XLII. fig. 45). (7) Four had undoubted sand-grains, forming the nuclei around which the pearl was laid down (Preparations LIT, LIV a, LIVu, & LIVt1). The largest diameters of the sand-grains in these four cases measured, respectively, ‘8 mm. 3x'l5mm., ‘6mm., and ‘3mm. (Pl. XLV. figs. 54 & 54a; Pl. XLVI. figs. 55 & 56). (2) One (Preparation LIV x) had a large spherocrystal-like pseudo-nucleus of repair-substance, intergrading with nacre, and a central cavity which had been partly obliterated in cutting the sections, but apparently con- tained several small quartz-fragments. (t) Six pearls (Preparations XLII, LI, LIVs, LIVp, LIVae, & LIV F) had, in their centres, bodies which were so hard that they broke away in sectioning, and were unfortunately not returned to me with the sections. The probable diameters of these bodies in the first five pearls were respectively ‘45 mm., *2mm., ‘1 mm., -25mm., and ‘6mm. Preparation LIV F had a _ pseudo-nucleus of amorphous substance so dense that it broke away. In the cases of XLIT, LIV, and LIV a, I feel pretty sure that the nuclei here too were grains of sand, the others may have had either sand-grains or abnormally bard amorphous substance in their centres (Pl. XLV. fig. 51 ; Pl. XLII. figs. 37-39). 334 DR. H. LYSTER JAMESON ON Turning now from the “ nuclei” of these pearls to the “ pseudo- nuclei” which surround them, these do not appear to present any characters which cannot be expressed in terms of the several pathological varieties of shell-substance described above. Thus P]. XLII. fig. 44 shows the nucleus (composed of diatoms, etc.) surrounded by typical amorphous and simply columnar repair- substance, followed by ordinary nacre. This appears to be equally the case in Pl. XLVI. fig. 55, where the nucleus is a sand-grain. Pl. XLI. fig. 35 and Pl. XLV. figs. 50 & 50a, which had no foreign nucleus, Pl. XLII. fig. 36, Pl. XLV. fig. 52 with granular contents in a central cavity, and Pl. X LIT. figs. 37-39, in which example the nucleus was a sand-grain, and Pl. XLY. figs. 51 & 53 and Pl. XLVI. fig. 56, show these pseudo-nuclei to be composed of varieties of the columnar substance. Fig. 57 (Pl. XLVI.) and figs. 40-42 (Pls. XLII. & XLII.) show it highly stratified, and presenting every gradation from amorphous to prismatic substance. This preparation is a “ brown pearl,” vather over 3 mm. in diameter, composed of the prismatic shell- substance, and probably produced in the mantle-margin. It consists of an outer zone, clearly identical in characters with the prismatic layer of the shell, and showing three distinct series of prisms. The bases of the innermost layer of prisms are shown in fig. 42, pr. Inside this normal prismatic substance is the “ pseudo- nucleus,” which consists externally of a layer resembling in every respect, except the diameters of its constituent elements, the prismatic layers (figs. 41, 42, col.). Internally this passes over, through a substance resembling irregular columnar repair-substance (fig. 41, ¢.), into amorphous substance containing columns or scattered depositions of carbonate of lime (figs. 40, 41,a@m.). In places these bodies are ranged in radial rows, and the amorphous substance nearly reaches a stage which could be called columnar substance. Just around the centre (fig. 40, col.) typical columnar substance occurs, passing over internally into amorphous substance. Owing to the impenetrability of the amorphous substance, the ealeium carbonate has not been dissolved in the deeper layers of the pseudo-nucleus, and it is seen in the nucleus itself to occur in the form of perfect rhombohedra, a form J have never seen it take on in the alveoli of the normal or abnormal shell-substance. The resemblance of this pearl to the brown Scotch river-pearls (e. g. that figured by me in ‘ Nature’ for Jan. 22nd, 1903, p. 281 [26]) is striking. Preparation XLITI, from which figures 50 & 50a o0n Pl. XLV. and fig. 35 on Pl. XLI. are drawn, showed an oval central body, about °6 mm. long, forming a “ pseudo-nucleus.” On superficial examination this nucleus is highly suggestive of a Trematode (fig. 50). But sections showed it to consist of a small sphero- crystal-like body (fig. 85) about ‘08 mm, in diameter, surrounded by granular repair-nacre. THE CEYLON PEARL-OYSTER, 335 Figure 51 shows a pearl, the ‘‘ pseudo-nucleus” of which is produced out in one direction as a strand of columnar and granular repair-substance extending through the pearl. This column: ar substance is seen to pass over laterally into the ordinary nacre, and no doubt corresponds to an area in the pearl-sac at which the normal secretion-processes were disturbed. ‘This was one of the examples in which the real nucleus broke away. Fig. 36 on Pl. XLIL., which is the centre of the pearl shown in fig. 52 (Pl. XLV.), enlarged, shows interesting transitional substance at one pole. This is further enlarged at fig. 43, Pl. XLII. The pseudo-nucleus is seen to be discontinuous with the later-deposited shell-substance, a condition of things which is sometimes found, and which seems to suggest a pause before the epithelium becomes properly functional. Plate XLV. figs. 53 & 53a show a pearl with a spherocrystal- like pseudo-nucleus, the longest diameter of which slightly exceeded 1mm. In this case the columnar substance was very minutely reticulated and fell into three distinct zones. The pearl is interesting, as showing at one side a patch of columnar repair-substance apparently continuous with the nacreous layers, secreted over some foreign matter (granules) that had found their way into the pearl-sac during the course of the pearl’s growth ; this columnar substance formed a small “ blister” in the substance of the pearl. Where a sand-grain is present as nucleus, it appears to be followed, as a rule, by repair-substance ; but in Pl. XLV. fig. 54 this is hardly discer nible, except at one pole. This was a pearl which was drawn entire, and sent to be sectioned, when it was found that the nucleus broke away and resisted cutting. This nucleus was returned to me, and proved to bea siliceous sand- grain (fig. 54a), measuring about °8mm. in diameter. It was surrounded by an opaque substance, probably “ amorphous repair- substance.” Fig. 56 (Pl. XLVI.) shows a sand-grain which measured about *35 x ‘25 mm. surrounded first by amorphous substance, then by stratified columnar substance. Fig. 55 (Pl. XLVI.), taken from a pearl which I have preserved entire, shows a pyriform sand-grain, ‘66 x ‘5 mm., surrounded by a thin layer of columnar substance, followed by nacre. Figs. 37-39 (Pl. XLII.) are from the capsule surrounding a nucleus which broke away and was probably a sand-grain. Here, again, we have first the amorphous substance, passing over into “ columnar” substance of sphzerocrystal-like for m, with regular alveoli, which are approximately equal in length, breadth, and depth. Vigures illustrating minor varieties of the repair-substance as it occurs in the shell, in the pearl, and in the pearl pseudo-nucleus might be multiplied indefinitely, but I think enough have heen given to illustrate my contention that these dark spherical bodies, 336 DR. H. LYSTER JAMESON ON which so often suggest parasites, are usually in the Ceylon Pearl- Oyster pseudo-nuclei of spherocrystal-like structure, each of which is reducible to a certain amount of amorphous non- calcified matter forming the lning of the nuclear cavity (figs. 35, 36, 37, 40, 41, & 44, am.), and the same substance, some- times stratified, sometimes not stratified, containing depositions of calcium carbonate. It may be necessary to differentiate these pseudo-nuclei into two groups, typically represented by figs. 36 and 40-42 respectively—the one secreted in all probability before the epithelium of the sac could control its deposition at all (and thus comparable to a “ Harting’s Body”); the other secreted by an already partly functional epithelium. When material with pearls in various stages of formation a sitw in the tissues is available, this distinetion may prove to have an important relation to the actual processes by which the pearl-sac arises, and to the difference between the nuclei of muscle-pearls and some parenchyma-pearls. The most remarkable thing about this lot of pearls purchased in Ceylon is the high percentage which have as nuclei grains of sand or other foreign bodies. These cases might certainly be held to give support to the old theory that the stimulation of any in- trusive particle, 1f it occurs at the right place, may give rise to a proliferation of epidermis resulting in the formation of a pearl-sac and a pearl. But, on the other hand, evidence is not lacking that the matter is by no means so simple as this. I am instituting some experiments on Mytilus (in connection with investigations on the life-history of the pearl-inducing Trematode that I am carrying on with the aid of a Gover nment Grant) which will, I hope, throw some light on this question. It is idle to speculate, without experiments on living molluses, whether these particles enter the tissue (@) in connection with mechanical i injuries to the shell, as Herdman suggests, or (6) from the intestine, by perfora- tion of the wall, and escape of such bodies as are seen in figs. 44 & 45 (Pl. XLIII.) into the blood, or (c) through lesions of parasitic origin. With regard to the last-named figures, it is interesting to note that so long ago as 1857 Kelaart (277) suggested that the : siliceous skeletons of diatoms might become the nuclei of pearls. 3 C. Professor Herdman’s Slides. Professor Herdman’s preparations, illustrating pearls, which he very kindly lent me, consisted (omitting a few preparations of clustered hypostracum-pearls) of 24 slides, showing about 25 pearls in section. Of these pearls 13, representing 7 preparations, were obviously muscle-pearls, some of which are shown in figs. 9— 12(Pls. XXXV.& XXXVI.). In four of these preparations the cyst-like hypostracum-pearls were also present. Eight pearls which were not obviously muscle-pearls, repre- senting six preparations, are briefly described below. (a) A pearl described in the label of slide as a “ muscle-pearl.” THE CEYLON PEARL-OYSTER. 337 It was about 1°3mm. in diameter, and situated in the body- parenchyma over the ovary (as in the Persian Gulf examples described above). The centre was a mass of concentrically laminated columnar substance, passing over externally into nacre ‘and about 0°5 mm. in diameter. I treat it here provisionally as a parenchyma-pearl, as there is nothing to Suggest that it is a muscle-pearl. (6) This was a nice little spherical pearl, well out in the mantle. The centre was a spherocrystal-like body, of the same nature as those shown in figs. 35 & 36 (Pls. XLI. & XLI [.). There were no recognisable foreign contents, (c) This showed a pearl in the parenchyma over the ovary, as in the Persian Gulf specimens, with, apparently, all the characters of a “ fine pearl.” It had a large dark pseudo-nucleus, 0-4 mm. in diameter, much like that shown on Pl. XLVI. fig.57. There was a central cavity, 0°025 mm. in diameter, containing a small granular mass; this was followed by nacre, then stratified columnar substance, then nacre again. (¢) Showed two pieces of free mantle, sectioned, one with one and one with two pearls in situ. In the case of the former the pseudo-nucleus was incomplete, but could be seen to be composed, in part at least, of columnar repair-substance. In the other specimen, both pearls had centres resemblin g those in Dr. Kelaart’s material, and may well have been muscle-pearls, (e) The central part of this pearl is shown on Pl]. XXXVI. fig..13, The pearl is quite close to the mantle-margin, in the musculature. In the centre there is a eavity with a few granular contents. This is surrounded by what appears to be ordinary naere, then nacre with radial reinforcements, then nacre again. It suggests a muscle-pearl rather than a parenchyma-pear. (7) Contained a pearl, near the mantle-margin, the pseudo- nucleus of which was not complete. It consisted of alveolar- columnar matter; its centre could not be made out. This preparation also contained an example of Z'ylocephalum minus. The remainder of the pearls in Prof. Herdman’s collection, four in number, appeared to be incomplete preparations, as no nuclei or pseudo-nuclei could be observed. D. Unlabelled Pearls (dry) in the British Museum. In September 1911 Mr. E. A. Smith, 1.8.0., allowed me to examine four dry pearls, from a small collection of pearls and attached pearls and blisters, preserved in the Mollusca cabinets at the British Museum. These specimens were unlabelled and without history, but their general characters (colour ete.) were those of If. vulgaris, and the fragments of shell to which some of them were attached were undoubtedly referable to this species, and probably to examples from Ceylon (heavily incrusted and much corroded with Cliona). Proc. Zoou, Soc.—1912, No, XXTI, 22 338 DR. H. LYSTER JAMESON ON Three of these pearls were decalcified, and one of them, Preparation LXXXVI 4, was also sectioned. All showed centres of the same class as those of the pearls in Dr. Kelaart’s collection—that is to say, central cavities containing irregular conchyolin-like strands and a few granules. Two of these pearls were fair spherical pearls, about 3mm. in diameter, which would have ranked as ‘fine’ pearls or ‘ cyst-pearls,” but for blemished surfaces. The third was a multiple pearl, secondar ily attached te the shell, and showed, by the presence of distinct traces of hypostracum in its substance, that it had arisen in a muscular part. KE. Collection of Pearls given to me by Mr. Max Mayer. In April 1911, Mr. Max Mayer, of Hatton Garden, London, and Paris, dealer in precious stones, most generously gaye me for the purposes of my work a number of pearls, mostly of the baroque and seed class (though some could better be de- scribed as pearls that would have ranked as small “ fine” pearls, but for defects of shape, colour, or surface). These included a sample which, after eliminating a number of pearls that, from their colour and other qualities, Mr. Mayer considered were derived respectively from Australia and Panama (these will be dealt with in another paper), left a mixed lot of 115 pearls, most of which showed more or less of the characteristic and indescribable creamy colour which is distinctive of the pearls of Margaritifera vulgaris. Mr. Mayer had no hesitation in saying that the majority of these were almost certainly Ceylon pearls, though he emphasized the fact that it is not often that pearls reach the European markets accompanied by “ certificates of birth,” and that the sources of these specimens could only be judged from their respective characters. These 115 pearls were decalcified and eight of them were sectioned, and several others were dissected to expose the nature of the “nucleus” or pseudo-nucleus. Of this collection not one had a nucleus that could be identified as a Cestode, or indeed as any parasitic worm. Sixty of them had spherocrystal-like pseudo-nuclei composed of columnar repair- substance, sometimes simple, sometimes stratified, sometimes interstratified with other repair- -substances. In some cases a few granules could be detected in the centre, in others nothing of the kind could be made out. These pseudo- nuclei were generally less transparent than the residue of the pearl, often almost opaque but in every case their nature was obvious. Forty-two ‘pearls were of the kind described from Dr. Kelaart’s specimens in the British Museum, ze. they had either no obvious nuclei or their centres contained cavities in which were a few strands of conchyolin-like substance. Six others were of the same class, but contained some refractive granular matter. One double pearl showed a columnar pseudo-nucleus in one constituent and a centre of the “ Kelaart” type in the other, while another, THE CEYLON PEARL-OYSTER. 339 a quadruple pearl, showed nuclei transitional between these two types. There remain the eight examples which had to be sectioned to disclose the nature of their centres, owing to opaqueness. The first, Preparation XCIIJ, had a dark pseudo-nucleus which proved to be composed of stratified amorphous substance, in fact, a sort of horny pearl or periostracum-pearl. It was too hard to section properly, and its real nature was discovered only by dissection of the pseudo-nucleus. Preparation XCIV was a triple pearl, and contained pseudo-nuclei of three kinds, a ‘“* Kelaart” pseudo-nucleus, one composed of columnar substance, and one composed of concentrically stratified amorphous substance. Preparation XCV had an irregular dark nucleus which in seetion proved also to consist of stratified repair-substance, interstratified with granules. In Preparation XCVI the centre was a hard mass of columnar substance, coutaining a body that broke away and may have been either amorphous substanee or a hard body of foreign origin. Preparation XCVII contained a typical columnar body, masked by a thick outer coat of amorphous substance. The remaining three had pseudo-nuelei of ordinary columnar substance. I cannot say whether any of the above pearls contained minute quartz-grains or other foreign inorganic bodies, as this cannot be determined, even with the aid of polarised light, in a great many eases, until sections are cut, owing to the high degree of double refraction possessed by the conchyolin, and the distortion of its original arrangement in the decalcifying process. But such foreign bodies were detected in two pearls given to me at the same time by Mr, Mayer, which were, however, more probably from Margaritifera margaritifera var. mazatlanica (Panama Shell) than from JZ, vulgaris. F. Collection of Ceylon Pearls given to me by Mr, H. Hopkins. In October last Mr. E. Hopkins, dealer in precious stones, of Hatton Garden, kindly gave me a parcel of fifteen small pearls, which he believed to be Ceylon Pearls. He wrote me (letter of 26th October, 1911): “The pearls were obtained from a dealer whose son visited the Ceylon Fisheries on the last occasion when they were open, and from what he has told me I have every reason to believe that these were part of the goods which he brought back.” These fifteen pearls were decalcified and examined as transparent objects, and four of them, which could not be satisfactorily made out otherwise, were subsequently sectioned. Most of these pearls were of the “ muscle-pearl” class, small and angular, but two or perhaps three, both from their more spherical shape and different nuclei or pseudo-nuclei, may more properly be treated as parenchyma-pearls. ‘Twelve of these pearls had centres of the kind characteristic of 22* 340 . DR. H. LYSTER JAMESON ON ‘the pearls in Dr. Kelaart’s specimens, described above, 7.e. had no obvious nuclei, but simply central cavities containing either a few irregular strands of conchyolin-lke substance or obscure granules. Two out of these twelve were sectioned. One, Preparation Text-fig. 41. A. Centre of a Ceylon pearl given to me by Mr. E. Hopkins. Decalcified and examined whole in oil of cloves. Examined thus the body might be taken for the remains of a Platyhelminthian parasite. B. The same in section. The body is seen to be a “ pseudo-nucleus” consisting in great part of amorphous substance, am., along with which is some granular matter, gr. In the centre are some strange spore-like bodies, «, of doubtful origin (Preparation LXXXV 1). X 400. THE CEYLON PEARL-OYSTER. 341 LXXXV 4, had its central cavity lined with hypostracum, as in the pearls described from the unlabelled specimens in the British Museum. The other had a central cavity lined on one side by « hilum-like plug of hypostracum, giving the pearl a reniform outline, and on the opposite side by columnar substance, going over into nacre, ‘wo of these muscle-pearls were composed of several fused units. There remain three pearls which have some claims to be treated as parenchyma-pearls. One of these, which was not sectioned, had in its centre a string of brownish granular matter, *66 mm. long by ‘17 mm. wide, of doubtful origin (Preparation LXXXV 0). Another (text-figure 41, A & B, Preparation LXXXV L) had a pseudo-nucleus +1 mm. in diameter, which, examined entire, might have been taken for the remains of a minute Platy- helminthian parasite, but which on section proved to be made up in great part of amorphous repair-substance. Finally, one pearl (Preparation LXXXV x), a round pearl just under 2 mm. in diameter, possessing apparently all the external qualities of a parenchyma-pearl, had for its centre a pseudo-nucleus of stratified columnar substance, 1 mm. in diameter, surrounding a sand-grain *35 mm. in diameter. G. Pearls from Margaritifera vulgaris from the Gulf of Kutch. Being for the moment unable to obtain freshly preserved material from Ceylon or Madras, I endeavoured to obtain examples of the same species, preserved with pearls im situ, from Northern India, and through the courtesy of His Highness the Jam Saheb of Nawanagar, better known to most people in this country as Prince Ranjitsinhji, I was supplied in October last with a valuable collection of preserved oysters, containing pearls, from the Nawanagar fishery. I wish here to record my indebtedness to His Highness, and to Mr. Merwanji Pestonji, Dewan of Nawanagar, for their help. My thanks are also due to Dr. G, A. Grierson, C.1.E., Director of the Linguistic Survey of India, and to Mr. R. E. Enthoven, I.C.S., for putting me in communication with the Authorities of the State. The detailed histological examination of this material will take some time, but I have decalcified and sectioned a number of pearls, free and iv situ, for purposes of comparison with the material from other sources. As the Nawanagar fishery is little known to biologists, the following information, supplied to me by the Dewan, may be of interest. The fishery, which belongs to H.H. the Jam Saheb, is carried on on the southern shore of the Gulf of Kutch, during the South- West Monsoon season, from June onwards. The ground on which the pearl-oyster is found is * usually the sloping bank of a reef, facing east or south-east, consisting of shingly sand and small 342 DR. H. LYSTER JAMESON ON rocks and stones, clear of all mud.” Mr. Pestonji says that the bottom of the sea around the reefs is muddy, and that it is believed that the heavy rains and seas wash away the mud from the Oyster-beds, and so make it easier to see and collect the oysters. “‘ At high tide there is usually about ten to twelve feet of water over the Oysters. The oyster-beds are never dry, even at low water, there always being an inch or two of water draining off ” *. The fishery is carried on ky wading, at low tide. ‘ During the Monsoon season four or five hundred men are sent out toa certain reef, where they tramp about and pick up the oysters as they come upon them. They stay three or four days on each reef, and when one reef has been searched they move on to another. Hach man is rewarded according to the number and nature of the pearls found in the oysters he brings in.” The oysters are not “rotted,” as in the ease of the Ceylon pearl- fisheries, but are opened one by one, and the pearls removed “ by scraping the flesh gently with a blade of a knife.” The number of oysters fished annually is about 150,000, on an average. ‘he value is uncertain. The number of pearls extracted from these oysters comes to about 20,000 and over. They vary in size from seed-pearls to those weighing 20 grainsand over. The lustre and colour are of first-class order, but the shape in over 60 per cent. of the pearls is poor. Mr. Pestonji estimates that if care is taken to pick up oysters which are about four years old, about 10 to 15 per cent. of them contain pearls. He says, in a letter dated November 14th, 1911: “‘ Lately we opened oysters three times. The first time we opened 643 oysters and got 452 pearls. The second time we opened 770 oysters, and got 537 pearls. The third time we opened 845 oysters, and got only 379 pearls.” Mr. Pestonji includes the minute “ dust ” pearls as well as pearls of different sizes and shapes in this statement, and explains that there are often as many as fifteen or more minute pearls in a single oyster. Highteen pearls from this collection have so far been decalcified and examined, and thirteen of these have been sectioned. Some of these were sectioned 77 szdw in the tissues, others were pearls which had fallen out of the tissues in the preserving process. They differed in no recognisable microscopic features from the pearls produced by the same species in Ceylon and the Persian Gulf. Thirteen of these pearls, six of which were from one specimen and three from another, were of the same character as those described from Dr. Kelaart’s material in the British Museum, that is to say, they had a small central cavity, surrounded by ordinary nacre. The remainder had more or less obvious pseudo-nuclei, composed of columnar or alveolar substance, in some cases intérstratified with nacre. Two of these (Preparations N. VIII. and N. 1X.) had naere inside the columnar substance, with * Spring tides rise 18 ft., and neaps 14 ft., at Rojhi, an island near the town of Nawanagar, according to the Admiralty Sailing Directions, “West coast of Hindustan Pilot ” (1898 edition). THE CEYLON PEARL-OYSTER. 343 a central cavity, and their difference from the “ Kelaart” class of pearls was therefore probably due to a difference in their secondary growth, rather than in their primary origin. One of those sectioned (Preparation N. IV.) had a pseudo-nucleus composed of stratified columnar substance, with internally some nacre sur- rounding a small mass of brownish granules. It cannot, I think, be argued in comparing these pearls with Ceylon pearls that they are all seed-pearls or ‘“ muscle-pearls.” They occurred in all the usual parts of the external body-wall and mantle, and some of them. had all the properties of small “ fine pearls.” Preparation N. VI., for example, was a beautiful little spherical pearl, of high quality, measuring about 2°5 mm. in diameter, which I was extremely reluctant to sacrifice in the interests of science, and a number of the others were solitary * parenchyma-pearls ” of small size. H. Z'wo Pearls from Margaritifera vulgaris from the Mediterranean, given to me by Professor Raphael Dubois. Professor Raphael Dubois most generously placed at my disposal for comparison two small pearls taken from J/. vulgaris from the coast of Tunis. This species has firmly established itself in several parts of the Mediterranean, since the opening of the Suez Canal, having no doubt come thr ough from the Red Sea, either in the free-swimming larval stage or as young spat att ached to the bottoms of vessels. I can add nothing to what Dr. Dubois has already said about the structure of these pearls, (8) pp. 103-— 105. One contained a central body, rather less than *5 mm. in diameter, which on being sectioned proved to be composed of very homogeneous granular matter surrounded on one side by columnar substance and on the other side by “‘amorphous substance.” The other contained a small yellowish spherical body, ‘08 mm. in diameter, which, examined in oil of cloves, showed no recognisable structure. In section it appeared to consist of a very small amount of granular matter, surrounded by what looked like stratified amorphous repair-substance. Dr. Dubois’s observations have shown, without doubt, that the pearls produced by this species in the Mediterranean (and their single occurrence, in positions away from the muscle-insertions, renders it necessary to treat them in part at least as Parenchyma-pearls and not as Muscle-pearls) have not Cestodes in their centres, but have nuclei and pseudo-nuclei similar to those which I have described above, for pearls from the same species from other localities. I. Pearls from M. vulgaris from New Caledonig, given to me by Professor Seurat. Professor L. G. Seurat, at my request, very kindly sent me four small seed-pearls from Margaritifera vulgaris, from New Caledonia, and also a slide, showing a larger pearl from the same species S44 DR. H. LYSTER JAMESON ON decalcified 2nd mounted entire in Canada Balsam. In none of these could I find Cestode nuclei. The example mounted as a slide was a pearl about 2 mm. in diameter, of oval shape, from the Isle of Pines. It had two pseudo-nuclei, side by side, both composed of columnar substance, coneentrically laminated. One measured ‘0 mm., the other ‘3mm. This pearl was subsequently sectioned, and no foreign matter could be detected in the nuclei. I decalcified and examined the other four pearls. The characters of three of them were nearest to those of the pearls in Dr. Kelaart’s collection in the British Museum described above, but one had several centres, which were surrounded by columnar substance. The fourth had a little brown body about -2 mm. in diameter, which sections showed to be composed of unrecognisable granular matter surrounded byamorphous substance. No Cestode characters could be identified in it. M. Seurat also sent me five slides, with sections of pearls from M. vulgaris from New Caledonia, which had been mounted in parafiin wax, but had not been stained or made into finished preparations. I stained and completed these, and found that they comprised about seven pearls, in all of which, so far as could be determined (for the series were not complete), the pseudo-nuclei were either simple cavities containing a few granules or strands of conchyolin- like matter, or masses of concentrically deposited, stratified columnar substance. There was no trace of anything that I could accept as a Cestode. M. Seurat stated (37), p. 24, that these pearls had for nuclei Cestode Jarve, but I am unable to confirm this., In a recent letter he has informed me that this assertion was based on the appearance of the nucleus of a decalcified pearl, which was not, apparently, examined in section. J. Pearl from M. vulgaris from Nossi-bé, Madagascar. M. Seurat also sent me an unmounted slide with sections of a pearl from this species from Nossi-Bé. The centre of this pearl was a mass of concentrically deposited columnar substance, 0:35 mm. in diameter, containing a cavity about 0°l mm. in diameter. K. Pearls from the Lapi Shell (M. vulgaris), from the Trobriand Islands, Papua. Prof. W. R. Dunstan, F.R.S., Director of the Imperial Institute, very kindly allowed me to decalcify and examine two pearls from this locality, which were taken from among those on exhibit in the Papua Court at the Imperial Institute. These specimens had recently been sent home, by direction of the Administrator, the Hon. M. Staniforth Smith. The pearl-banks occur on the western side of Kiriwina Island, THE CEYLON PEARL-OYSTER. 345 and the fishery is carried on by the natives from whom the pearls are bought by licensed traders. The annual yield is between £3000 and £4500 worth of pearls, as valued locally. The first of the two pearls examined was decalcified by me, but was not sectioned. he centre was a double pseudo-nucleus, slightly over a millimetre in length, and a little under a millimetre in breadth. It was obviously composed of stratified columnar substance. External to this the pearl, which was quite a good one, was composed of normal nacre. The second example was decalcified and examined entire, and then sectioned. The centre was a_ spherical pseudo-nucleus, rather less than half a millimetre in diameter, also composed of stratified columnar substance, with a minute central cavity, about 0-02 mm. in diameter. These were certainly not “ Muscle” pearls, but small “fine” pearls. The preparations have been returned to the Imperial Institute. L. Pearls from Placuna placenta, from Lake Tampalakamam, Ceylon. In view of Mr. Hornell’s statement, referred to in the account of the work in Ceylon, to the effect that he had determined that a Cestode larva, similar to or identical with that found in the pearl- oyster, caused the pearls produced in such quantities by Placuna placenta, the Window-pane Oyster, I thought that a study of this form would throw light on the problem in J/. vulgaris. I made several fruitless efforts to obtain material from Ceylonandelsewhere. I examined one small pearl, decalcified and mounted whole, in Professor Herdman’s collection (No. 78), labelled “ Pearl Shelled from Mantle of Placuna.” This pearl measures about half a millimetre in diameter, and the “nucleus” is a little yellowish body, about ‘05 mm. in diameter, and thus too small to be Hornell’s larva (which is said to be from -2 to +4 mm. in diameter), even if it is of foreign origin. However, it was necessary to have material to section before the matter could be investigated. As I could not get other material Professor Dunstan very kindly allowed me to take a few Placuna pearls from the collection on exhibit in the Ceylon Court at the Imperial Institute. Two very well marked size-groups occur in the pearls in this collection, there being a majority of minute irregular pearls, 1 mm. in diameter and under, and a minority of larger ones, averaging from 2 to 3 mm. in diameter. Prof. Dunstan allowed me to take four of the latter and sixteen of the former. All these were decalcified, and two of the larger and four of the smaller were sectioned. Of the larger pearls, Preparation CXLVI (sectioned) had for its centre a cavity, ‘05 mm. in diameter, containing a little irregular columnar repair-substance. Preparation CXLVIT had a central cavity containing a small amount of yellow refractive 346 DR. H. LYSTER JAMESON ON granular matter. The remaining two, which were decalcified but not sectioned, had no obvious nuclei, the centres being, apparently, like those of CXLVI and CXLVII. Of the sixteen minute pearls four were sectioned. Preparation CXXXV had in its centre a simple cavity, like the pearls in Dr. Kelaart’s material of A. vulgaris. Preparation CX X XVI showed a central cavity, with around it some columnar substance, or perhaps hypostracum. Preparation CXXXVII had a large dark pseudo-nucleus, over half a millimetre long, which might easily have been taken for a foreign body, when examined entire, but which on being sectioned proved to be composed of concentrically laminated amorphous substance, passing over in places into columnar repair-substance, and containing a minute central cavity. Preparation CX XX VIII had in its centre a little brown body, probably composed of amorphous substance, but this specimen did not prove satisfactory on being sectioned. The twelve remaining pearls were decalcified and examined entire in oil of cloves, but were not sectioned. Of these four had either a small central cavity, surrounded by ordinary nacreous conchyolin, or no obvious nucleus or pseudo- nucleus. Six had such cavities, partly or entirely surrounded by repair substances or hypostracum, one had a few yellowish granules in its cavity, and one had a dark body, about *3 mm. in diameter, of doubtful nature, but showing no characters that would warrant its identification as a Cestode. The absence of evidence in support of Mr. Hornell’s Cestode theory of the origin of Placuna Pearls is an additional argument in favour of the opinion that the supposed observation of these worms by Mr. Hornell and Professor Herdman in the pearls of M. vulgaris was a mistake. M. Pearls from Margaritifera margaritifera var. cumingi Heeve (the Black-edged Mother-of-Pearl Oyster), from vrkitea, Gambier Archipelago. In order to enable me to compare the pearls of M. vulgaris with those of this species, in which Seurat claims that Cestodes occur as nuclei, M. Seurat most generously placed at my disposal some material. This consisted of three slides on which sections of pearls from this species had been mounted, but which had not been stained or completed. J stained and finished these three slides. In two of them the centre of the pearl could not be found, in the third there was not a section through the exact centre, but there was one that cannot have been far from it. This showed no Cestode remains, but a pseudo-nucleus rather less than half a millimetre in diameter, consisting in its more central part of concentrically deposited columnar repair-substance, passing over peripherally into alternate layers of amorphous and columnar substance, which in their turn passed over into nacre, through catenulated and granular transitional substance, such as I have described in MM. vulgaris. THE CEYLON PEARL-OYSTER. 347 M. Seurat also gave me a piece of the latero-dorsal region of the body of this species, with pearls in situ. This I decalcified and examined in oil of cloves, and afterwards sent to be sectioned. At the time of correcting proof the sections had not been returned. Examined entire in oil of cloves this specimen showed a cluster of about ten pearls. Most of these were like those described from Dr. Kelaart’s material of M. vulgaris, i. e., they had no obvious nuclei; one, however, had in its centre a minute hypostracum pearl or columnar pseudo-nucleus, about ‘1 mm, in diameter ; one had a tiny refractive body, about ‘03 mm. in diameter, which may have been composed of amorphous substance ; and one had some more opaque matter which, however, contained nothing that could be identified as a Cestode. It would seem possible, in view of these observations, that M. Seurat may also have been led into the error of arguing that because the Trematode which is associated with pearls in Mytilus furnishes the stimulation necessary for pearl production, therefore the Cestode in Margaritifera plays thesame role. I hope shortly to receive further material from the French Pacific that will enable me to go into this question more fully. I may add that my studies on pearls from M. mawina, and from the other varieties of I. margaritifera from other localities, so far as these studies have gone up to the present, afford no evidence of the occurrence of Cestodes in the centres of pearls. (15) GENERAL SuMMARY. The following are the principal conclusions to which these investigations have led me :— (1) The evidence that the globular Cestode larve, which Prof. Herdman regards as the cause of the formation of * fine pearls” in the Ceylon Pearl-Oyster, are a young stage of the worm described by Shipley and Hornell as Tetrarhynchus wnionifactor is quite inconclusive. I consider these worms to be more probably referable to the genus 7ylocephalwm (or an allied form), and have provisionally described them under the name of Tylocephalum ludificans and 7’. minus, spp. nn. (2) The theory that these Tapeworms are the cause or a cause of the formation of pearls in the Ceylon Pearl-Oyster (in the sense in which the Trematode is the “cause” of pearls in Mytilus, where the pearl-sac is normally formed as a result of the specific stimulation of the worm) is supported by quite insufficient evidence, and even their occasional occurrence in the nuclei of Ceylon pearls has yet to be demonstrated *. * Sir West Ridgeway, formerly Governor of Ceylon, Chairman of Directors of the Ceylon Company of Pearl Fishers, Ltd., in reply to a question put at the annual meeting of Shareholders in 1909 (reprinted in the ‘ Financial News > on December 21st, 1909), as to what was known with regard to the real cause and mechanism of pearl-formation, implied that the Directors were in possession of valuable informa- tion, of a secret nature, on the subject. “It was most undesirable at this moment that they [i. e. the Directors] should reveal the progress which had been made by 348 DR. H. LYSLTER JAMESON ON It appears, in fact, as though the simultaneous presence of pearls and Cestodes in the Ceylon Pearl-Oyster were a case of two parallel diseases, comparable to the case of a dog infected simultaneously with tapeworms and mange, or of a man suffering at the same time from echinococci and scabies. And even should it be found that tapeworms do sometimes form the nuclei of Ceylon pearls, an explanation of the reason why this occurs in some cases only is necessary. It is, of course, possible that in certain of the Ceylon banks conditions may exist which cause Tylocephalum ludificans to depart from its normal habit, and acquire an ectodermal instead of a fibrous cyst; or it might even be found that in certain banks another species of Tylocephalum (or other Cestode) occurs which, like the Trematode in Wytilus, normally and habitually gives rise to a pearl-sac in the tissues, and which has been confused with Tylocephalum ludificans. But, in any case, pearls formed around tapeworms, if such ever occur (and this still remains to be demon- strated), must be so comparatively scarce that, from the economic standpoint, the réle of the tapeworm in pearl-production in Margaritifera vulgaris must be unimportant. Examination of such pearls from Placuna placenta and Margaritifera margaritifera var. cumingit as were obtainable failed to confirm the supposed occurrence of Cestodes as their nuclei. (3) The shell of Margaritifera comprises in addition to the hinge-ligament the same layers as those of other typical Lamelli- branchs, viz. a periostracum (the outermost layer of which 1s secreted in a different manner to the remainder and is very much reduced in Margaritifera), prismatic substance, nacre, and hypostracum or muscle-attachment substance. In addition to these, certain pathological varieties of shell- substance arise when the normal rhythm of secretion is disturbed, the chief of which are described as amorphous repair-substance (which is probably simply uncaicified conchyolin), columnar repair- substance, and granular repair-nacre. These substances intergrade with normal nacre and prismatic substance, and with each other. The peculiar characters of these substances are the chief cause of the distinctive appearance of the ‘‘ pseudo-nuclei” of pearls. The shell-substance, except the hypostracum and the outer layer of the. periostracum (and probably the ligament), is secreted in liquid form, and its structure and variation may be interpreted as the expression of the normal processes of the crystallisation of CaCO, in a colloidal medium, modified by the periodicity of the action of the shell-secreting tissues of the mantle. (4) The “Calcospherules,” which Herdman identifies as the nuclei of muscle-pearls, are not free concretions or ‘‘ depositions Mr. Southwell in his researches on this question; but he thought that gentleman would support him in saying that those researches had not been unsuccessful up to the present, and promised to be most interesting as well as satisfactory.” Mr. Southwell’s thoroughly frank statements of the case in his subsequent publications do not appear to me to reveal anything sufficiently epoch-making, from the com- mercial standpoint, to render such mystery necessary ! ‘THE CEYLON PEARL-OYSTER. 349 from the blood” (Southwell), but are minute pearls formed of the hypostracum or muscle-attachment substance. They are therefore not the cause of the nacreous muscle-pearls, but a phase parallel to them. There is some reason to believe that the origin of muscle-pearls is associated with pathological invaginations or immigrations of the epidermis at the points where the muscle-attachment epithelium passes over into the ordinary outer mantle-epithelium. (5) Parenchyma-pearls (which name I apply to Prof. Herdman’s cyst-pearls) may be formed around grains of sand or other foreign particles, organic granular matter of doubtful origin, or bodies composed of varieties of the shell-substance which arise when the normal rhythm of secretion is disturbed (repair-substance). A foreign nucleus is probably rather exceptional. The ultimate factors which give rise to the epidermal sacs in which they are formed have yet to be discovered. Many of them are probably of the same origin as muscle-pearls, except that they arise singly at points where a few muscle-fibres are inserted into the shell, instead of in clusters at the regular muscle-insertions. The dark pseudo-nuclei of these pearls, which may easily be mistaken for the remains of parasites, are usually composed of the repair- substances. (16) Works REFERRED 0. (1) Brepermann, W. 1901.—Untersuchungen tiber Bau und Entstehung der Molluskenschalen. Jenaische Zeitschr. f. Naturwiss. Bd. xxxvi. Hft. 1. pp. 1-164, Taf.i-vi. 1901. (2) Brepermann, W. 1902.—Ueber die Bedeutung von Krystallisationsprozessen bei der Bildung der Skelette wirbelloser Thiere, namentlich der Mol- lusken. Zeitschyr. f. allg. Physiologie, Bd. i. pp. 154-208. Jena, 1902. (3) Bouran, L. 1903.—L’origine réelle des Perles fines. C.R. Acad. Sci., Dec. 14, 1903, t. exxxvil. p. 1073. (4) Bouran, L. 1904.—Les Perles fines, leur Origine réelle. Arch. Zool. Expér., Sér. 4, t. ii. pp. 47-90. 1904. (5) Birscutt, O. 1898.—Untersuchungen iiber Strukturen. Leipzig, 1898. (6) Birscuu, O. 1908.—Untersuchungen iiber organische Kalkgebilde. Abhandl. d. konigl. Gesellsch. der Wissenschaften zu Géttingen, Math.-Phys. Klasse, Neue Folge, Bd. vi.no. 8. 1908. (7) Dusots, R. 1907.—Sur un Sporozoaire parasite de l Huitre perliére (Margari- tifera vulgaris). Son Réle dans la Formation des Perles fines. ‘C.R. Soc. Biol. lxii. 1907, pp. 310-312. | (8) Dusois, R. 1909.—Contribution 4 Etude des Perles fines. Annales de VUniversité de Lyon, n. s., i. Sciences—Médicine, Fascicule 29. 1909. (9) Enrensaum, EK, 1885.—Untersuchungen iiber die Struktur und Bildung der Schale der in der Kieler Bucht haufig vorkommenden Muscheln. Zeitschr. f. wiss. Zool. Bd. xli. 1885, pp. 1-46, Taf. iii. (10) Grarp, A. 1903.—L’origine Parasitaire des Perles d’aprés les recherches de M. G. Seurat. Comptes-rendus des Séances de la Société de Biologie (Séance du 31 Octobre, 1903), t. lv. p. 1222. 1903. (11) Hartey, G. 1889.—The Structural Arrangement of the Mineral Matters in Sedimentary and Crystalline Pearls. Proc. Roy. Soc. vol. xlv. no. 279, pp. 612-614. (12) Hartine, P. 1872.—Recherches de morphologie synthétique sur la production artificielle de quelques formations calcaires organiques. Verhandl. d. Kon. Akad. d. Vetenskapp. Amsterdam, Deel 14, 1872, 85 pp., 4 pls. (13) Herpman, W. A. 1902.—Reports on the Pearl Fisheries of Ceylon. Preliminary Report. Ceylon Sessional Papers, xii. 1902. (14) Herpman, W. A. 1903.—Lecture delivered at the Royal Institution on March 27th, 1903; Abstract in ‘ Nature,’ vol. 67, 1903, pp. 620-622. 350 DR. H. LYSTER JAMESON ON (15) Henpman, W. A., & Hornett, J. 1903.—Note on Pearl-formation in the Ceylon Pearl Oyster. British Association Report, Southport, 1903, p. 695. (16) Herpman, W. A. 1903-6.—Report to the Government of Ceylon on the Pearl Oyster Fisheries of the Gulf of Manaar. London: Published by the Royal Society. 1903-6. Part I. 1908. Herpman, W. A.—Introduction and Narrative, pp. 1-98. ks A Description of the Pearl Banks, pp. 99-121. re 5 Observations and Experiments on the Pearl Oyster, pp. 125-146. Part IT. 1904. Preface, pp. v—vii. Hurrpman, W. A.—History of the Principal Pearl Banks, pp. 1-36. 5 A Anatomy of the Pearl Oyster, pp. 37—76, pls. ix. Surpbtey, A. E., & Horney, J.—Parasites of the Pearl Oyster, pp. 77-106, pls. i.-1v. Part III. 1905. Preface, pp. v—viil. Herpman, W. A. (based on Report and Letters of Mr. Hornett). The Pearl Fishery of 1904, pp. 1-36. Be >, (based on Report and Letters of Mr. Hornetr). The Present Condition of the Pearl Banks, pp. 37-48. Surpiey, A. E., & Hornet, J—FKurther Report on Parasites, pp. 49- 55, plate. Part IV. 1905. Preface, pp. v—vi. Herpmayn, W. A.—The Great Pearl Fishery of 1905, pp. vii-xvi. Part V. 1906. Preface, pp. -vii. Herpman, W. A., & Horney, J.—Pearl Production, pp. 1-42, pls. i-iil. Surety, A. E., & Hornet, J—Cestode and Nematode Parasites from the Marine Fishes of Ceylon, pp. 43-96, pls. i.—v1. Herpman, W. A.—General Summary and Recommendations, pp. 109— 136, plate. (16 a) Herpman, W.A. 1905.—Presidential Address delivered at the Anniversary Meeting of the Linnean Society of London on 24th May, 1905. London: Taylor & Francis, 1905. (17) Herpman, W. A. 1906.—Address delivered at the Anniversary Meeting of the Linnean Society of London on 24th May, 1906. London: Taylor & Francis, 1906. (18) Hesstine, I. 1859.—Die Perlmuscheln und ihre Perlen. Leipzig, 1859. (19) Hernetn, J. 1905.—The Biological Results of the Ceylon Pearl Fishery of 1904. Reports from the Ceylon Marine Biological Laboratory, No. L., 1905, pp. 1-39. (20) Hornet, J. 1905.—Report on the November Inspection of the Ceylon Pearl Banks, 1904. Ceylon Sessional Papers, xi1., 1905. (21) Hornett, J. 1905.—Report on the Placuna Placenta Pearl Fishery of Lake Tampalakamam. Ceylon Sessional Papers, xiv., 1905. ; (22) Hornets, J. 1906.—Report on the Placuna Placenta Pearl Fishery of Lake Tampalakamam. Ceylon Marine Biological Reports, Part II., June 1906, pp. 41-54, plate. (23) Hornett, J. 1906.—Report on the Inspection of the Ceylon Pearl Banks, November 1905. Ceyion Sessional Pavers, xvii., 1906. (24) Huxiry, T. H. 1859.—Tegumentary Organs. Todd’s Cyclopedia of Anat. & Physiol. vol. 5 (Suppl. Vol.). 1859. (25) Jamuson, H. L. 1902.—Gn the Origin of Pearls. Proceedings of the Zoological Society, 1902, vol. i. pp. 140-166, pls. xiv.—xvil. (26) Jameson, H. L. 1903.—The Formation of Pearls. Nature, vol. 67, pp. 280-2, Jan. 22nd, 1903. (26 a) Jameson, H. L. 1912.—An Examination of the Causes ah aye led to the Failure of the Biological work recently undertaken on the Ceylon Pearl] Fisheries. Journal of Economic Biology, vol. vu. pt. 1, pp. 10-22. Feb. 1912. \ (261) Jounstene, J. 1912.—Tetrarhynchus erinaceus van Beneden.—i. Strue- ture of the Larva and Adult Worm. Parasitology, vol. iv. no. 4, January 8, 1912, pp. 364-415, pls. xix.—xxiv. (27) Kexaart, EK. HL. 1857. —Introductory Report on the Natural History of the Pearl Oyster of Ceylon. Trincomalee, 1857. (27a) Linton, E. 1891. —Notes on Entozoa of Marine Fishes of New England, with Deseriptions of several New Species—Pt. II. Report U.S. Commission of Fisheries for 1887 [1891], pp. 719-899, pls. 1.—xv. THE CEYLON PEARL-OYSTER. 351 (276) List, T. 1902.—Die Mytiliden des Golfes von Neapel. Fauna und Flora des Golfes von Neapel: 27. Monographie. Berlin, 1902. (27c) Mirsuxort, K. 1902.—The Cultivation of Marine and Fresh-water Animals in Japan. Bulletin of the U.S. Bureau of Fisheries for 1904, vol. xxiv. 1905, pp. 259-289, pls. i.—xi. (28) Moynrer pe Virtieporx, R. 1892.—Recherches sur la formation et l’accrois- sement de la Coquille des Mollusques. Journ. de l’Anat. et dela Physiol. t. Ixxviil., 1892. (29) Minter, F. 1885.—Ueber die Schalenbildung bei Lamellibranchiaten. Schneider, Zoolog. Beitriige, Bd. i. Hft. 11. pp. 206-246, Taf. xxvili—xxx. (80) Pacrnstecner, H. A. 1858.—Uber Perlenbildung. Zeitschr. f. wiss. Zool. Bad. ix. pp. 496-506, Taf. xx, 1858. (81) ReaumeR. 1709.—De la formation et de Vaccroissement des Coquilles des animaux. Hist. de Acad. Roy. des Sciences; Paris 1711. Mém. Anneé, 1709. (32) Romer, O. 1903.—Untersuchungen tiber den feineren Bau einiger Muschel- schalen, Zeitschr. fiir wiss. Zool. Bd. lxxv. Hft. iii. 1903. (33) Rupeer, A. 1911—Zur Kenntniss der Schalenregeneration bei der Fluss- perlmuschel. Zoologischer Anzeiger, 7. Marz, 1911, Bd. xxxvii. Nr. 8/9, pp. 169-172, (84) Russet, A. 1911—Die Entstehung der Perlen bei Margaritana margari- tifera. Zoologischer Anzeiger, 25. April, 1911, Bd. xxxvii. Nr. 19/20, pp. 411-416. (84a) Russet, A. 1911.—Ueber Perlen und Perlbildung bei Margaritana margaritifera nebst Beitragen zur Kenntniss ihrer Schalenstruktur. Marburg, 1911. Pp. 80, two pls., and numerous text-figures. (35) Srurart, G. 1904.—Sur la Biologie des Huitres perliéres et nacriéres des Iles Gambier. C.R. Soc. Biol. tom. lvi. 1904, No. 7 (26 Février), pp. 294-295. (86) Srurar, G. 1906.—Sur un Cestode parasite des Huitres perliéres déterminant la production des perles fines aux Iles Gambier. Paris, C.R. Acad. Sci. tom. 142, 1906, pp. 801-803. (87) Seurar, G. 1906.—La Nacre et la Perle en Océanie.—Péche.—Origine et Mode de Formation des Perles. Bull. Mus. Oceanogr. Monaco, No. 75, 1906. (88) Souruwett, T. 1910.—On the Determination of the Adult of the Pearl- inducing Worm. Ceylon Marine Biological Reports, Part IV. pp. 169-172. (89) Sournwert, T. 1910.—A Note on Endogenous Reproduction discovered in the Larve of Tetrarhynchus unionifactor inhabiting the Tissues of the Pearl Oyster. Ceylon Marine Biological Reports, Part IV., May 1910, No. 7, pp. 173-174. (40) Souruwett, T. 1911.—Physical and Biological Conditions on the Pearl Banks. Ceylon Marine Biological Reports, Part V., March 1911, pp. 191-194. (41) Souruwett, T. 1911.—Further Notes on the Determination of the Adult of the Pearl-inducing Worm. Ceylon Marine Biological Reports, Part V. pp. 213-215. (41a) Sourmwett, T. 1911.—Description of Nine new Species of Cestode Para- sites, including Two new Genera, from Marine Fishes of Ceylon. Ceylon Marine Biological Reports, Part v. No. 18, pp. 216-225, plates. 1911. (42) Souruwett, T. 1911.—Some Notes on the Ceylon Pearl-inducing Worm. Spolia Zeylanica, vol. vii. Part xxvii., May 1911, pp. 124-134. (43) Steinman, G. 1901.—Ueber die Bildungsweise des dunkeln Pigments bei den Mollusken, nebst Bemerkungen tiber die Entstehung von Kalkkarbonat. Ber. naturf. Ges. Freiburg, Bd. xi. 1899-1901, pp. 40-45. (44) Srempevy, W. 1898.-—Beitrage zur Kenntniss der Nuculiden. Zool. Jahrb., Supplement-Band iv. : Fauna Chilensis, Bd. i. pp. 339-430, Taf. 22, 25. | (45) SrempPett, W. 1900.—Ueber die Bildungsweise und das Wachstum der Muschel- und Schneckenschalen. Biol. Centralblatt, Bd. xx. Nos. 18- 22. 1900. ik (46) Tutere, J. 1893.—Beitrage zur Kenntnis der Mollusken.—II. Uber die Mol- luskenschalen. Zeitschr. f. wiss. Zool. Bd. lv. 1893, pp. 220-250, Taf. xi. (47) Tuxtpere, T. 1882.—Studien tiber den Bau und das Wachsthum des Hummerparzers und der Molluskenschalen. Kongliga Svenska Vetensk.- Akad. Handlingar, Bd. xix., No. 3, 57 pp., 12 Taf. 1884. (48) Wirtry, A. 1907.—Report on the Window-Pane Oyster (Placuna placenta, “Muttuchchippi”) in the Backwaters of the Eastern Province (June 1907). Spolia Zeylanica, vol. v. part xvii., Nov. 1907, pp. 33-56. (49) Wriuirey, A. 1909.—Report of the Marine Biologist for 1908. Ceylon Administration Reports for 1908, Colombo, p. G. 1. (50) Lease of the Ceylon Pearl Fisheries. Ceylon Sessional Papers, x1., 1907. Fig. gg Fic. iQ DR. H. LYSTER JAMESON ON (17) EXPLANATION OF THE PLATES. (The magnifications quoted are only approximate.) PrateE XXXIII. 1. Cestode larva (Tylocephalum ludificans or T. minus) in the act of migrating through the tissues of Margarivifera vulgaris. Drawn trom one of Prof. Herdmman’s slides. ‘The larva measured 12 mm, pa., parenchymatous subepidermal tissue ; ¢.¢,f., connective-tissue fibres. 2. Small larva, Tylocephalum minus, measuring ‘08 mm., in the muscular tissue of the mantle of MW. vulgaris, without a surrounding connective- tissue cyst. Fyrom one of Prot. Herdman’s slides. m-.f., muscle-fibres in cross-section ; ep., epidermis. 3. Part of the fibrous cyst surrounding an example of the smaller parasite (Lylocephalum minus). In this case the parasite measured ‘08 mm. m diameter. J.¢., liver-tubules; 7./., inner, highly nucleated layer of the cyst. < 800. 4. Margaritifera vulgaris. pithelial cells from the muscle-attachment, showing the connection between the cells and the muscle-fibres. < 1000. .4a. Margaritifera vulgaris. Muscle-attachment epithelium, showing cells drawn out in fixation, and connective-tissue elements between their bases. X 1200. Poate XXXIV. 5. Mytilus edulis. Section through the posterior adductor muscle-insertion and decalcitied hypostracum. mus., muscle-fibres; hy., hypostracum, Which remains adherent to the muscle-attachment: epithelium, ep. ; hy.’, segment of hypostracum, corresponding to single epidermal cell; nac., nacreous layers of the shell, which have torn away from the hypo- stracum; ct., connective-tissue fibres, joining the muscle-fibres to the attachment-epithelium. Preparation XXXIX. X 500. 6. Margaritifera vulgaris, Persian Gulf. The part represented at A in text-figure 35, showing the point of origin of a new lip-lappet of the shell. 1., 1.’, two successively formed lappets or marginal processes; pr., pr, prisms of same; s.pr., s.pr.’, conchyolin-septa of the prisms; b.m.pr., conchyolin basal membrane of the prismatic substance of the first lappet ; per., periostracum of the second lappet, which appears to be nothing more than the outer conchyolin-membrane of the prismatic substance ; x, point at which the second lappet arises from the first, the peri- ostracum of the seeond lappet being continuous with the basal membrane of the first; y, irregular prismatic substance secreted at the junction of the two lappets. Preparation X. X 300. Fic. 6a. Margaritifera vulgaris, Persian Gulf. Decalcitied shell showing junction g g J J Fig. between prismatic substance and nacre. pr., prisms; sep., conchyolin- septa between same; sep.’, the same in surface view; anuw., annular thickenings of the septa; p7r.b., basal conchyolin of the prismatic layer ; con., connecting layer of alveolar conchyolin between the prisms and the nacre; nac., nacre. Prepayvation XI. X 400. 7. Margaritifera vulgaris, Persian Gulf. “ Lingah Shell” from London mariet. Section ground from an old-heavy shell. Portion of the adductor- scar, showing the hypostracum, /y., covered over in the direction of the umbo by nacre, zac.’ ; wac., nacre underlying the muscle-scar, and secreted before the muscle-attachment had moved to this place ; hy.’, hy.'’, extensions of the hypostracum interstratified. with nacre. Preparation LXXV. X 120. - Pratt XXXV. 8. Muscle-pearl and hypostracum “cyst,” from the insertion of the posterior pedal levator muscle of Margaritifera vulgaris. Froma Ceylon specimen given to me by Professor Herdman. The pearl is enclosed in a sac (which has been ruptured by gas-bubbles in the decalcifying process), consisting mainly of ordinary shell-secreting epithelium, but lined at one pole with muscle-attachment epithelium (m.ep.’). Opposite the ordinary epitheliam THE CEYLON PEARL-OYSTER. 353 the pearl consists of typical coats of nacre; but at the point where the sac is lined with attachment-epithelium the pearl consists of hypostracum, which also (or a substance analogous to it) lines the central cavity. Beside the pearl, at ¢. is a cyst-like hypostracum-pearl, comparable to the lining of the adjoining nacreous pearl. This hypostracum-pearl consistsof a cavity, lined with hypostracum-like substance (hyp.’), and on two sides it shows muscle-attachment epithelium, m.ep.’, but it has not acquired a lining of ordinary nacre-secreting epithelium, and hence no nacreous coats have arisen. c., cyst-like cavity of hypostracum-pearl ; ep., shell-secreting epidermis ; ep.’, epidermis of pearl-sac ; m.ep., muscle-attachment epidermis ; m.ep.’, do. of pearl-sac; m.ep.’’, do. of hypostracum-pearl ; m., muscle- fibres; par., parenchyma; hyp., hypostracum which lines the muscle pearl; hyp.’, do. of the hypostracum-pearl. Preparation IV,9. XX 100. Fig. 9. A muscle-pearl in the free mantle, froma slide in Prof. Herdman’s collection. Fig. Fig. Fig. ie. 10. ig. 13. ig. 14. 15. 17. The area where the muscle-attachment epidermis is attached to the pearl is relatively very small. The greater part of the pearl-sac is composed of ordinary nacre-secreting epidermis, and consequently the pearl is composed of nacre at all parts but one. o.ep., outer shell-secreting epidermis ; i.ep., inner ciliated epidermis of the mantle-cavity ; par., subepidermal parenchyma-cells, surrounding the pearl-sac ; m.ep., muscle-attachment epithelium, where hilum of pearl was attached ; musc., muscles of mantle ; sac., pearl-sac ; nae., nacre; rep.nac., granular repair-nacre, around central part of pearl; hyp., hypostracum. X 70. PuatE XXXVI. An early stage of a muscle-pearl, from one of Prof. Herdman’s slides. sac., pearl-sac; ., nacre; par., parenchyma; m., muscle-fibres; hyp. hypostracum-like cyst, around which the pearl is formed ; m.ep., muscle- attachment epithelium; c., a hypostracum-pearl. X 65. . A cyst-like hypostracum-pearl in the muscle-bundle, without any apparent epithelial sac. From one of Professor Herdman’s slides. ‘The cyst adjoins the wall of a sac, ep.p.s., in which a muscle-pearl was contained. hy., hypostracum ; m., muscles ; par., parenchyma ; 0.ep., outer shell-secreting epidermis; ep.p.s., epidermis of pearl-sac. X< 400. . Centre of the decalcified muscle-pearl which occupied the sac adjoining the hypostracum-pearl shown in fig. 11. ¢., central cavity; g7., granules in central cavity ; 2., nacre. > 500. Centre of a decalcified pearl, close to the mantle-margin, in one of Prof. Herdman’s slides. ¢., central cavity ; »., nacre ; rep.m., Yepair-nacre with radial reinforcements ; /.c., lining of the central cavity. > 300. PLatTE XXXVII. Four pearls “in ovary” of Margaritifera vulgaris, from Dr. Kelaart’s material in the British Museum. The pearls are close together as shown, but their centres have been brought into the same plane in the drawing to show the “nuclei.” Each pearl is surrounded by a mass of subepidermal parenchyma, par. ep., outer epidermis; ov., ovarian tubules ; m., muscle- bundles. Preparation XXVII, 8. ~X 30. The centre of the pearl shown in the top left-hand corner of fig. 14. e., central cavities ; nw., nucleus-like matter, probably of the nature of conchyolin, contained in same; rep.n., repair-nacre, with granular structure, tollowing upon the cavity; »., ordinary nacre of the pearl. Preparation XXVII, 8. x 400. . The central portion of the pearl shown on Plate XLIV. fig. 48. 2.. central nacre; m.’, peripheral nacre; c¢., central cavity; g7.l., granular layer, causing the opaque yellowish appearance of the central mass. Preparation LXXI sg. xX 70. PuatE XXXVIII. A portion of the granular layer of the pearl shown in fig. 16, more highly magnified. ., central nacre; m.’, peripheral nacre; g7., granular layer, suggesting dead cells ; am.,am.’, two layers of amorphous horny substance. Preparation LXXI gs. xX 400, Proc, Zoou. Soc.—1912, No. XXIII. 23 3504. DR. H. LYSTER JAMESON ON” Fig. 18. The centre of the same pearl, consisting of a cavity, about *08 mm. in diameter, surrounded by granular repair-nacre; the cavity contains a few nregular strands or lamine of conchyolin-like substance, together with certain granular bodies, possibly of cellular origin. Preparation LXXI vg. x 450. Fig. 19. Group of muscle-pearls and hypostracum-pearls, from an old unlabelled example of Margaritifera vulgaris in the British Museum. ‘The centres of the pearls have been brought into the same plane in the drawing. The pseudo-nuclei range from ‘08 mm. to °15 mm. in diameter. At the bottom and on the left-hand sides of the sketch are two pearls with eccentric pseudo-nuclei, in these cases composed of hypostracum, showing that the nacre-secreting epithelium arose on one side of the sac only. The preservation does not allow of any histological details of the tissues being shown. Four hypostracum-pearls are also shown. nae., nacre; nw., columnar pseudo-nucleus; nz.’, hypostracum pseudo-nucleus, only partly surrounded by nacre; /y.p., hypostracum- pearls: muse., muscle-bundles. Preparation XXVII, 4. X 30. HAUTE) NOXGNGIEXS Fig. 20. Centre of the pearl shown on the upper side of fig. 19. mac., nacre; col., columnar substance ; am., amorphous substance; g7., granules in central cavity. Preparation XX VII, 4. > 350. Fig. 21. A hypostracum-pearl, decalcified. gi., granules in central cavity; am., amorphous substance; /y., organic residue of the hypostracum. Preparation XXVII,1. > 50. Fig.21a.Part of a section ground through the middle of a hypostracum-pearl, showing the columnar and stratified nature of its substance, and the small central cavity. From an unlabelled specimen in the British Museum. Preparation LXXVIII c. xX 70. Fig, 22. Portion of the mantle of Margaritifera vulgaris, near the margin, from a second unlabelled specimen in the British Museum. Cleared in oil of cloves, aud examined entire before decalcification. ‘The specimen shows a number of hypostracum-pearls iz situ. At nac.is seen a large hypostracum- pearl in course of transformation into a nacreous pearl by the deposition of nacreous layers around it. Preparation XXIX. X 20. Fig. 23. The same decalcified and examined in oil of cloves. mac., as above. X 20. Prave XL. Fiz. 24. A double nucleus, with abundant contents, from a pearl in the same series of sections as figs. 19-21. gi, granular substance, apparently derived from dead organic matter; a@m., amorphous cuticle-like layers ; am.’, a more deeply staining portion of the same substance, immediately surrounding the granular contents of the nucleus ; col., columnar substance ; nac., nacre. Preparation XXVII,7. X 250. Fig. 25. A small hypostracum-pearl. Central cavity without contents. Preparation XXVIII, 11. x 100. Fig. 26. A double hypostracum-pearl, forming the nucleus of a nacreous pearl. am., (2) amorphous substance; hy., hypostracum ; hy.’, do. at periphery of amorphous substance; nac., nacre; nac.’, columnar repair-substance. Preparation XXVII,11. xX 75. Vig. 27. Small pearl, with nacreous substance overlain hy hypostracum. ¢., central cavity, containing afew granules; am., amorphous substance which passes over into col., columnar substance; nae., nacre, which is succeeded by hy., a layer of hypostracum, forming the outermost layer of the pearl. This specimen shows well the difference between the reaction to stain of hypostracum and the other substances, e. g. columnar substance. Preparation XXVIJI,7. X 350. Fig. 28. Pseudo-nucleus of the left-hand constituent of the double pearl shown in fic. 49 (Plate XLIV.). From one of the unlabelled specimens of Margaritifera vulgaris in the British Museum. c., central mass composed of (?) amorphous substance and granules; col., columnar substance ; col.’, outer layers of the same, which pass over imperceptibly at one point into nae.’, nacreous substance; nac., complete layers of nacre around nucleus; am., horny layer, probably composed of amorphous substance : Co t t - Cy I THE CEYLON PEARL-OYSTER, col.”, incomplete columnar layer; nac.'’, nacreous substance of the pearl. Preparation XLIII B. xX 75. Margaritifera vulgaris, Persian Gulf. Portion of the repair-substance formed inside the shell to close a large hole made by a borer of some kind in the lateral region, below the umbo. am., amorphous substance; y, outer surface of repair-membrane ; a, a’, cracks in the outer face of the amorphous substance; col., columnar repair-substance; col.’, stratified do.; tr., ér.’, transitional substance (granular repair-nacre) from columnar repair-substance to nacre; mac., nacre. Preparation LXXVI. x 400. Fig. 29a. Margaritifera vulgaris, Persian Gulf. From a section through a blister Fig. 30, Fig. 31. Fig. 32. Fig. 33. Fig. 34. Fig. 35. Fig. 36. Fig. 37. on the shell-margin, formed over a Lewcodore tube. am., amorphous repair-substance; a@/v., the same with alveoli containing carbonate of lime; pr., prismatic substance. Preparation XI. X 500, Prats XLI. Margaritifera vulgaris; Dr. Kelaart’s material. Sections showing junc- tion between two of the constituents of a “multiple pearl,’ with the various abnormal products which arose in association with the disturbances caused by the fusion of the two pearl-sacs, and the retreat of the wedge- shaped plug of tissue when its connection with its fellow of the opposite side was broken down by the absorption or degeneration of the membrane separating the two pearls. p., p.’, outer nacreous layers of the two pearls ; rep.nac., granular repair-nacre; col., simple columnar substance, analo- gous to that found in the nuclei of some pearls; am., amorphous substance showing rough stratifications, perhaps corresponding to pauses in the retreat of the wedge of tissue; ¢., transition from amorphous substance to columnar substance; ¢7.’, transition from amorphous sub- stance to granular substance ; nac.’, nacre of the compound pearl embracing both constituent pearls. Preparation LXXIc. X 300. Margaritifera vulgaris. Unlabelled specimen, British Museum. One end of the suture between the fused pearls shown in fig. 49, Plate XLIV. nac., nac.’, the nacreous layers of the two pearls; col., col.’, columnar substance, secreted after the epithelium had, through atrophy, lost its power of producing nacre; ep., ep.’, the degenerated remains of the epithelia of the pearl-sacs ; par., the remains of the intervening paren- chyma. Preparation LXIII Bp. X 350. From the middle of the same suture; in this case the outlines of the parenchyma-cells, par., are still visible. ep., remains of the epithelia of the pearl-sacs. XX 350. Parenchyma-pearl in situ in the tissues of Margaritifera vulgaris, from the Persian Gulf. _ep., outer shell-secreting epithelium ; ep.’, epithelium of pearl-sac ; par., subepidermal parenchyma ; g/., gland-cells in same ; musc., muscular coat of the visceral mass ; mause.’, musculature to wall of stomach : C.T., connective-tissue of visceral mass; ov., tubules of ovary; col., columnar substance forming the centre of the pearl; nae., nacreous portion of the pearl. Preparation LXIV s. xX 80. Centre of a pearl from another example from the Persian Gulf. gi., granular matter; am., (?) amorphous substance ; nac., nacreous layer, immediately surrounding the “ nucleus”; nac.’, outer nacre; col., columnar substance ; col.’, imperfect layer of same, passing over laterally into nacre. Preparation LXIV c. X 250. The central, spherocrystal-like pseudo-nucleus of the pearl shown in figs. 50 & 50 a (Plate XLV.) ; from the sample of pearls purchased in Ceylon. grm., granular repair-nacre ; am., amorphous substance. Preparation XLII. 400. ACD eal: The pseudo-nucleus of the pearl shown in fig. 52 (Plate XLV.) ; from series purchased in Ceylon. gr., granular substance in central cavity forming the true nucleus; am., amorphous substance ; nw., pseudo-nucleus, which here possesses a highly alveolar structure; col., columnar repair-substance passing over laterally into mae., nacre. Preparation LIII. > 70. Alveolar columnar repair-substance and radially reinforced nacre, from the pseudo-nucleus surrounding a sand-grain (or other hard body that broke away) in a pearl from the same series. am., amorphous substance, forming 23% 356 Fig. Fig. Fig. Fig. Fig. Fi: IQ 38. 39. ig. 40. ig. 4d. ig. 42. 43. 44, DR. H. LYSTER JAMESON ON the innermost layer of the columnar pseudo-nucleus, col.; nac., nacre ; nac.’, radially marked, catenuiated variety of nacre, characterised by radial rows of junctions which occur in small groups between conchyolin- layers (june.); nae.’’, the normal nacre, passing over into this specialised variety of nacre. Preparation LIV G@. X 300. Tangential section through the alveolar-columnar substance shown at col, in fig. 87. X 300. Tangential section through the radially catenulated repair-nacre, shown at nac.’ in fig. 37. junc., the groups of junctions in radial rows, seen in surface view. The section is near the inner surface of this layer. X 300. Centre of the imperfcetly decalcified brown pearl, shown in Pl. XLVI., fig. 57. nu., nucleus with rhombohedra of calcite ; am.’, lining of amorphous substance; col., columnar layer; col.tr., transition-layer from alveolar-columnar substance to amorphous substance; am., amorphous substance, with scattered alveoli, containing calcium carbonate. Pre- paration XL. X 2650. Part of the same pearl, external to that shown on fig. 40, showing the transition from amorphous substance, am., with scattered alveoli, through an intermediate substance, ¢7., to needle-like prismatic substance, col. x 250. Transition from the needle-like prismatic substance, col., shown in fig. 41, to the ordinary prismatic shell-substance, pr., similar to that of the shell. al., minute alveoli in the thickenings of the walls of the prisms, similar to those observed by Romer (32). X 250. PrarE XLIIL. A portion of the repair-substance in the body of a pearl, shown at col. in fig, 86, showing transitions from amorphous substance to nacre. nu., outer part of the pseudo-nucleus; am., amorphous substance, with alveoli, which passes over into finely columnar substance, col. This in turn goes over through granular repair-nacre, gr., into normal nacre, nac.’, and is followed by layers of normal nacre (nac.) externally. Pre- paration LIIT. X 400. : Portion of the contents of the central cavity of one of the pearls purchased in Ceylon; showing also a portion of the columnar substance which surrounded the centre. The contents drawn are selected from a number of the sectioas in the series cut from this specimen. mac., nacreous substance of the pearl; col., columnar repair-substance surrounding the nucleus; am.,@m.’, amorphous substance; dia., diatoms; spic., fragments of sponge-spicules ; veg., vegetable débris. Preparation LIV 5. X 500. 5. Fragment of a Radiolarian shell, from the centre of another of the same lot of pearls. Preparation LIV £. X 600. Prare XLIV. s, 46, 46 a. Pearl from a cluster of pearls in one of Dr. Kelaart’s specimens. Decalcitied and examined, 4.6, entire in oil of cloves, 46 a, in section. The diameter of the pearl was just 2 mm., that of the central denser part was 13mm. There is a simple central cavity. Preparation XVI. X 27. Vigs. 47, 47 a. Another pearl from Dr. Kelaart’s material, decalcified and examined, 47, entire, and, 47 a, in section. The diameter of the pearl was 2mm. ; that of the dark, opaque, yellowish centre rather over 1 mm. Examined entire the nucleus appears amorphous, and might well be mistaken for the dead remains of a parasite; but this peculiarity was found, on sections being made, to be due to a break in the continuity of the nacreous layers and the interpolation of a dark layer, composed of irregularly calcified conchyolin, and granules which are probably of extraneous origin. ‘There is a small central cavity, as in the rest of Dr. Kelaart’s pearls, with a plug of conchyolin-like substance at one side. g7., granular dead matter; col., columnar substance; , nacre. Preparation XV. X 27. Vig. 48. A “double” pearl from Dr. Kelaart’s material, decalcified, cleared, and examined entire. Sections through this pearl are shown on Plates XXXVII. & XXXVIII. figs. 16-18. The pearl was 2°25 nm. in diameter. The pseudo-nucleus was a dark opaque body, about 0°5 mm. in diameter, similar to that shown in fig. 47, and might easily be taken, on examination ot the entire pearl, for the shrivelled remains of a dead parasite. Sections THE CEYLON PEARL-OYSTER. ao showed that here again the real nucleus was a cavity containing strands or sheets of conchyolin-like substance and a few granular bodies, perhaps of cellular origin (Plate XXXVIII. fig. 18); while the dark appearance of the central mass was due to the interpolation between the proper nacreous layers ofan abnormal pathological product. Preparation LXX Iv. xX 27. Fig. 49, A double pearl from one of the unlabelled specimens in the British Museum; decalcified, cleared, and examined entire. The nucleus of the left-hand constituent is figured on Pl. XL. fig. 28, the characters of the substance at the suture between the two pearls at figs. 31 & 32 on Plate XLI. In the pseudo-nuclei of these pearls the columnar substance is stratified. Preparation LXIII sp. X 27. PLATE XLY. Figs. 50, 50 a. The central portion of a white porcellanous spherical pearl, from the sample of pearls purchased for me in Ceylon by the Ceylon Company of Pearl Fishers, Ltd. Fig. 50, decaicitied and examined whole in oil of cloves. Here the nucleus, when examined whole, might well be mistaken for a small Trematode. Fig. 50 a. Section through the centre of the same pearl. ‘The pseudo-nucleus is seen to cousist of an irregular nacreous body, shown in fig. 35 (Plate XLI.) to be granular repair-nacre, surrounding a minute sphwrocrystal-like mass; about 0°08 mm. in diameter. Pro- paration XLIII. x 27. 51. Another pearl from the same collection. An oval pearl, of fine quality, 35 mm. X 3mm. in diameter. This pearl shows a tract of stratified columnar and granular repair-substance, extending outwards from the pseudo-nucleus and passing over laterally into the nacre, Preparation LI. X 20. Fig. 52. Another pseudo-nucleus, from a pearl in the same collection. This was a small spherical pearl of fine quality, about 2 mm. in diameter. The columnar substance here, col., is alveolar in structure, and surrounds a central cavity containing afew granules. Fora section of the centre of this pearl, see fig. 36 (Pl. XLII.) Preparation LIII. X 27. Figs. 53, 53a. Centre of another pearl from the same series. The pearl was oval, about 3 mm. in diameter, with a faint zonar constriction and a rather coppery tint. Examined entire (fig. 50) it shows a large pseudo-nucleus, over a millimetre in diameter, which falls into three layers. It also shows a blemish in the nacre, coated over with repair-substance. Fig. 53 a shows the same in section, The columnar repair-substance is finely reticulated or alveolar. The blemish is caused by a few granules, which have found their way into the pearl-sac and have been covered over with columnar repair-substance, which passes over laterally into ordinary nacre, Preparation LIV. xX 27. Figs. 54,54 a. Fig. 54. Central portion of another pearl, which measured about 3mm. X 2°75 mm. _ A pearl of fine colour, but with slightly irregular surface. he nucleus of this pearl is a sand-grain, enclosed in an opaque yellowish coat, probably consisting of repair-substance. At one pole is seen a process of repair-nacre, but, except for this, no columnar substance appears to surround the grain. Fig. 54a. The sand-grain, dissected out from the above preparation. Preparation LII. X 27. PratE XLVI. . 55. Fine spherical pearl, from the same series, about 2 mm. in diameter. Nucleus a grain of sand surrounded by a thin layer of columnar substance, thickened at one pole. Preparation LIV u. X 27. Fig. 56. Another pearl from the same series, a small spherical pearl about 2 mm. in diameter. ‘The nucleus is a grain of sand, forming the centre of a typical pseudo-nucleus of columnar substance. Preparation LIV a. xX 27. Fig. 57. A brown pearl, spherical, 3 :mm. in diameter, formed of the prismatic substance. Fromthesame collection. nw., pseudo-nucleus ; co/., columnar substance ; am., amorphous substance; col.’, fine columnar-prismatic sub- stance ; pr., ordinary prismatic substance ; 6/., blister formed over intrusive foreign matter. For the several substances of this pearl, more highly magnified, see Plate XLII. figs. 40-42. Preparation XL. X 27. 358 _ MR. ROBERT SHELFORD ON Fig. 58. Tylocephalum ludificans, sp.n. Type. Section through an example in the tissues of the Ceylon Pearl-Oyster in Professor Herdman’s collection. Slide 94 of Professor Herdman’s series. a@., armature of collar. This shows the myzorhynchus of “ T'ylocephalum” form, due to the posterior face (m.p.) being contracted and its surface thrown into folds and the anterior tace (m.a.) stretched. Compare the adult Tylocephala im figs 61 & 62, and also the species shown in fig. 65. X 70. Fig. 59. Section through another example of the same species, showing the “ Cepha- lobothrium’’-form of myzorhynchus; here the posterior surface of the myzorhynchus (m.p.) is tense, and its anterior surface (m.a.) is thrown into folds. a, armature of collar. (Compare theadult worm in fig. 66.) X 70. Fig. 60. An adult worm, which may be the adult of TLylocephalum ludificans, from the spiral intestine of Aétobatis narinari. X 6. From Dr. Shipley’s collection. Prare XLVII. Fig. 61. The head of the worm shown in fig. 60, viewed as a transparent object. m., myzorhynehus; s,s’, s’’, three of the four marginal suckers; a., armature of collar ; seg., first proglottides. X 70. Fig. 62. The same, in section; letters as above. X 70. Fig. 638. Armature of collar of same, about point a in fig. 62. XX 1000. Fig. 64. Penultimate segment of same. Fig. 65. Head of Tylocephalum uarnak from Trygon warnak. From a slide in Dr. Shipley’s collection. my., myzorhynchus, which here is fully protruded ; ma., anterior face of same; mp., posterior face; s, s’, s’’, s’’’, the four marginal suckers. X 46. [ Vig. 66. Head of Cephalobothrium aétobatides from Aétobatis narinari. From a specimen in Dr. Shipley’s collection. Letters as above. X 70. 19. Mimicry amongst the Blattidee ; with a Revision of the Genus Prosoplecta Sauss., and the Description of a new Genus. By Roperr Saetrorp, M.A., F.Z.5. [Received October 7, 1911: Read February 20, 1912. | (Plate XLVIII.* and Text-figures 42-46.) Speaking in general terms the Blattidee may be regarded as a somewhat defenceless group of insects, preyed upon by numerous enemies both vertebrate and invertebrate, to escape which they must rely on their skulking, cryptic habits, and on a high degree of speed when disturbed. In accordance with their cryptic mode of life most cockroaches are obscurely coloured, harmonising more or less perfectly with their inanimate surroundings, or, at any rate, displaying no conspicuous markings to attract the attention of potential foes. Exceptions to this cryptically coloured type of cockroach, how- ever, exist In some numbers. and are dealt with in the following pages. The Australian continent is the headquarters of a group of Blattidee which presents all the features customarily associated with extreme unpalatability. This group is the Polyzosteria section of the sub-family Blattine. Nearly all the species are apterous and expose themselves freely, and many are endowed with a most repulsive odour. Mr. W. W. Froggatt informs:me that Polyzosteria limbata Burm., P. cuprea Sauss., and others of this * For explanation of the Plate see p. 376. ae Horace Knight del.et lith MIMETIC COCKROACHES AN] D BEETLI 24 West, Newman chromo EF MODELS. MIMICRY AMONGST THE BLAT'TIDA, 359 genus and of Platyzosteria Br., ave fond of sunning themselves on the tops of posts and tree-stumps. Commander J. J. Walker when collecting in Australia frequently encountered a species, Cosmozosteria lateralis Walk., which emitted so vile a smell that he always refrained from touching it. ‘This species is russet- brown in colour with some aviable yellow markings on the thoracic and abdominal tergites, and on each posterior angle of the ninth abdominal tergite is a brilliant orange-red spot ; when the insect is at rest these two spots are almost concealed, the ninth tergite being somewhat retracted within the preceding one, but on the approach of an enemy the apex of the abdomen is elevated — and slightly distended so that the orange spots become conspicu- ously displayed to view. genicular spines on mid and hind femora; front tibie unarmed except for three apical spines, mid and hind tibie with one pair of basal and two apical spines above, with ten spines in a double row and two apical spines below. Total length 13-5 mm.; length of body 11 mm.; length of tegmina 9°5 mm. ; pronotum "4 mm. x 4 mm.; hind femora 4 mm.; hind tibize 4 mm.; hind tarsi 3 mm. Hab. Uncertain, but probably near Rro DE JANEIRO. One example (Miers collection, Oxford Museum). The species 1s very like a Telephorid beetle. MELYROIDEA MAGNIFICA, sp.n. (VI. XLVIII. fig. 18.) 2. Head bright rufous, maxillary palpi piceous, antenne piceous, except for three joints beyond the middle, which are testaceous, slightly incrassated in the middle. Pronotum bright rufous, quadrate, very slightly broader anteriorly than post- eriorly, all the borders somewhat reflexed, disc with two antero- lateral crescentic depressions. Tegmina green, the humeral angle and the part of the right tegmen overlapped by the left dark shining blue, densely reticulated but the veins elevated, mediastinal vein short, radial vein bifurcated from near the base, six highly irregular and branched costal veins, ulnar vein with three ramose branches, apex of anal vein attaining a point at 376 MR. H. WALLIS KEW ON THE more than one third of the sutural margin. Wings very dark fuscous. Abdomen, cerci, and legs dark blue with metallic reflections, supra-anal lamina trigonal, sub-genital lamina cleft and valvular in appearance; cerci very long, with sparse erect pubescence, not acuminate. Formula of apical spines * e = no genicular spine on front femora; front tibie with three apical spines and one spine beneath, mid and hind tibie with two widely separated spines above, four apical spines and a double row of spines beneath. Total length 14 mm.; length of body 11 mm.; length of tegmina 11°5 mm. ; pronotum 2°8 mm. x 3 mm. Hcuapor. One example (Saunders collection, Oxford Museum). This gorgeous little cockroach is also very like a Telephorid, but I have not been able to match it with any particular species. In the preparation of this paper I have been much indebted to the kind assistance of my friend, Mr. G. J. Arrow, who has diligently searched the rich collections of Coleoptera in the British Museum for models to some of the remarkable mimetic cockroaches described above. Mr. Arrow has also supervised the preparation of the plate accompanying this paper. EXPLANATION OF PLATE XLVIII. Fig. 1. Megapyga eximia Boh. Fig. 12. Leis dunlopi Crotch. 2. Prosoplecta bipunctata Br. 13. Prosoplecta semperi, sp. 0. 3. Oides biplagiata Jac. 14. P. quadriplagiata Walk. 4. Prosoplecta trifaria Walk., 3. 15. P. mimas, sp. n. 5. P. coccinella Sauss. 16. P. rufa Karby. 6. P. nigra, sp. n. 17. Melyroidea mimetica, sp. n. 7. P. gutticollis Walk. 18. MW. magnifica, sp. n. 8. Prioptera sinuata Oliv. 19. Prosoplecta calophoroides, 9. Prosoplecta nigroplagiata,sp.n. sp. 0. 10. Oides biplagiata Jac., var. 20. Anisolemnia distaura Muls. 11. Prosoplecta trifaria Walk., 2. 21. Celophora formosa Crotch. 20. On the Pairing of Pseudoscorpiones. By H. Watuis Kew, F.Z:8. [Received January 20, 1912: Read February 6, 1912. ] (Text-figures 47-50.) 1. Introduction. The breeding habits of Arachnida are of special interest from the fact that in no other Class do we find so great a diversity of method *. Much attention has been paid to the subject, and the main facts are established for most of the Orders. For Pseudo- scorpiones, however, scarcely anything is known. Résel von Rosenhof, so long ago as 1755 (1), tells us that he kept these animals together for a long time in the hope of seeing * Cf. Pocock (19), p. 2. PATRING OF PSEUDOSCORPIONES. Sa their pairing, yet without success. So also McIntire (5), who had great experience with several species in captivity, watched patiently for amiable traits, but all in vain. Schtschelkanowzeff, in fact, appears to be the only author who has seen the pairing of any animal of this Order. He states, in a memoir published in 1910 (17), that he saw this act frequently in a species of Chelifer (Chernes) ; and he has established the fact that fertilization is effected without intromission of a copulatory organ. But he did not see exactly what took place ; and the remarkable details of the process remain, it is believed, quite unknown. Mr. R. I. Pocock called the writer’s attention to this subject in 1903, since which time a careful watch has been kept on these animals, both in the open and in captivity. The captive individuals, it may be explained, were housed in what are known as “ McIntire cells”; that is to say, in little cases about three inches long, an inch or so broad, and a quarter of an inch or less high. The}body was of sheet-cork, the floor of glass covered with blotting-paper, and the roof of clear glass ; the whole being held together by rubber-bands. The glass forming the roof was transversely cut and hinged, so that food and moisture could be readily administered *. In these abodes the animals lived in health for a long time, and they were easily watched both under low powers of the microscope and with a lens. Observation was facilitated, it may be added, by the animals walking on the under surface of the roof, so as to expose to view the genital area, which occupies in this Order the usual position at the base of the abdomen, The sexes meet in ordinary walking position head to head, and, after some preliminary fencing, the male manages to grasp with one or both of the hands of the palps one or both of the hands of the palps of the female. Early observations showed this to be the case in Chelifer cimicoides Fabr.t, whose pairing, however, has not yet been fully made out. Similar behaviour was afterwards witnessed in the relatively gigantie Chelifer cyrneus L. Koch, and it was on this species that most of my observations were made. First of all, however, something must be said of Cheliter latreillii Leach, an animal subgenerically distinct from those just named and one of considerable interest in many respects. Il. Pairing of Chelifer latreillii Leach. Chelifer latreillii, always maritime in Britain, ranges with us from Fifeshire to Sussex, and is excessively abundant on the great sand-dunes of the coasts of Lincolnshire and Norfolk. In such places it makes its home for the most part in the tussocks of Ammophila arenaria; but it evidently moves about freely, being found often under pieces of wood, etc., on the sandy ground. It belongs to the subgenus Chelifer s. s., a small group * Cf. McIntire (4), pp. 71-2. + For the nomenclature employed in this paper, cf. Kew (18). 378 MR. H. WALLIS KEW ON THE remarkable for the specialization of the male, in which both primary and secondary characters are unusually pronounced*. The genital area of this sex is large and conspicuous, the first genital plate being short and of peculiar character, while the second is both long and broad, and under this latter are found two very large structures, inappropriately called ram’s-horn organs, to which it will be necessary to recur, ‘he fourth pair of coxe, which bound the genital area anteriorly, differ much from those of the female, being strongly concave behind and containing a peculiar organ, the coxal sac of With (18). Of characters remote from the genital area there is considerable diversity within the group; there are generally remarkable modifications in the legs of the first pair, and these modifications are unusually well-marked in the present species. ‘The whole leg is greatly strengthened, with hump-backed tarsus, and greatly enlarged claws, the anterior claw being of peculiar shape with oddly turned extremity and with a process along its anterior margin. Further, while the hand of the palp is a little smaller than that of the female, the fingers when closed at the tip have a wider gape. The ram’s-horn organs already mentioned—supposed to be tracheal in origin—have been studied in allied species by several authors. They are concealed under the second genital plate, where they he in a highly contracted condition. Preserved specimens, in exceptional cases, have them protruded externally ; and they have been figured thus protruded by Simon (6), and after him by Tomosvary (7); and by With (16). It does not appear, however, that they have been seen in action; and the suggestion of Menge (2) and Simon (6) that they are sper m-transmitters, perhaps intro- mittent organs tf, is erroneous, as also is that of Schtschelkanowzetf (17), who thought they might be concerned in placing sperm- masses on the ground. With regard to the other characters, except that With (14) and Schtschelkanowzeff (17) have supposed the coxal sac to be a sense- organ with some sexual significance, no suggestions appear to have been made. The gape of the fingers, however, is obviously con- nected with the grasping of hands already mentioned ; and the observations now recorded show what is done with the ram’s-horn organs and with the legs of the first pair. It was in May 1905, on the sand-dunes between Sandwich and Deal. that I first saw the weeting of the sexes of this animal. On turning over a piece of tin, I found on its under surface a male and female which had approached each other head to head, and were actively fencing with the palps. The male at length dis- armed the female by getting a firm grasp of the hands, which were held fast during the whole of these preliminary proceedings. * With (14), pp. 132-3; With (16), p. 220; Kew (18), p. 47. + Menge (2), 1D Wr, Tole in, ines; WB) Hansen (8), pl. vil. fig. 24; Croneberg (9), pp. 456- 7. pl. xia. figs. as AVP Bernard (LO), pp. 423-6 ; Oudemans (15), pp. 136-140; Schtschelkanowzeff veupy pp. 6-14. t¢ On the supposed occurrence of intromittent organs in this Order, cf. Lankester (12), p. 256; and Croneberg (9), p. 39. PAIRING OF PSEUDOSCORPIONES, 379 The animals moved considerably backwards and forwards and round about; and the male, all the time in a state of great activity, made at intervals determined advances towards the female, but he was prevented from approaching closely. On the occasion of each of these advances the male brought the ram’s- horn organs into action, running them out rather rapidly to their full extent ; they took at these times a forward lateral direction, their extremities usually assuming an outward curve and passing under or over the femora of the male’s palps. Occasionally they touched some part of the palps of the female, but this seemed accidental. At the full extension of the organs, the male vibrated his body in a peculiar manner and had at this time a remarkable, even villainous appearance ; but the organs were exposed only for a few moments, after which they ran in again rather rapidly, the male then taking a few steps backwards. Eventually the animals separated — perhaps disturbed by the sunlight to which they were exposed—without proceeding to any act of fertilization. In 1906, also in May, similar observations were made on specimens collected on the Lincolnshire coast, but again no act of fertilization was seen ; and no more observations were made till the spring of 1911. In the third week of April in that year, a good number of specinens were collected on the Camber sand-hills in Sussex ; and they were kept under daily observation in one of the cells above described. During the remaining days of April and the early days of May, the males, which had the abdomen rather full, seemed to have difficulty in restraining the ram’s-horn organs, the tips of which constantly appeared from under the great genital plate, which was at such times raised anteriorly and depressed into the abdomen posteriorly. Many fencing contests between male and female were seen; but the male did not always obtain any advantage in the grasp and was often in fact rather roughly used ; he continued, however, even at these times, to display the ram’s- horn organs with great energy. As before, I failed to observe the acts of fertilization. It was evident, however, that such acts had occurred, either before or after the animals came under observation, for about a month later eggs began to appear externally on a few of the females, and in the first week of July young broods appeared. Shortly before this time, fortunately, that is to say about mid-summer, there was a recurrence of sexual activity in the cell; and on 22nd June the whole process of the passing of the male product to the female was successfully witnessed. The animals, male and female, had taken up a position, ventral face uppermost, on the under surface of the glass; and the male, who was firmly holding both hands of the female, was making periodical advances towards her with display of the ram’s-horn organs as above described. It soon became evident that the female was offering but slight resistance; the male was allowed to make a near approach, and at length he was even permitted to caress with his chelicerze the chelicerze of the female. This done, he quickly retired as before by taking a step or two backwards; 380 MR. H. WALLIS KEW ON THE and it was now seen that as he did so the female was quite eager to take the corresponding steps forwards. As this tendency became more and more marked, the male released his grasp of the hands of the female, who was now free, at least from corporal Text-fig. 47. Chelifer latreillii Leach. Male and female; in ventral view, seen through a piece of glass, on the under-surface of which they are standing. ‘The position is that of the last phase of the court- ship; the male has released the hands of the female, and is about to extrude the spermatophore; the ram’s-horn organs are fully extended or nearly so. x 13. (The bristles and tactile-hairs are omitted.) control. The male continued, however, to make advances and to display the ram’s-horn organs even with greater energy than before; and finally, on the occasion of one of these advances—while PAIRING OF PSEUDOSCORPIONES. 381 not in contact with the female in any way—the ram’s-horn organs being fully extended (text-fig. 47), he extruded from the genital opening between the bases of these organs a large elongated structure—evidently a spermatophore *—one extremity of which became at once attached to the glass by means of a foot-like pad of quick-drying adhesive matter. The other extremity was still in contact with the genital opening of the male; and when thus freshly extruded this spermatophore bore externally, somewhat near the middle, some clouded liquid in the form of a moderately large surrounding globule. After a delay of a few moments, the male stepped backwards, and thus released the spermatophore, leaving it attached to the glass as just mentioned, but otherwise free, in an oblique position, with the unattached extremity directed towards the male. No sooner had the male thus stepped back, than the female came quickly forward till the female genital opening was in contact with the spermatophore. This forward movement of the female was accompanied, I believe, by a slight but rapid forward movement of the male; and, however this may be, the head of the male had passed under that of the female; and at the same moment, with great suddenness, the male threw forward the stout legs of the first pair and seized with them the anterior margin of the female genital opening, on which the enlarged peculiarly formed claws became firmly hooked ; and now the male commenced a rather long series of violent pulling movements with these legs, by means of which the body of the female was moved on the spermatophore, a part of which had, I believe, entered the female genital opening. These movements brought the proceedings to a close, and the animals now separated, leaving the sperma- tophore, or at least the shell of it, still attached by its foot to the glass. No repetition of these acts was observed. Another spermatophore was found in the cell, however, towards the end of August. Text-fig. 50 A (p. 386) shows the spermatophore from above and from below. It was of firm substance and somewhat complicated in structure. Beyond the foot of attachment it was rather slender but it gradually increased towards a neck-like constriction, beyond which was a widened head with a small horn-like point on either side ; and beyond this head was a rather long narrowed extremity of definite construction. The total length was considerably more than half that of the entire animal. III. Pairing of Chelifer cyrneus LZ. Koch. Chelifer cyrneus is known with us only in Sherwood Forest (Nottinghamshire) and Richmond Park (Surrey), where it lives under rather close-fitting bark of dead or partly dead oak-trees. * The occurrence, in this Order, of a spermatophore, though not mentioned in the text-books, is not entirely new, since McIntire (5) saw Chthonius @, in captivity, extrude elongated structures in which were spermatozoa. No female appears to have been associated with the male during this act, and it is thus doubtful whether the extrusion was normal. 382 MR. H. WALLIS KEW ON THE It belongs to the subgenus Chernes; and the male (text-fig. 48), in sharp contrast with that of Chelifer latreilli, is but little specialized. The genital area of this sex is only moderately con- spicuous, the second genital plate being short; the fourth pair of coxe differ only a little from those of the female, and there is no coxal sac; further, there are no protrusible ram’s-horn organs, and the legs of the first pair exhibit no marked modification. A slight enlargement of the hands of the palp, in fact, is the only secondary character of note. Text-fig. 48. Chelifer cyrneus Li. Koch. Male in ventral view. X 20. (The bristles and tactile-hairs are omitted.) Compared with Chelifer latreillii, the present animal is much larger and more heavily built, and unlike the former species, it is PAIRING OF PSEUDOSCORPIONES. 383 eyeless. In the male, in addition to the important differences above indicated, there is a deep-seated unlikeness in the internal organs; and we shall find that the spermatophores are entirely unlike, with corresponding differences in the pairing. In the second week of April 1911, a supply of specimens was obtained from Richmond Park *, and a cell was stocked with five or six individuals, which were kept under daily observation tiil the beginning of the second week of May. During this time, fortunately, abundant opportunities were afforded for observing the pairing, which was carried on with great persistence on ati least eight occasions. The animals did not walk easily on the under surface of the glass, and pairing was not observed in that position ; it was well seen, however, both in dorsal and lateral view, and under the latter condition the details of the process were distinctly made out. The male and female met, as already stated, in walking position head to head (text-fig. 49, p. 384); and, as in the former species, they engaged in some preliminary fencing with the palps. During this fencing the male always obtained with one of the hands a firm grasp of one of the hands of the female; and, con- trary to what occurred in the former species, this grasp was always maintained throughout, that is to say until the animals parted company when the pairing for the time being was complete. Moreover, while the former species held the female with both hands, the present animal invariably employed one hand only in this way, always keeping the other hand free. After the grasp was made, the animals fenced with the free palp and moved about a little backwards and forwards; the male— all the time alert and eager—constantly attempting to approach closely to the female. Wate hing the animals carefully at this time, it was soon observed that the fencing had given place to a regular system of display on the part of the male, whose actions in this respect were quite unlike anything seen in the former species. In the present case—in the absence of ram’s-horn organs—the display was made with the free palp and with the legs of the first pair. The free palp was brought round at frequent intervals and the great hand rapidly shaken in the face of the female in a remarkable threatening or perhaps beckoning manner; and the first legs were rapidly “moved, that is to say lifted and replaced, in most peculiar fashion. After a time the female, apparently much impressed with these actions, offered little or no resistance, the male having now no difficulty in approaching closely. At length the male—head to head with the female but not in contact ‘except for the continuous grasp of one hand—deflected the base of the abdomen to the floorand atlixed there the adhesive foot-like attachment of the spermatophore. Almost immediately, the body was raised to its normal position, * The writer is indebted to His Majesty’s Office of Works and to Mr. S. Pullman, the Superintendent of the Park, for the permission and facilities necessary for the taking of the animals in this place. MR. Hf. WALLIS KEW ON THE 384 (“Po}FIULO a1B S.BY{-a]1JOv} OY} pus ‘sopzsIIq OY} ‘O[VULOZ OY] JO EpIs FYSII at]3 Jo pu jeu at} Jo apis }Jo] ol} Jo sasepuaddy oy 7) “BULIOdS Ot} SUTATODAL B]BULAT °C ‘atoydoyeutsods 944 04 Spava.1OJ SULMMOD o[BUEJ ‘SpABM Youd SULAGEA oe “G ‘atoydozeursods payayduroo YIM epeurt Lq pozuosjzuoo opeuegy “W OL X “Yoo ry snawtha wafyayp jo surmeg ‘6p SY-7X0], PAIRING OF PSEUDOSCORPIONES. 385 and one then saw that a whitish filament was stretched from the foot-like attachment to the genital opening ; ; and now the male produced very quickly from the genital opening a large globule of brilliant liquid; and this globule remained on the filament, just below the genital opening, like a great bead on a thread. Standing thus for some moments, perhaps awaiting some sign from the female, and continuing with great energy the shaking of the free hand, the male at last quickly raised his body and took a step or two backwards so as to free the globule and filament ; and it was now seen that the filament, which passed through the globule, bore just above it a small irregular termination of whitish substance. The remarkable spermatophore thus com- pleted remained standing on the ground in an erect or suberect position. At the moment when the male raised bis body and stepped back, the female, still held by the hand by the male, ran forward; the movement of the two animals being per fectly mutual and just sufficient to bring the genital area of ‘the female into the exact position occupied “the moment before by that of the male. As the female thus ran forward the genital orifice was widely open; and just as the spermatophore was reached a slight forward and downward movement was made upon it; and, the genital orifice being quickly closed, the globule together with the whitish termination of the filament were taken in at a gulp. Only the naked filament remained. At the moment of this rapid gulping in, the female drew back ; and at the same moment the male, with great eagerness and with the chelicere extended and open, ran forward until the fore parts of male and female were in contact; and the two animals remained thus in a state of quiescent embrace for some time. During this embrace the head of the male went under that of the female; but no part of the male was at any time directed towards the female genital opening. The coupling action of the legs of the first pair, which appears to be an essential condition in the pairing of Chelifer latreillii, had no counterpart in the present species. At the conclusion of this period of repose, the male roused himself to activity again, recommenced the rapid movements of the free palp and of the legs of the first pair, and the whole process was repeated. ‘The whole process was, in fact, always repeated many times. To this there was no exception in all the observations. The male never once released, not even during the periods of repose, the fixed grasp of the hand of the female; spermatophores were regularly produced and received at intervals of from eight to ten minutes; and this recurrent pairing was continued for two hours, or even for three hours, or more. By the beginning of the second week of May the activity of the males showed signs of abating, and the colony was broken up. Soon afterwards, however, a new colony was established, and pairing was seen again in 5 uly and August. Text-fig. 50 B shows the spermatophore—two of eae tale lateral view. This object agrees with that of the former species in its attachment to the floor, but is otherwise of different character, Proc. Zoot, Soc,—1912, No. XXV. 25 386 MR. H. WALLIS KEW ON THE being altogether more simple and smaller. Beyond the small foot of attachment it consists, as we have seen, merely of asimple, more or less rigid filament, which bears around it near the top a large globule of liquid and has just above the globule an irregular termination of whitish substance. Text-fig. 50. — Y Ne A. Spermatophore of Chelifer latreillii Leach, from above and from below. X 50. B. Spermatophores of Chelifer eyrneus L. Koch, from the side. X 50. C. Spermatozoa of Chelifer cyrneus 1. Koch. (Drawing commu- nicated to the writer by Mr. C. J. With.) The globule has a diameter somewhat exceeding the depth of the tibia of the legs of the animals. Unfortunately it was not ascertained whether the spermatozoa (text-fig. 50 C) were contained in the globule or above it at the termination of the filament— from my experience in this direction the obtaining of a com- plete spermatophore for examination will not be an easy task— but however this may be, the amount of material transferred from the male to the female is surprisingly large. PAIRING OF PSEUDOSCORPIONES, 387 On the breaking up of the first colony, the animals were despatched to Mr. ©. J. With of Copenhagen, who obligingly examined them, and found spermatozoa in the females. These formed a mass in the vagina ; and occurred also, placed in a single row, in the two long narrow irregularly-coiled tubes which run out from the vagina anteriorly. These tubes were figured in an allied species by Croneberg (9). From their structure, and from the presence of spermatozoa which would evidently be preserved there, they must be regarded as receptacula seminis, not as glands as Croneberg supposed *. It was on the present species that Schtschelkanowzeff (17) made the already published observations to which reference is made at the commencement of this paper t. He found the animal in the Russian Government of Tschernigoff, in a forest belonging to his father, where certain pine-stumps were reserved for the purposes of observation. By removing the bark from these stumps he was able to learn much of the animal’s manner of life, and frequently saw their pairing. He relates that after the grasping of one hand and other preliminaries, the male made some convulsive movements and depressed the abdomen to the stump ; and thereupon the female took the place of the male and depressed her abdomen exactly at the spot where the male had done so; and these actions were repeated several times. The male, he concluded, had deposited sperm and the female had taken it up; and on subsequent dissection of the female, sperma- tozoa were detected in the vagina and receptacula seminis. This impression of the pairing, it will be seen, is roughly in agreement with the account above given; it is, in fact, exactly what would be obtained by a not very close observation of the animals in dorsal view, in the open, with or without a lens. Presumably they were not viewed laterally, for the sperm’ was supposed to have been deposited in little heaps ; and thus there is no mention of the characteristic spermatophore. Schtschelkanowzeff supposed, finally, that the active rdle was taken throughout by the female; but in this, doubtless, he was mistaken. IV. Summary. The two Pseudoscorpiones observed belong to the genus Chelifer s.1., and represent respectively the subgenera Chelifer s.s. and Chernes. The males are differently equipped : the Chelifer has an elaborate genital area, long ram’s-horn organs, and much modified legs of the first pair; the Chernes has a less elaborate genital area, no ram’s-horn organs, and no modified legs. There is agreement, * This result appears to have been arrived at already by Schtschelkanowzeff (17, p. 27), and ef. Lubbock (3, p. 615). + Schtschelkanowzeff (11) described his animal as C. multidentatus, Sp. n.3 but paratypes obligingly communicated to the writer establish its identity with C. cyrneus. 25* © 388 MR. H. WALLIS KEW ON THE however, in a feature of prime importance: both are destitute of intromittent organs of copulation. Fertilization is effected in both by means of a spermatophore. This structure in the Chelifer is large and somewhat compli- cated ; in the Chernes relatively small and merely filiform Correlated with the differences im equipment and in the spermatophore are considerable differences in the pairing. There is agreement, however, as follows. The male and female face one another in walking position. ‘The male grasps with one or both hands one or both hands of the female. There is a forced courtship, during which the male makes display of definite character. At length he extrudes the spermatophore, which is attached to the floor in front of the female, where it stands erect or obliquely. From this object the male retires backwards, and the female at the same moment comes forwards. The movement is just sufficient to bring the female genital opening into contact with the spermatophore, and the male product is thus received without delay. The differences may thus be stated. The Chelifer male holds the female with both hands; and makes display with the ram’s- horn organs. He releases the hands previously to the extrusion of the spermatophore. When the female comes forward, he seizes her by the genital opening with the legs of the first pair, and then executes a series of pulling movements by which presumably the reception of the male product is facilitated. The animals now separate; and it is unlikely that the process is repeated, except perhaps at long intervals. The Chernes male holds the female with one hand only. He makes his display with the other hand and with the legs of the first pair. He does not release the female previously to the extrusion of the spermatophore, but continues to hold her by the nand throughout. When the female reaches the spermatophore, she takes the male product quickly and retires backwards. There is no seizing of the genital opening by the male. As the female retires, however, the male quickly follows; and there is a period of repose; after which the whole process is repeated. Moreover, it is repeated, with similar periods of repose, many times; and a large number of spermatophores are thus produced and received in rather quick succession. By way of conclusion it may be recalled that the genus Ohelifer s.1. comprises, in addition to the subgenera Chelifer s.s and Chernes, two others, Alemnus and Withius : ali distinguished by remarkabie differences in the sexual equipment of the males— even within the subgenera there are striking divergences in the secondary characters ; and these facts, in view of the differences above noted, certainly lead one to expect great variations in the pairing processes. A review of the males of the whole Order, moreover, serves greatly to increase this expectation—one may refer for instance to the complete dissimilarity in the genital areas of Obisium and Chihonius—so that there is here undoubtedly PAIRING OF PSHVDOSCORPIONES. 389 a fertile field for investigation. Nevertheless it may perhaps be predicted that the general lines now indicated are those on which fertilization will be found to be effected in all Pseudoscorpiones. V. List of References. (1) Rost von Rosgnnor, A. J.-—Der monatlich-herausgegebenen Insecten-Belustigung, iii. Niirnberg, 1747-1755. (2) Mencr, A.— Ueber die Scheerenspinnen, Chernetide. Neueste Schriften d. Naturforschenden Gesellschaft, v. pp. 1-42, pls. i-v. Danzig, 1855. (3) Lussockx, J.—Notes on the Generative Organs and on the Formation of the Egg in the Annulosa. Philosophical Transactions of the Royal Society, cli. pp. 595-627. London, 1862. (4) McIntire, 8. J.—Some cheap aids to Microscopical Studies. Journal Quekett Microscopical Club, i. pp. 69-72. London 1868. (5) McIntire, S. J.—Pseudoscorpions. Hardwicke’s Science- Gossip, v. pp. 243-247. London, 1869. (6) Stmon, E.—Les Arachnides de France, vii. Paris, 1879. ? (7) TomosvAry, O.— Pseudoscorpiones Faune Hungarice. Magyar Tudomanyos Akad. Math. és Természettud, Kozlemények, xviii. pp. 135-256, pls. i-v. Budapest, 1882. CRONEBERG, A.—Beitrag zur Kenntniss des Baues der Pseudoscorpione. Bull. Soc. Imp. des Naturalistes (n. s.), i. pp. 416-461, pls. x.—xi. a. Moscou, 1888. (1G) Bernarp, H. M.—Notes on the Chernetide, with special reference to the Vestigial Stigmata and to a new form of Trachea. Journ. Linn. Soc., Zoology, xxiv. pp. 410-430, pls. xxxi-xxxi. London, 1894. (11) ScurscHELKanowzerr, J. P.—Chernes multidentatus, n. sp., nebst einem Beitrige zur Systematik der Chernes-Arten. Zoologischer Anzeiger, xxv. pp. 350-355. Leipzig, 1902. (12) Lankester, EK. R.—The Structure and Classification of the Arachnida, Quart. Journ. Microscopical Science (n. s.), xlvili. pp. 165-269. London, 1904. (13) Wir, C. J.—On Chelonethi, chiefly from the Australian Region, in the Collection of the British Museum, with Observations on the ‘ Coxal sac” and on some cases of Abnormal Segmentation.. Ann. & Mag. Nat. Hist. (7) xv. pp. 94-143. London, 1905. (14) Wirx, C. J.—The Danish Expedition to Siam, 1899-1900. Chelonethi: an account of the Indian False-Scorpions together with studies on the anatomy and classification of the Order. Kgl. Danske Videnskabernes Selskabs Skrifter (7), i. pp. 1-214. Copenhagen, 1906, (8) Hansen, H. J.—Zoologia Danica, iv. Copenhagen, 1885. 390 MR. OLDFIELD THOMAS ON (15) Oupemans, A. C.—Ueber Genitaltracheen bei Chernetiden und Acari. Zoologischer Anzeiger, xxx. pp. 135-140. Leipzig, 1906. (16) Wir, C. J.—An Account of the South American Chell- ferine in the Collections of the British and Copenhagen Museums. Trans. Zool. Soc. xvill. pp. 217-340, pls. xxix.— xxxl. London, 1908. (17) ScutscHELKANOowzEFF, J. P.—Der Bau der miannlichen Geschlechtsorgane von Chelifer und Chernes. Festschrift zum sechzigsten Geburtstage Richard Hertwigs, i. pp. 1-38. Jena, 1910. (18) Kew, H. W.—A Synopsis of the False-Scorpions of Britain and Ireland. Proc. Royal Ivish Academy, xxix. B. pp. 38-64, pls. iv—vi. Dublin, 1911. (19) Pocock, R. 1—A Monograph of the Terrestrial Carboni- ferous Arachnida of Great Britain. (Palsontographical Society.) London, 1911. EXHIBITIONS AND NOTICES. February 20, 1912. Dr. A. Suir Woopwarp, F.R.S., Vice-President, in the Chair. Dr. A. T. Masterman, M.A., F.Z.8., gave a demonstration, illustrated by a large number of lantern-slides, of recent imvesti- gations on Age-determination in the Scales of Salmonoids, with special reference to Wye Salmon. March 5, 1912. Sir Joun Rose Braprorp, M.D., D.Sc., F.R.S., Vice-President, in the Chair. The Races of the European Wild Swine*. Mr. Ouprietp Tuomas, F.R.S., F.Z.8., exhibited the skull of a Hungarian Wild Boar, recently presented to the National Museum by Fraulein Sarolta von Wertheimstein, and that of an ordinary German Wild Boar, representing the typical Sus scrofa Linn. * [The complete account of the new forms described in this paper is given here, but since the names and preliminary diagnoses were published in the * Abstract,’ they are distinguished by being underlined.—EpirTor. | EUROPEAN WILD SWINE. 391 The difference in size between these two skulls was so enormous that Mr. Thomas expressed the opinion that the Hungarian Boar should be distinguished as a diflerent species, which he proposed to call Sus attila. A fine stuffed specimen of the same species, from Volhynia, 8. Russia, presented by Count Potocki, had been on exhibition for some years in the Museum, under the old name of Sus scrofa. The difference between the two species was mainly in size, as would appear from the skull-measurements given below; but it might be noticed that both specimens of Sus attila were, on the whole, lighter in colour, and had whiter muzzles, than the available specimens of Sus scrofa. No series of skins, however, was available to show how far these colour-differences were constant. The character of the pelage of Sus attila was similar to that of S. scrofa in the presence of a thick woolly underfur. The median anterior hoofs in Sus attila were 65 mm. in length, as compared with 48 mm. in S. scrofa. The type locality of S. attila was Kolozsvar (= Klausenburg), Transylvania, and the species no doubt extended through Russia into Siberia. The other names usually placed in the synonymy of Sus scrofa— selosus Boddaert, aper Boddaert, ewropeus Palas, and celtica Strobel —were all merely suggested alternatives for scrofa, and applied solely to the German Wild Boar, this being the typical form of Linneus’s species *. Furthermore, Mr. Thomas pointed out that the Wild Boar of Southern Spain was, on the other hand, so very much smaller than the true Sus scrofa of Germany that it appeared worthy of a special subspecific name, and he proposed to call it Sus scrofa beticus. In addition to its small size, the two skins in the British Museum (both of winter specimens) were remarkable for having no woolly underfur whatever, that of Sus scrofa scrofa being thick and abundant. A female specimen of this small Wild Boar, from Seville, had been presented to the Museum by the late Lord Lilford in 1895, and a male skin and skull, and a separate skull, from the Coto Dofiana, by Mr. Abel Chapman in 1908. Finally, the Wild Boar of Nor oe n Spain was intermediate in size between S. s. beeticus and S. s. scrofa, and possessed, at least in winter, a woolly underfur as in teadinsy Wild Boars. Of this form a fine male and female had been obtained for the Museum by the Rev. Saturio Gonzalez at Quintanar de la Sierra near Burgos. Mr. Thomas proposed to call this race, whose skull-measure- ments were included in the table below, Sws scrofa castilianus. The following were the skull-dimensions in millimetres of (1) the type of S. aétila, an adult but not old male, (2) of a rather * Cf. Thomas, P.Z.5. 1911, p. 140. Bi) ON EUROPEAN WILD SWINE. older male of Sus scrofa from Baden, Germany, (3) of the type skull of S. s. castilianus, and (4) that of S. s. beticus, intermediate in age between the first two :— Sus scrofa Sus scrofa Sus scrofa Sus attila. scrofa. castilianus™. beticus. 3: 3. 3. 3. Occipito-nasal length ............... 452 385 353 324, Condylo-basal length ............... 407 (c.) 3855 335 (c.) 305 Zygomatic breadth .................. 174 146 135 142 Interorbital breadth .................. 102 73) 78 72 IWeyalls, WOVEN asbseensvscancdcaraseuce 250 208 189 173 weiperapy)| ORG evo fn ORive eamn aetna 53 36 30 33 Median occipital height ............ 159 ae 114 Bs f > skull on lower jaw rere: ate e AA 271 208 198 208 Height at anteorbital foramen ... 84. 65 60 61 Upper cheek-tooth series ............ 134 121 125 117 Lower molar series .........,........ 84 69 79 72 Breadth of antero-internal face of WOWIEE CAA® sjoshysosncooee Woo setae 25°5 215 23 20 IWS» Seacrest Aya ue ae ere Mcaconre sche tania AKO) Seo Pig 35X21 43 X 22 35°5 X21 Ve ees Aa o's ase us setaet ernst a pL LO, 36X17 42175 36 X17 The results arrived at were as follows :— 1. Sus scrora Linn. Upper length of skull not exceeding about 410 mm.; height, including lower jaw, at most 210 mm, Subspecies :— ] A. SUS SCROFA SCROFA. Synn. sefosus, aper, ewropeus, celtica. Upper length of skull of male about 380-410mm, Woolly underfur present. Range, Central Europe, from Germany to the Pyrenees. Type locality, Germany. 1 B. SUS SCROFA CASTILIANUS. Thos, Abstract P. Z.8, 1912, p. 13 (March 12). Upper length of skull of male 353 mm., of female 331. Underfur present. Range. Northern Spain. Type locality. Quintanar de la Sierra, near Burgos. Type. Adult male. B.M. No. 11,10.5.3. Collected by Rev. -Saturio Gonzalez; presented by the Hon. N, Charles Roth- sehild. * An old female skull of 8. s, castilianus measured 331 mm. in occipito-nasal length, ON SWISS SPIDERS. 393 1c. Sus SCROFA BATICUS. Thos. Abstract P. Z.S. 1912, p. 14 (March 12). Upper length of skull of male 324 mm. No woolly underfur present, even in winter. Range. Southern Spain. Type locality. Coto Dofiana, Huelva. Type. Old male. B.M. No. 8.3.8.12. Collected 6 February, 1908, and presented by Abel Chapman, Esq. 2. Sus ATTILA. Thos. Abstract P. Z. S. 1912, p. 13 (March 12). Upper length of skull of male 452 mm.; height, including lower jaw, 271 mm. Woolly underfur present. Range. Hungary and 8. Russia, probably extending into Siberia. Type locality. Kolozsvar (= Klausenburg), Transylvania. Type. Adult male. B.M. No. 12.1.23.1. Collected 8th Decem- ber, 1911. Presented by Friiulein Sarolta von Wertheimstein. PAPERS. 21. A Contribution towards the Knowledge of the Spiders and other Arachnids of Switzerland. By the Rev. O. Pickarp-CamBripcE, M.A., F.R.S., C.M.Z.S8., etc. [Received October 13, 1911: Read February 20, 1912.] (Text-figures 51 & 52.) The materials for the accompanying List have been kindly got together for me by those whose initials are appended to each species. They have been collected for the most part during tours through Switzerland, and in one or two cases during short sojourns in some of the localities mentioned. It is not pretended that the number of species enumerated represents more than a small proportion* of those recorded by other authors, or likely to be found by careful expert search in Swiss regions, but it shows how very many objects in one special branch of Natural History can be obtained even by observers who may be non-specialists, as was the case with nearly all those whose initials are here appended. Of course it must be taken into consideration that in the collect- ing of Arachnids there is no necessity for the paraphernaha absolutely required for the collecting and preserving of entomo- logical specimens in general. A few small bottles of methylated * The present known number of Swiss Spiders, according to Dr. Roger de Lessert, amounts to 616, See Revue Suisse Zool, vol. xvi. p. 485, 1909. 394 THE REY. O. PICKARD-CAMBRIDGE ON spirit of wine, a few glass tubes of different sizes, contained in strong conveniently shaped tin boxes, are really all the materials that are needed for the preservation of Arachnids; while the ‘“‘eye of faith and the finger of instinct” assisted by an empty glass tube will suffice in the actual field. Not, of course, but that a Strong entomological sweeping hoop-net, for the brushing and sweeping of shrubs and herbage, would fill the pocket-bottles all the faster, and probably with some species not obtainable by other methods. The preponderance in the following List of these groups of Spiders which at once and most obviously claim the attention of the tourist as he toils along—viz., the Hpeiride, Thomiside, Lycoside, and Salticidee—shows, it seems to me, how rich a harvest would be reaped by a resident specialist in some of the localities. The number of species here recorded, in these four groups alone, amounts to 102 out of the total of 212 species collected of the Araneidea (or true Spiders); while those of the great group Theridiide (in its widest sense) are only 65 in number: a group which, I may remark in passing, numbers 1 the British Islands alone upwards of 250 out of a total of the whole Order of somewhere about 550! The greater number, however, of the Theridiide require something more in the way of wearisome search than even the most observant eye of the ordinary passing tourist; and hence the tourist’s bottle is most commonly filled by species of the other four groups mentioned, and which, often in countless numbers, are obvious on all sides on a fine day in the mountains. I must here acknowledge my indebtedness to Mons. Kugéne Simon of Paris,and Dr. Roger de Lessert, of the Natural History Museum, Geneva, for their invaluable assistance in the identifica- tion of many of the species in the following List with which I was unacquainted. List oF Swiss ARACHNIDS. Collected, or sent to me, at various periods and in various o) ’ p localities by the following :— Initials in List. A.W.P.-C. (A. W. Pickard-Cambridge, Balliol College, Oxford.) R.J.P.-C. (Rev. R. J. Pickard-Cambridge, Warmwell Rectory, Dorchester.) H.A.P. (Jate Rev. H. A. Pickard, Airedale, Oxford.) C.W. (Cecil Warburton, Christ’s College, Cambridge.) F.P.S. (fF. P. Smith, 5 Gibson Square, London.) R.G. (Robert Godfrey, late of 46 Cumberland Street, Edinburgh.) G.N. (late George Nicholson, Director, Royal Gardens, Kew, and 37 Larkfield Road, Richmond.) A.S.A. (late A. 8. Atkinson, Nelson, New Zealand.) SWISS SPIDERS. 395 Lnitials in List. E.S. (Eugéne Simon, 16 Villa Said, Avenue du bois de Boulogne, Paris.) A.E.E. (Rev. A. E. Eaton, Symondsbury, Bridport, Dorset.) H.S8. (Henry Speyer, Reigate.) R.deL. (Dr. Roger de Lessert, Museum of Natural History, Geneva.) C.E.M.I. (C.K. M. Ince, per late F. O. Pickard-Cambridge.) CU. (Dr. Collingwood, the late.) Class ARACHNIDA. Order ARANEIDEA. Fam. DYSDERID 2. Harpactes drassoides Sim. Chamounix. R. J. P.-C. Segestria senoculata Linn. Simplon. A.S. A. Fam. DRASSIDA. Drassus hispanus L. Koch. Sulden-Tyrol. A. W. P.-C. troglodytes C. Li. Koch. Zinal, Engstlen Alp, and Chalet de Meléze, St. Gervais les Bains. A. W. P.-C. Simplon. A.S. A. Zermatt. R. J. P.-C. Switzerland. G. N. Drassodes lapidosus Walck. Simplon. A.S.A. Switzerland. H.S. Chamounix, R.J.P.-C. St. Gervais les Bains. A. W.P.-C. Montreux. C. % pubescens Thor. Arolla. A. W. P.-C. Prosthesima apricorum L. Koch. Simplon. A.S8. A. Es talpina L. Koch. Bel Alp. G.N. ms petiwerti Scop. Montreux. C. a nigrita Fabr. Chalet de Meléze, St. Gervais les Bains. A. W. P.-C, ) latreillii Sim. St. Gervais les Bains. A. W. P.-C. o prefica L. Koch. “Switzerland.” H.S. Callilepis nocturna Linn. St. Gervais les Bains. A. W. P.-C. Simplon, A.S.A. Switzerland. H.8. Gnaphosa badia L. Koch. (@. molesta Cambr.) St. Gervais les Bains, Arolla, and Sulden-Tyrol. AW Pe. + petrobia L. Koch. Switzerland. G. N.and R. J. P.-C. o tigring Sim. Switzerland. R.J. P.-C. Micaria hospes Kulez. Simplon. A.S. A. » breviuscula Sim. Zermatt. R. J. P.-C. scenica Sim. Bel Alp. G.N. Zermatt. R. J. P.-C. 9 ? Zinal. A. W. P.-C. » pulicaria Sund, St, Gervais les Bains. A. W. P.-C. 396 THE REY. 0. PICKARD-CAMBRIDGE ON Clubiona hilaris Sim. Simplon. A.S. A. Cheiracanthium italicum Can. & Pav. Zermatt. H.8. Zora maculata Bl. Chamounix. A. W.P.-C. Montreux. C. Fam. DICTYNIDSE. Dictyna viridissima Walck. Alps. H.5. » jlavescens Walck. Alps. E.S. 4 uncinata Westr. Switzerland. H.§. Amaurobius fenestralis Stroem. Simplon, A.S. A. Zinal. A.W.P.-C. Montreux. C. a jferox Walck. Montreux. C. _ 4-guttatus Hahn. Alps. E. 5. Fam. AGELENID. Crypheca silvicola C. L. Koch, Zinal. A. W. P.-C. Celotes terrestris Wid. Switzerland. R.G. and A. W. P.C, Interlaken. A. EK. EH. » pickardii Cambr. Switzerland. H.A. P. » atropos Walck. Chamounix. A. W. P.-C. Switzerland. H.S8. , Claustrarius Hahn. Switzerland. R.G., A. H.-E., R.J.P.-C., and G.N. Tegenaria campestris C. L. Koch. Alps. E.S. i; tridentina L. Koch. Simplon. A.S. A. a derhamii Scop. Montreux. C. ‘ pusilla Sim. Chamounix. A. W. P.-C. He domestica Clk. Montreux. C. Cicurina cinerea Panz. Switzerland. R.G. Textrix denticulata Oliv. Simplon. A.S.A. Bel Alp. G.N. Montreux. C. Agelena labyrinthica Clk. Simplon. A.S. A. Switzerland. H.5., R.J. P.-C.,and H. A. P. Montreux. C. Fam. ZODARIIDS. Zodarion gallicum Sim. Alps. H.S. Fam. PHOLCID &. Pholeus phalangioides Fuess. Montreux. C. Fam. THERIDIID&. EH pisinus truncatus Walck. Montreux. C. Theridion riparium Bl. Switzerland. R.G. + bigibbum, sp. n. (text-fig. 51). Alps. H.8. (For description see appendix, p. 403.) SWISS SPIDERS. 397 Theridion sisyphium Clk, Simplon. A.S.A. Zinal and Engstlen Alp. A. W.P.-C. Switzerland. H.8. and H.A.P. Montreux. C. * nigro-variegatum Sim. Geneva. R. de L. i. nigro-punctatum Lae. Alps. ELS. * blackwallii Cambr. Alps. E.S. Phyllonethis lineata Clk. Switzerland. H. A. P. Dipena braccata C. L. Koch. Alps. E.S. Steatoda bipunctata Linn. Simplon. A.§8. A. Lithyphantes corollatus Linn. Alps. E.8. HY paykullianus Clk. Alps. ELS. Teutana grossa C. L. Koch. Alps. ES. Vuryopis flavomaculata C. L. Koch. Alps. E.S8. Asagena phalerata Panz. Alps. E.S. Switzerland. G.N. Chamounix. A. W. P.-C. Enoplognatha thoracica Wid. Alps. B.S. Robertus lividus Bl. Simplon. A.S. A. Arolla. A. W. P.-C. Tapinopa longidens Wid. Alps. E.8. Bolyphantes alticeps Sund, St. Gervais les Bains. A. W. P.-C. Drapetisca socialis Sund. Switzerland. C. E. M. I. Linyphia marginata C. L. Koch. Switzerland. G.N. » triangularis Clk. Alps. E.8. Montreux. C. » parygiana C. L. Koch. Alps. ELS. » montana Clk. Simplon. A.S.A. Switzerland. H. A. P. » pusilla Sund. St. Gervais les Bains. A. W. P.-C. » frutetorum C. L. Koch. Alps. E.S. » emphana Walck. Alps. E.S. hortensis Sund. Alps. E.S. Leptyphantes tenuis Bl. St. Gervais les Bains. C Le) \ pS me lp < /9 4 Vo ge P i te | A are 0 aes te ® ; ® < Re > a R é. a BLOOD PARASITES. P:Z)8. 1912. FIA EIN. - a - ihe g® Ge Yaa We y : - Cbatlewws Ge » Gea, WE we Ay n SORA ee bes AQP 0. Pe ¢@ J Ogg 8 741 t 4 a é . & a a BLOOD PARASITES. b P:Z.S: (9122P1 EV. Tos 5 (Os LEG - ‘ ras (o°2") maith es Fe ; 4 Sok oy CRE BN ae ste Soo Pt ee) a ee Ng EOS mer SRS a PS od BLOOD PARASITES. BLOOD-PARASITES, ; 407 in the Gardens belong to the two great groups of the Protozoa and the Worms, and, as regards the elements of the blood, they are either extra-corpuscular or intra-corpuscular, I will begin with the extra-corpuscular parasites, those which live in the serum, and these are the nematode worms, the spiro- chetes, the trypanosomes, and other flagellates, Firstly, the nematode worms —they all belong to the class Filaria. The embryos only are found in the blood, as the adult filarie could not pass through the capillaries. These microfilarie are the least harmful to their hosts of any of the blood-parasites, and all the pathological effects we know of filarize are due to the adult worms, which have been found only in a very small pro- portion of the cases here. The embryos are generally surrounded by a fine capsule, which is cast off when they enter into the body of the mosquito, when their further development takes place. I have found microfilarie in the blood of 15 mammals of 13 different species, in 101 birds of 74 different species, and in 13 reptiles of 5 different species; and filarie have not been found before in 88 out of these 92 species of animals, and are new, at any rate as regards hosts. The animals in which they have been found have come from all parts of the world, the largest number from the Americas, but the following list will show how wide-spread the infection is. Emeryo FInarLe rounD IN tHE BLooD OF MAMMALS. (All are either new hosts or new parasites, or both, except those marked with an asterisk.) Name. HaAprrar. Tyre or Frnaria. Suricate (Suricata suricatta) .......... S. Africa. Long. Black-handed Spider Monkey (Ateles C. America. Long. geoffroyi). Black-headed Lemur (Lemur mungos). Madagascar, Long and slender. Crowned Lemur (Lemur coronatus)... do. Very long, striated. White-fronted Capuchin (Cebus Ecuador. Medium, thick. albifrons). Golden Cat (Felis temmincki) ......... Sumatra. Long. Bridled Wallaby (Onychogale fre- N.S. Wales. Long. nata). Rat-tailed Opossum (Didelphys nudi- S. America. Medium. caudata). Collared Peceary (Tayassu tajacu) ... do. Long. 3 Pinche Marmosets (Leontocebus Colombia. Long. edipus). Lion Marmoset (Leontocebus rosalia). Brazil. Long. Javan Chevrotain (Tragulus Java. Long. Javanicus). Ant-eater (Myrmecophaga tridactyla) S. America, Medium. Birps, Himalayan Whistling Thrush (Myio- N. India. Short. phoneus temmincki). Lanceolated Jay (Garrulus lancco- do, Short. latus). 408 Birps (continued). NAME. Hasirar. Spotted Emerald Tanager (Calliste guttata). 2 Great-billed Touracous (Turacus macrorhynchus). Wood-Thrush (Lurdus mustelinus)... S. America. W. Africa. N. America. *3 Blue-faced Honey-eaters (Hntomyza Australia. cyanotis), Sooty Crow Shrike (Strepera fuli- do. ginosa). *2 Black-backed Piping Crows (Gymno- do. rhina tibicen). Ultramarine Jay (Aphelocoma ultra- Mexico. marina). Stanley Parrakeet (Platycercus W. Australia. icterotis). Black -headed Cat-Bird (4@lurcedus melanocephalus). New Guinea. 6 King Birds of Paradise (Cicinnurus do. regius). 4 Lawes’ Birds of Paradise (Parotia do. lawesi). 2 Count Raggi’s Birds of Paradise do. (Paradisea raggiana). Red-winged Francolin (Francolinus gariepensis). Common Cow-Bird (Molothrus pecoris.) N. America. 2 Orange-cheeked Waxbills (Hstrelda W. Africa. melpoda). Red-backed Shrike (Lanius collwrio). Banded Aracari (Péteroglossus tor- S. Africa. Europe. C, America. quatus). Cuban Mocking Thrush (Mimocichla N. America. rubripes). Crimson-eared Waxbill (Hstrelda W. Africa. pheenicotis). Black-crested Cardinal (Gubernatrix S. America. cristata). Violet Manucode (Phonygama chaly- New Guinea. beata). Fire-red Finch (Spermophila minuta). Venezuela. American Robin (Turdus migratorius) N. America. Red-capped Parrot (Pionopsittacus Brazil. pileatus). White-bellied Plumed Dove (Lopho- phaps leucogaster). Orange-headed Thrush (Geocichla citrina). 2 Violet Tanagers (Huphonia violacea) Blue-winged Tanager (Calliste cy- anoptera). Whydah Bird (Urobrachya albonotata) 8. Africa. India. C. America. S. America. *Garrulous Honey-eater (Myzantha Australia. garrula). 2 Brazilian Hangnests (Icterus Brazil. jamaicai). 2 Jay Thrushes (Garrulaax leuco- N. India. lophus). MR, H. G. PLIMMER ON N. Australia. TYPE. Short, thick. Short, straight. do. Short, thick. Long, edges serrated. Short, straight. Short, thin. Short, straight. Short, thick. Very short, thick. 2 kinds: one long and thick, the other short. Short. Small. Short. Medium. Long. Short, straight. do. Very long. Short. 2 kinds: one long and one short. Long. Long. Short, thick. Long. 2 kinds: one long and one short. Medium, thick. Long. Long. Short. Long, thick. Medium. NAME. 6 Green-billed Toucans (Ramphastos dicolorus). BLOOD-PARASITES., Grass Finch (Hrythrura prasina) ... Baillon’s Avacari (Andigena bailloni) Fire Finch (Lagonosticta senegala). Blue-cheeked Barbet asiatica). Shama (Ciétocinela macrura) Dial Bird (Copsychus saularis) (Megalema White-collared Ouzel (Merula albo- cincta). Song Sparrow (Melospiza pusilla) ... Cat-Bird ( Gialeoscoptes carolinensis). Orange Weaver- Bird (Huplectes Sranciseana). Beautiful Wood-Hawk orchis spectabilis). (Dryotri- Rose-breasted Grosbeak (Hedyimeles ludovicianus). Mexican luxuosus). Yellow-bellied Tanager Slaviventris). Blue Jay (Cyanocorax (Calliste Scarlet Cardinal (Cardinalis pheni- ceus). Baltimore Hangnest (Ieterus balti- more). 3 Blue Tanagers (Tanagra episcopus). Green - tailed Towhee (Oreospiza chlorura). Allied Saltator (Saltator senilis) Thick-billed Violet ‘Tanager (Hu- phonia laniirostris). Naked-eyed Pigeon nophthalma). 2 Yellow-winged Sugar-birds (Caveba cyanea). (Columba gym- Lavender-backed Finch (Spermophila castaneiventris). Black Manucode (Manucodia atra)... Black-throated Hangnest gularis). 3 Blue Birds (Sialia sialis) Brown-eared Bulbul (Hemixusflavala) (Icterus Chilian Starling (Cureus aterrimus). White-throated Jay Thrush lax albogularis). (Garru- Rainbow Bunting (Cyanospiza le- clancheri). Rufous-necked Tanager cayana). Levaillant’s Francolin (Francolinus levaillanti). Golden-eyed Babbler sinense). Scoter (demia nigra) ...... Grey-necked Serin Finch canicollis). (Calliste (Chrysomma (Serinus HABITAT, Guiana. Sumatra. Brazil. W. Africa. India. do. do. do. N. America. do. Africa. W. Africa, N. America. Mexico. S. America. do. N. America. S. America. N. America. Brazil. do. Venezuela. S. America. Guiana, Aru Islands. Mexico. N. America. India. Chili. India. Mexico. S. America. Cape Colony. India. British Isles, S. Africa, 409 TYPE. Short, very thick. Long, thin. Thick. Long, thin. Long, thin. Long. Short, thin. Short, thick. Medium, thick. Short, thick. 2 kinds: one short, and one long with very pointed ends. Long. Short. Medium, straight. Long. Short to medium, thick. Long. Short, thick. Short, straight. Long. Long, thick. Long. Short, thick. Very long. Short. Short, straight, Short. Medium, Long. Short, thick, no vacuole. Long, very pointed, Long, thick. Long, thick. Long. Striated, Long. 410 MR. H. G. PLIMMER ON Birps (continued), Name. Haprrar. Typr. Capueira Partridge (Odontophorus S. America. Long. capueira). Occipital Blue Pie (Uvrocissa occi- India. Short. pitalis). Barred Dove (Geopelia striata) ...... do. Short, very thick. White-backed Piping Crow (Gymno- Australia. Short, thick. rhina leuconota). ReEprriues AND BATRACHIANS. Bearded Lizard (Aimphibolurus bar- Australia. Short, thick. batus). Spiny-tailed Iguana (Cyclura acan- C. America. do. thura). 8 Giant Toads (Bufo marinus)......... 5. America. do. Pine.Snake (Pitwophis sayi)............ N.America. Long. *2 Edible Frogs (Rana esculenta) ...... Kurope. Short. I now come to the Protozoa, and will take first a spirochete, whieh belongs to the so-called Proflagellata. The spirochetes are important as being the cause of such diseases as relapsing fever, tick fever, and syphilis. This particular one was found in the blood of a Monkey—Cer- copithecus sabeus—and is of the type of Spirocheta recurrentis, the cause of relapsing fever. SPIROCH ELA FOUND IN THE BLOOD OF A Namen. HaABirat. CHARACTER, Green Monkey (Cercopithecus sabeus). Sierra Leone. Like Sp. recurrentis. The next in order are the Flagellates, and of these 1 will take first the Trypanosomes, which are flagellated organisms living in the blood serum, ‘hey are the cause of many deadly diseases in man and animals. I have found Trypanosomes in 50 mammals, 7 birds, and 3 amphibia. 49 of the mammals were ordinary rats, out of 500 examined at the Gardens for another purpose, in which the ordinary rat trypanosome, 7/rypanosoma lewist, was found. The other mammal was a Fat Mouse (Steatomys pratensis) from S. Africa, in which trypanosomes have not hitherto been described. 'The bird trypanosomes are all new in these particular birds ; but they would appear to belong to the general type of Trypanosoma avium. These bird trypanosomes are quite different to the mam- malian variety: they are very large and thick, they stain densely and indistinctly, and they move very slowly. The spleens of the infected birds were large and their blood anemic, ‘The trypano- somes found in reptiles were all of the type of Z'rypanosonia rotatoriwm, which was the one described by Gruby in 1843. It has not been described before in the Tree Frog (Hyla venulosa). BLOOD-PARASITES,. Al] 'TRYPANOSOMES FOUND IN THE BLoop or MAMMALS. NéMe. Fat Mouse (Steatomys pratensis) ............ *49 Rats (Epimys norvegicus) CHARACTER. Of Nagana type. T'. lewisi. Hapirar. S. Africa. England. Birps. Red-winged Francolin (Francolinus S. Africa. Lon] gariepensis). T’. avium type. Chukar Partridge (Caccabis chukar) ...... India. do, Marsh Bird (Leistes guianensis) ............ Demerara. do. Waxbill (Hstvelda melpoda) Australia. do. Levaillant’s Francolin (Francolinus levail- Cape Colony. do. lanti). Dial Bird (Copsychus saularis) India. do, Bower Bird (Amblyornis subalaris)......... New Guinea. do. BATRACHIANS. *Edible Frog (Rana esculenta) ........ ...... Europe. T. rotatorium type. *Tree Frog (Hyla arborea)..................... do. do. Tree Frog (Hyla venulosa) S. America. do. There are certain flagellated organisms which may appear in the blood and live there not as actual parasites, but accidentally. In reptiles there are certain kinds of inflammation of the intes- tine, accompanied by ulceration, which cause the walls of the intestine to become permeable, so that some of the flagellated organisms which are often found there are able to get into the blood and live there. The alteration of structure of the intestine during the inanition of hibernation is also favourable to the passage of organisms through the intestinal wall. I have found these flagellates in the blood of 8 reptiles, and they have been either varieties of Heaamitus, found first by Dujardin in 1841 in the frog’s intestine, or of Trichomonas: the former in the frog and tortoises, the latter in the snake. The only other mention of these organisms in the blood is by Danilewsky, in 1889, who found the Hexamitus in the blood of Emys lutaria and Rana esculenta, so that those given in the following list are all new hosts for this kind of infection. In the Hewamitus infections there was general edema of the tissues and ascites, and the organisms were found also in the transudation. INTESTINAL ORGANISMS FOUND IN THE BLoop or REpriLes AND BATRACHIANS, NAME. Haspirat. TYPE oF PaRasiTE. Bull Frog (Rana catesbiana) ............... N. America. Hexamitus. Leopardine Snake (Coluber leopardinus). Europe. Trichomonas. Indian Cobra (Naia tripudians) India. do. Box Tortoises (Cistudo carolina) ......... Three-banded Terrapin (Cyclemys tri- Sasciata). Hog-nosed Snake (Heterodon simus) ...... West-African Python (Python sche)...... Angulated Tortoise (Testudo angulata)... N. America. I. Indies, N. America. W. Africa. S. Africa. Hexamitus. do. Trichomonas. do. Hexvamitus, 412 MR. H, G. PLIMMBER ON [ now come to the intracellular parasites, and will take first the Hemogregarines, which are intracellular parasites occurring chiefly in ‘the reptile group, and, so far as my experience here goes, ‘entirely in that group. I have found them here in 150 reptiles, of 67 different species, and in 41 of these for the first time. The schizont is found generally in the erythrocyte of the host, and is an elongated body with a well-marked nucleus, and with no pigment. Se shizogony occurs generally in the internal organs, especially in. the lungs ; this stage, however, has not yet been observed in all eases, They vary much in their effect on the cell and on the nucleus, and I have indicated in the following table the most obvious of these gregarines very little change takes place in the cell; with others the cell gets smaller and out of shape; with others it gets enormously enlarged and effects. With some hemo- dehemoglobinised. Others again destroy the nucleus, like the Aa@ryolysus of lizards and snakes. Some infections are very severe, scarcely a cell is unaffected, and there may be sometimes as many as four parasites in a cell, T have found a very remarkable one of a new type ina Bengal Monitor. ‘This parasite divides the nucleus of the cell into two parts which remain connected by a thread of nuclear material which has a tiny enlargement at its central point, T have found that the schizogony of this parasite takes place in the lung, several stages of which are shown in the Plates. H.®MOGREGARINES FOUND IN Name. ¥3 Moorish Geckos (Tarentola meau- ritanica). Bengal Monitor (Varanus benga- lensts). %2 Rat-tailed Serpents (Zachesis lanceolatus). + SS i een Bs i 2 Teguexins (Zupinambis tequevin). 3 Black- spotted Lizards (lgi- reides nigropunctatus). *9 Indigo Snakes (Coluber corais)... Vivaceous Snake (Tardophis fallax) ¥3 Lace Monitors (Faranus varius). *Horseshoe Snake (Zamenis hippo- erepis). *6 Indian Pythons (Python molwrus). 20 Diamond Rattlesnakes (Cre- talus atrox). *King Snake (Coronella getula) HABITAT. Mediterranean. India. S. America. do. Adniatic. C. America. . Europe. Australia, S. Europe. India. Texas, N. America. tHE Buoop oF Rerriwes AND BAYTRACHIANS. CHARACTERS. Parasites large and doubled over at one end, sometimes at both. Nucleus of cell divided into two by the parasite, with connecting thread. Schizogony in lungs. Host-cells enlarged. Parasites bulky and very full of granules ; many with only remains of nucleus attached, Short to medium, some bottle-shaped ; chromidia at both ends; free sporonts in all. Host-cells enlarged and dehemoglobi- nised, Medium ; cells unaltered. Parasites large and contain granules ; cells unaltered. Bulky ; turned over at one end. Host-cells often deformed; generally diminished in size. Host-cells enlarged and dehemoglobi- nised, Very thick, short forms; some free sporonts which are long and pointed, Name. *Hoary Snake (Paeudaspia cana) ... Puff Adder ( Bitia arictana) *Mexican Snake (Coluber melano- leuens).° Senegal Chameleon senegalensis). #6 Cobras (Naia tripudiana) Large Grieved Tortoise (Podo- Cnemis ExXpansa). *Alligator (Alligator mississippi- (Chameleon ensis). 2 Clarke’s Lizards (Sceloporus clarkii). *3 Diamond Pythons (Python spilotes). Gallot’s Lizard (Lacerta galloti)... *5 Indian Rat Snakes (Zamenia MUCOBA). * Msculapian Snake (Coluber longis- simus). 42 Common Boas (Boa constrictor). Reeves’s Terrapin (Damonia recvesi) * Reticulated Python (Python reticu- latus.) 4 Chicken Snakes (Coluber obso- letus). 2 Corn Snakes (Coluber quttatus) . Panded - tailed Snake (Leptophis liocercus). 4 Spiny-tailed Snakes (Cyclura acanthura). *3, Coach-whip Snakes (Zamenis flagdliformis). *3 Pond Tortoises (Emys orbhicu- laria). Painted Terrapin (Chrysemys picts). Smaller Rattlesnake (Sistrurus miliarius). Boddaert’s Snake (Drymohius hod- daerti). 3 Black Snakes (Zamenis con- strictor). Hog - nosed Snake (Heterodon simus). Mocassin Snake (Tropidonotus fasciatus). Pine Snake (Pituophis sayi)......... *4 Giant Toads (Bufo marinus) ...... *2 Spanish Terrapins (Clemmys leprosa). Horrid Rattlesnake (Crotalus horridus). 4 Bell's Cinyxes (Cinirys helliana), 8S. America. N. America. do. Australia. Canary Islands, India. Europe. S. America. China. E. Indies. N. America. do. S. America. C. America. N. America. 8. Europe. N. America. do. C. America. N. America. do. do. do. S. America. Spain. N. America. C. Africa. BLOOD-PARASITES. 43 HAeirat. CHARACTERS. §. Africa. Short, bulky, and full of granules; howt- cells deformed. do. Medium ; host-celle unaltered. Mexico. Host-cells very much enlarged. W. Africa. Short, bulky. India. Long parasites; cells unaltered. Bulky and granular, with eccentric nuclens. Parasites small, granular; nucleus often eccentric. Long, with dense nuclei, some hooked ; cella greatly altered. Very long, doubled over. Adherent to nuclens of host-cell ; granules at both ends. Medium sized; cells unaltered. Medium «ized; adherent to nucleus of host-cell. Long and hooked ; some cells enlarged. Short, thick. with eccentric nuclei. Long, doubled over, cells enlarged. Host-cells enlarged. do. Medium ; cells unaltered. large and granular, cell nearly filled; nucleus compressed and dense. Host-cells deformed; parasite long and hooked at one end, later donbled over. Short and thick, with eccentric nuclei; a few very thin and doubled over. Short and thick, with granules: cell« deformed. Long and thick, with eccentric nuclei. Bulky and hooked; cells deformed. Large and hooked; cells deformed. Long; cells enlarged and ultimately dehamoglobinised. Thin and long forms; cells unaltered. Host-cells enlarged and deh#moglobi- nised. Short and thick; cells unaltered. Bulky ; cells deformed, Long and thin; cells unaltered. Short, thick. 414 Name. Black Sternothere (Sternotherus niger). Hasselquist’s Gecko (Ptyodactylus lobatus). 2 Speckled Terrapins (Clemmys guttata). Green Tree Viper (Atheris chlor- echis). Three-keeled Terrapin (Stawo- typus triporcatus). Egyptian Gecko (Tarentola annu- laris). Hilaire’s Terrapin hilarii). *4 Kyed Lizards (Lacerta ocellata). (Hydraspis *Nilotic Monitor (Varanus niloticus). *2 Cook’s Tree Boas (Corallus cooki). Green Tree Snake (Dendraspis viridis). *2 Russell's Vipers (Vipera russelli). *2 Hryxs (Hryx johnt)................0 3 Dahl’s Snakes (Zamenis dahli)... *Confluent Rattlesnake (Crotalus confluentus). Glass Snake (Ophiosaurus apus) ... Long-nosed Viper (Vipera ammo- dytes). Tuberculated Iguana (Iguana tuberculata). Peloponnesian Lizard (Lacerta peloponnesiaca). Madagascar Boa (Boa madagas- cariensis). West African Python (Python sebe). 2 Dark Green Snakes (Zamenis gemonensis). Square-marked Toad (Bufo regu- lanis). HABITAT. W. Africa. Egypt. N. America. W. Africa. C. America. Egypt. Brazil. 8. Europe. Africa. W. Indies. W. Africa. India. do. S. Europe. N. America. S. Europe. do. C. America. S. Europe. Madagascar. Tropieal Africa. Europe. Africa. MR. H. G. PLIMMER ON CHARACTERS. Medium sized. Short; cells deformed. Short; bulky; nucleus eccentric. Long and thin. Medium. Short, bulky; cells deformed. Long, doubled over. Host-cells enlarged and some dehemo- globinised. Long, thin; some bottle- shaped. Medium, thick. Host-cells deformed, short; nucleus not central. Large, often two in cell which is not enlarged. Bulky : cells deformed. Long, with hooked end. Long, thin; turned over at both ends. Long, doubled over. Large and granular; host-cells elongated. Bulky ; cells not enlarged. Short, stout, sometimes round. Short. Short, thick ; cells deformed. Schizo- gony found in liver. Medium sized. Cells enlarged and dehwmoglobinised ; parasites long and thin. Short and very thick. The next group is that of the Plasmodide, to which the various malarias belong. I have found only one mammal—a Green Monkey—infected with, malaria, probably Plasmodium kocha. It is uncertain, because I could only get certain stages; the host-cells do not seem to be greatly altered. In the birds there are two kinds of intra-corpuscular parasites, the Plasmodium precow and Hemoproteus danilewskyi, which have been sometimes confused, but are really entirely distinct. The Plasmodium precow has many points of similarity to the parasites of human malaria, and in many stages is so like that it can only be differentiated by the presence of the oval nucleus of BLOOD- PARASITES. 415 the bird’s erythrocyte. I have found Plasmodium precor in 20 different species of birds, in none of which has it been recorded before. Geographically the distribution of the 21 birds in which I have found this parasite is as follows :—KEurope 1, Asia 4, Africa 5, Americas 8, Australia 3. It is a deadly disease in birds, and produces a marked anemia, and considerable enlarge- ment of the spleen and changes in the bone-marrow. [ have found Plasmodia in 6 reptiles of 5 different species, in all for the first time. They all probably fall under the heading of Hemocystidium. They all have pigment, and when large have rather the appearance of Hamoproteus. altered. PLASMODIAL PARASITES FOUND IN THE The cells are not Bicop or MammMats.— Plasmodiwm kochi. NAME. *Green Monkey (Cercopithecus sabeus) .................. Hapirar. Sierra Leone. Birps.— Plasmodium precoc. Long-tailed Glossy Starling (Lamprotornis eneus) . Japanese Hawfinch (Coccothraustes melanura) 2 Crowned Cranes (Balearica regulorum) Orange-cheeked Waxbill (Estvrelda melpoda) ......... Small Hill Mynah (Gracula religiosa).................. Red-and-Blue Macaw (Ava macao) ee Reese VEN Tambourine Pigeon (Tympanistria bicolor) 2.22.2... Red-eared Bulbul (Pyenonotus jocosus) ba dib ess Nutcracker (Nucifraga caryocatactes)................. Yellow-breasted Tanager (Calliste thoracica) ......... Blue Sugar-Bird (Daenis cayana) .......000.............. Brazilian Hangnest (Icterus jamaicdi).................. Ox-Bird (Tenor alector) ... cerervees pep ell): Flycatcher (Stoparola melanops) ........................ Jay-Thrush (Garrulax leucolophus) .......000...5. 0005. Mexican Finch (Carpodacus mexicanus) ............. Rainbow Bunting (Cyanospiza leclancheri) Blue-tailed Fruit Pigeon (Carpophaga concinna) Cuban Finch (Phonipara canora) ..... Scaly Dove (Scardafella squamosa) ..... W. Africa. Japan. S. Africa. W. Africa. India. C. America. W. Africa. India. Europe. Brazil. S. America. Brazil. W. Africa. Australia. N. India. Mexico. Mexico. Aru Islands. Cuba. S. America. Reptites.—Hemocystidium. Bell’s Cinixys (Cynivis helliana) wae Three-tailed Terrapin (Staurotypus triporcatus) Painted Terrapin (Chrysemys picta) Home's Cinixys (Cinixys homeana) .................... 2 Eroded Cinixys (Ciniwys erosa) ................... Africa. B. Honduras. N. America. W. Africa. W. Africa. The second parasite of birds is Hamoproteus danilewskyi, which has been found in a large number of cases : is unknown. and its development Tt is found first as a small irregular body in the 416 MR. H, G. PLIMMER ON erythrocyte of the bird and then grows in the long axis of the cell, and turns round the end of the nucleus, and it contains pigment. It has been shown by the Sergents and by Aragao that a species of fly—Lynchia maura—is the principal host. The process of fertilization in these parasites has been described by MacCallum, and it is believed that other stages are found in the lungs. I have found these parasites in 69 birds of 48 different species, in 46 of the latter for the first time. The following list shows that the parasite is very widely distributed. 76 of the hosts came from Africa and 42 from the Americas. H_&MOPROTEUS DANILEWSKYI FOUND IN Brrpbs. Name. Hapirar. 3 Blue-winged Tanagers (Calliste cyanoptera) ...... S. America. Bouvier’s Owl (Scotopelia bouviert) ...... 2.0... Lagos. 3 Great-billed Touracous (Turacus macrorhynchus) W. Africa, Black-shouldered Tanager (Calliste melanonota) ... Brazil. Porphyrio (Porphyrio madagascariensis) ............ Madagascar. 2 Green-headed Tanagers (Calliste tricolor) ......... S. America. Red-sided Kelectus (Heleetus pectoralis) ............ New Guinea. White-backed Piping Crow (Gymnorhina lewconota) Australia. Hanging Parrakeet (Loriculus galgulus) 0.0.0.0... Malacca. 3 Brown-necked Parrots CS Oa ge ce W. Africa. Bower Bird (Amblyornis subalaris) ....... .... New Guinea. 5 Yellow-winged Sugar-birds (Cereba nea cee S. America. 5 Maequeen’s Bustards (Houbara macqueeni) ...... W. Asia. 3 King Birds of Paradise (Cicinnurus regius) ...... New Guinea. Dial Bird (Copsychus saularis) ..c....cc.cc cece ecee ees India. *African Barn Owl (Strix flammea) .........0000.... S. Africa. Grenadier Weaver Bird (Huplectes oryx) ............ W. Africa. Parrot Finch (Mrythrura psittacea) ......... 060.6... New Caledonia. Australian Sheldrake (Tadorna tadornoides) ...... Australia. 2 White-crested Touracous (Luracus corythaix) ... S. Africa. Mexican Hangnest (Cassiculus melanicterus) ..... Mexico. Palm Tanager (Tanagra Bear) Sedona RAGE RE ny OSHA CTUCAs Honey-eater (Péilotis fusca) ......ccn6cskeeecuseeseee Australia. Schlegel’s Dove (Calopelia puella) .........cccc cece W. Africa. Cut-throat Finch (Amadina fasciata) ......cc W. Africa. Scops Owl (Scops leucotis) .........se.eseeseeeeeeeeeeeee Gambia. Black-throated Lorrikeet (Trichoglossus nigrigu- New Guinea. laris). Grass Finch (Erythrura prasinad) v......ccec00.... Sumatra. Baer’s Duck (Fuligula baert) .............sceceeeeess India. 2 Kestrels (Tinnunculus alaudarius) ....... British Isles. Spotted-backed Weaver (Hyphantornis “ga TeaceTo) Africa. Festive Tanager (Calliste festiva) ..........c0000. Brazil. Rose-breasted Grosbeak (Hedymeles ludovicianus). N. America. Senegal Touracou (Twracws persa) .......0000. ~~ W. Africa. *Cape Hagle-Owl (Bubo capensis) .......c00.c eee Ss Africa. Hooded Siskin (Chrysomitiris cue TEARS veces IN. America, Fuscous Honey-eater (Ptilotis fusca) .........0.0.... Australia, BLOOD-PARASITES. 417 Name. Hapirar. Whydah Bird (Vidua paradisea) ..................... W. Africa, Manchurian Crane (Grus japonensis) ................... N. China. Lawes’ Bird of Paradise (Parotia lawesi) ............ New Guinea, Eagle-Owl (Bubo maculosa) .............................. S, Africa, Indian Roller (Coracias indica) ....................... Yndia. Yellow-cheeked Tit (Machlolophus wanthogenys) ... do. 2 Blue Tanagers (Tanagra episcopus) ............... 8S. America, Fraser’s Eagle-Owl (Bubo poensis) ...................... W. Africa. Cape Sparrow (Passer arcuatus) ..... ................... ®. Africa. 2 Purple-capped Lories (Lovins damicella) ......... Moluceas. Purple Sugar-Bird (Careba cyanea) ................... S. America. One other parasite remains to be mentioned—the Leuco- cytozoon: this is found in the blood of birds in the form of a long, spindle-shaped, unpigmented body, about three or four times the length of a normal erythrocyte, and about one third of the breadth. Unstained they are colourless and are always free from pigment. They are rare, and at present uncertain as to position, and they occur only in the blood in the sexual forms. The dull plasma staining may indicate that the forms in the blood are macrogametes, The earlier observers of this parasite— Danilewsky and Ziemann—believed that the host-cell was a leucocyte, but Laveran has shown that it is an erythrocyte. There would seem to be some analogy between the curious enlargement of the host-cell and the enlargement and dehzemo- globinisation of the erythrocytes of snakes, containing one of the varieties of hamogregarines mentioned before. I have found these parasites in two birds only, both of which are new as hosts, LEUcoCcYTOZzOA FOUND iN PHE BLOOD oF Birpa. NAME. Haprrat, Scaup’s Duck (Fuligula mavila) ............-0000....... Europe. Levaillant’s Francolin (Fyancolinus levaillanti) ... Cape Colony, EXPLANATION OF THE PLATES. The microphotographs were made for me hy Dr. A. Norman, and the drawings were made to scale by Mr. W, S. Berridge. The scale divisions are ‘01 millimetre. Pu, XLIX, Fig. 1. Pilavia in the blood of a Wallaby. x 250. The eapsyle can be seen with a lens gs a white line outside the filaria. The blood in this case was very disorganised and there was a marked -eycocytosis, In the ponch there was a very young foetus in the body- cavity of which there was one adult filaria similar to others found in the body-cayity of the mother, No embryo tilariz were found in the blood ot the foetus. Fig. 2, Filavie in the blood of a Giant Toad. > 300. The capsule is quite visible, and also the pointed anterior end. These were present in large numbers. Proc. Zoot. Soc.—1912, No. XX VII. 27 Hic, 3 Fig. 4, Fig. 5 Fig. 6 Vie. 7 Fie, 8 Fig. 9 Fig. 10. Iie, Il. Fig. 12 Fig. 13. Fig. 14. Fig. 15 Fig. 16 Fig. 17 Fig. 18. Fig. 19. ON BLOOD-PARASITES. . Spivochetes in the blood of a Green Monkey. X 1000. The monkey had also malaria (not shown). . Trypanosomes in the blood of a Dial Bird. They are large and thick: the one marked a is probably degenerating, and that marked 6 is of a different shape and stained more easily. . Intestinal organism of Trichomonas type in the blood of a Leopardine Snake. 1000. . Intestinal organisms of Hexamitus type in the blood of a Bull Frog, Pits 1, . Filariez in the blood of a Pinche Marmoset. X 135. Present in very large numbers. The capsule is not distinguishable. . Hemogregarines in the blood of a Hog-nosed Snake. X 500. A very severe infection, nearly every erythrocyte contaimed one or more parasites. At a parasites which have escaped from the erythrocytes and are free in the blood are seen, and at 6 a cell containing so-called male and female forms. Veit, Mil. . A drawing of various forms of the same Hewxamitus type of organism of which a photograph is shown on Pl. XLIX. fig. 6. A scale-drawing of the Hemogregarine found in the blood of a Hog-nosed Snake, of which a photograph is given on PI. L. fig. 8. a. An erythrocyte containing two parasites of so-called male and female types. 6. Two parasites free in the blood, one hyaline, the other very granular. ¢. Schizogony; two cysts from the lung. d. Also from the lung; probably an earlier stage than ec. A scale-drawing of Heemogregarines in the blood of a Black Snake. At a are two parasites joined together by the remains of the nucleus of the erythrocyte. 6 points to a number of probable odkinete forms found in the stomach of a tick found upon the snake. . Hemogregarines in the blood of a Rat-tailed Serpent. > 500. This isa late stage of the infection, showing the parasites attached to the remains of the nuclei of the erythrocytes. Hemogregarines in the blood of a Mexican Snake. X 300. Ata can be seen infected erythrocytes which are enormously enlarged, very much thinned, and entirely dehamoglobinised. Pru. LID. Drawing of Hzemogregarines from the blood of a Black-spotted Lizard. Showing enlargement of the corpuscles and the various forms assumed by this parasite. At @ is an erythrocyte very much enlarged and altered in shape and texture, and vacuolated. At 6 are two free forms, showing considerable nuclear activity and very granular protoplasm. . An erythroevte from the bone-marrow of the same Black Snake to which Fie. 11 refers. X 750. It contains two hemogregarines of the so-called male and female type. . Drawing of Hemogregarines from the blood of a Madagascar Boa. En- larged cells containing one and two parasites. At @ is a cyst from the lung, showing commencing schizogony. . Drawing of a leucocytozoon from the blood of a Scaup’s Duck. At a are deformed erythrocytes containing the parasite; at 6 remains of nuclei of erythrocytes; at c a macrogamete; and at d probably a microgamete. Pr. LIII. Blood of a Brazilian Hangnest, showing infection with Plasmodium precox. X 450. Many of the infected cells show a multiple infection as at a. Blood of a Crowned Crane showing the same parasite as Fig. 18. The blood is very anemic. There are single and multiple infections of the erythrocytes, and at a is a parasite breaking up into a rosette. PZ Ss ole el Eis : A.S.C. AR.Broom del. Huth,Lith? London. THE AUDITORY REGION IN DIGYNODON. ON THE AUDITORY REGION IN DICYNODON. 419 Pr LDV. Fig. 20. Blood ofa Palm Tanager showing infection with Hemoproteus danilewskyi. Three full-sized parasites are present, and some eariy forms are seen in the photograph as dots in the erythrocytes. Fig. 21. Blood of a Bengal Monitor showing an ordinary hemogregarine and the one mentioned on p. 412 of text. 450. This is probably a double infection as no intermediate stages between these parasites can be seen. At a the ordinary form of hemogvegarine is seen; those erythrocytes marked 6 contain the new type of parasite, to which reference has been made in the text. This parasite stains badly, there is a very small amount of nuclear material in it when stained by any modification of the Romanowsky method or by iron-logwood, and the altered nucleus of the erythrocyte stains very densely. Fig, 22. Drawings of the same parasites. At a the ordinary hemogregarines are shown, and at 6 the other parasite, in an early stage in the drawing to the left, and in the later stage, with the cell-nucleus divided, to the right. 12 ay, LV. Fig. 23. Drawings of the new parasite. The erythrocyte in the photograph and drawings is seen to he deformed, and eventually dehemoglobinised (as in the cell marked a). At 6 is seen the tiny nodule which is generally to be found ou the delicate con- necting-thread between the pieces of the cell-nucleus. The cell marked ¢ contains what appears to be an abortive attempt to divide the cell- nucleus equally: very few of these were found. Fig. 24. Drawings of forms found in the lungs, showing various stages in schizogony. None of these smal! forms have been found in the erythrocytes. No stages were found in the other organs. 23. On the Structure of the Internal Har and_ the Relations of the Basicranial Nerves in Dieynodon, and on the Homology of the Mammalian Auditory Ossicles. sy R. Broom, M.D., D.Se., C.M.Z.S. {Received January 12, 1912: Read Mareh 5, 1912.] (Plate LVI.* and Text-figure 53.) Few questions connected with vertebrate morphology have given rise to a larger amount of discussion than the homology of the mammalian auditory ossicles and the connected problem of the fate of the quadrate in mammals, Most embryologists have been struck with the resemblance of the malleus and inecus to an articular and quadrate ; many comparative anatomists have been impressed rather with the resemblance of the mammalian auditory chain with the auditory apparatus of the Reptilia; while paleontologists, for the most part, have hesitated to believe that the incus could be the quadrate, from the difficulty of imagining the intermediate stages, and have inclined rather to believe that the quadrate has become part of the zygomatic arch, or the meniscus, or become lost, or converted into the tympanic bone. Until a few months ago I was of opinion that the quadrate became either the meniscus or, in those few forms where a meniscus is absent, was lost. It is unnecessary to repeat the arguments * Por explanation of the Plate see p. 425, 27% 420) DR. R. BROOM ON THE by which I have endeavoured to maintain this position; suttice it to say that I now regard the position as untenable, since the element in the Anomodonts which I have long regarded as the tympanic now proves to be unquestionably the stapes. In the type skull of Dicynodon latifrons there is a slender rod- like bone lying in the cavity which is bounded above by the exoccipital, and usually by a dumbbell-like bone below. The stout dumbbell-like bone which stretches from the basioccipital process to the quadrate I have hitherto believed to be the tympanic, and the slender rod-like bone the stapes. New evidence now shows that whatever the slender bone may be— perhaps a displaced part of the hyoid—the supposed tympanic is undoubtedly the stapes, and what I believed to be the fenestra ovalis is the foramen for the vuth nerve. Having the imperfect occiput of a moderate sized Dicynodon, in which the matrix was much hardened by epidote and the bone mainly calcareous, I saw it might be possible to dissolve the bone and leaye a cast of the internal ear and the basicranial nerve-passages. Though on one side much of the internal ear was found to be occupied by calcite, the result of the decalcification on the whole was so satisfactory that the structure of the ear in Dicynodon is now almost as well known as in recent animals, and as much is known of the cranial nerves as is ever likely to be known. The internal ear (Pl. LVI. figs. 1-3) is unlike that of any animal hitherto described, so far as I am aware. While the semicircular canals are apparently not unlike those of recent reptiles or mammals, the vestibule is very remarkably elongated and there is no trace of a cochlea. The vestibule has an upper, somewhat triangular portion, which lies between the upper end of the canal for the viith nerve and the upper end of that for the ixth, xth, and xith nerves. In close contact with the brain cavity there is an upward extension, with which is united the canal common to the anterior and posterior semicircular canals. On the anterior and posterior sides are irregular excrescences, which are perhaps vascular spaces filled with matrix. The broadest part of the vestibule is where the ampulle of the anterior and posterior semicircular canals are situated. From this point the vestibule passes down- wards for a distance about twice as great as the maximum width. To near the middle of this descending portion there is a steady narrowing, but beyond the middle the vestibule again expands and the fenestra ovalis is about as wide as the widest part of the vesti- bule. The fenestra ovalis lies near the middle of the descending basioccipital process, but looks outwards and slightly downwards. This large descending process, so conspicuous in the Anomodont skull, is formed posteriorly by the basioccipital bone, and in front it is supported by the basisphenoid, but there seems considerable reason for believing that the centre portion is partly prootic and partly opisthotie. Down the descending part of the vestibule there appears to be evidence of the suture between the two otic bones. AUDITORY REGION IN DICYNODON, 491 The semicircular canals are lost from the left side of the specimen, and though they are preserved on the right side, as they are partly filled with calcite and the bone is much « epidotised, it 1s impossible satisfactorily to decalcify the right side. Still, sufficient has been successfully accomplished to show at least a part of each anal. The posterior semicircular canal has a distinct ampulla, which hes very close to the canal for the ixth, xth, and xith nerves. From here it passes upwards and forws ards, then inwards, and lastly downwards, doubtless uniting with the upper end of the anterior canal. The horizontal canal, though well shown in its middle region, has neither its anterior nor posterior ends displayed. The position of the canal will be better understood from the figure than from description. The anterior semicircular canal is badly displayed. It runs mainly upwards to unite with the descending part of the posterior canal. The cast of the posterior portion of the cranial cavity and of the basicranial nerves is beautifully preserved. Behind the lower end of the posterior semicircular canal is seen the cast of the large canal for the ixth, xth, and xith nerves; where it leaves the cranial avity if is shghtly extended antero- posteriorly, but where it leaves the skull it is flattened a little vertically. The canal for the xiith nerve passes down a short distance behind the jugular foramen, and unites with it before it leaves the skull. The fact that the xiith nerve has only a single canal is interesting in view of the fact that in the Cotylosauria, as exemplified by Pareiasaurus, we have two foramina for the xiith nerve, and a similar condition is found in the Cynodontia and in the Marsupialia. In the Pelycosauria, as has been shown by Case, and in the Eutheria, there is, as in the Anomodontia, only a single foramen for the xiith nerve. The canal for the viith nerve lies a little in front of the vestibule. It is long and narrow and passes downwards and slightly outwards, and ends in the small foramen seen at the bottom of the deep groove between the back part of the basi- sphenoid and the pterygoid. ; In front of the specimen is seen the deep pituitary fossa, and below it the carotid canal. The latter begins at a small rounded foramen near the front of the posterior processes of the basi- sphenoid. The main part of the canal passes upwards, forwards, and slightly inwards, and unites with the canal of the opposite side just in front of the hypophysis. From the lower end of the canal is given off a smaller canal, which passes upwards and somewhat more forwards. While the large canal is pretty certainly that for the carotid artery, the smaller is possibly for the arteria ophthalmica. Whatever be the condition of the arteries within the cranial cavity, it must have been very unlike that of Sphenodon oy other living reptiles, and though perhaps a 422 DR. R. BROOM ON THE little more like the condition in mammals, the resemblance could not have been very close. The stapes has long been an element which gave rise to difficulties. So far as | am aware, the first author who gave a good figure of the bone was P. Fischer, in 1870, and he regarded the element asthe pterygoid. From nearly all the British Museum skulls it has been removed during development, but it still remains and is well shown in the skull which forms the type of Aiste- cephalus chelydroides. Unfortunately, unlike most of Griesbach’s work, his figure of this skull in Owen’s Catalogue is rather poor, and in the description Owen says nothing about the bone in question. But in any case, as Owen mistakes a portion of the squamosal for the quadrate (his “tympanic”), though the quadrate itself is present in a fairly well-preserved condition, it is manifest that he had not a very clear idea of the structure of this part of the skull. Seeley, when studying the Anomodont skull in 1888, took the massive stapes to be a malleus, and the unquestion- ably homologous bone in the Cynodonts he later described as possibly a ‘straight cochlea.” Hitherto, I have always looked upon it as the tympanic. Now we know that it is certainly the stapes, though so very unlike the stapes of any living form. Though a considerable number of Anomodonts are known showing the stapes in position and in perfect condition, I shall describe and figure it and the related bones from the beautiful specimen which I have recently made the type of Oudenodon kolber (Pl. LVI. figs. 4-6). The stapes is here a short dumbbell- shaped bone with the ends flattened and shghtly oblique. Across one diagonal it measures 30 mm., across the other 23 mm. © The narrowest part of the middie measures 12 mm. across. When viewed from behind the stapes is seen to be much flattened, the narrowest part of the bone measuring only 4 mm. in thickness, A considerable part of the inner end has probably been carti- laginous. The outer end is much flattened and is closely articu- lated to the inner side of the quadrate. There seems to be no supra- or éxtra-columella, or if there has been one it must have been relatively very small. The quadrate, one would readily think, would be the most easy bone in the skull to identify. Many years ago Owen figured what he believed to be the quadrate, and nearly everyone has agreed with his determination. There is a large articulation, about as broad as long. Along its inner third there runs an antero- posterior ridge; near the middle there is an antero-posterior shallow groove ; and the outer part of the articulation is a convex disc. This outer part forms the base of a bone which on passing upwards becomes a wide fan-like squamous plate, which is closely applied to the squamosal. If the whole articulation be quadrate this squamous plate must also be quadrate, as has been the view of Owen, Seeley, and myself. It would now appear that about half of the articulation is formed by the quadrato-jugal, and that the squamous plate is also thus quadrato-jugal. The squamosal comes down behind the quadrate and quadrato- AUDITORY REGION IN DICYNODON. 423 jugal almost to the articulation. A shallow but distinct groove can be traced down, partly formed by the squamosal and partly by the exoccipital. This is evidently for the external auditory canal, but how the tympanic membrane was attached or whether there was one at all, the evidence does not show. Not improbably there was a membrane attached to the exoccipital, squamosal, and to a small part of the quadrate. Though the articular region is more perfectly known in the Anomodonts than in other Therapsida, a good deal is known about its condition in the other groups. In the Pelycosaurs the stapes is large and of a peculiar shape, the quadrate is aiso large and forms the whole of the articulation, and a small quadrato-jugal is present. Little is known of the condition in the Dromasauria. In the Dinocephalia the quadrate is large and forms the whole articulation, and a quadrato-jugal is apparently always present. It is known in Delphinognathus, Moschops, and Tapinocephalus. The stapes is probably very similar to that in the Anomodontia. In the Therocephalia the quadrate is small, but forms the whole articulation. No quadrato-jugal is known in any genus. The stapes is not well known, but appears to be large andlong. Inthe Cynodonts a quadrato-jugal is never present and the quadrate is usually small. In some genera (e. g. Cynognathus) a considerable part of the articular surface for the lower jaw is formed by the Squamosal, the quadrate forming only about three-fourths of the joint. The stapesin Bawria and Cynognathus is a fairly strong cy- lindrical rod : in 7'rirachodon it is also a long rod, but very slender. Inal] these genera its outer end is firmly attached to the quadrate. As there are very strong reasons for believing that the mammals are descended from one of the mammal-like reptiles, probably a primitive Cynodont, all the information that can be obtained on the structure of the auditory apparatus is especially welcome, because of the light it may throw on the nature of the mammalian auditory ossicles. And the certain determination of the stapes seems to settle the homologies of the various elements. Had the outer end of the stapes been free and given attachment to a carti- Jaginous extrastapedial, the dispute might have gone on. But there is apparently no extrastapedial, and certainly the greater part of the outer end of the stapes is firmly fixed to the quadrate. The similar attachment of the stapes to the incus in mammals is striking; and though I have long advocated another view, I now feel forced to agree to the view that the incus is the reptilian quadrate, as advocated so many years ago by Reichert. The shipping out of the quadrate from the joint is not now a very serious difficulty, for in Cynognathus we see it already partly slipped out. Nor is there any very great difficulty in under- standing how the new dentary-squamosal joint arose. In Cyno- gnathus, the posterior end of the dentary nearly takes part in the joint, and there is no difficulty in realising the next stage in the evolution, where the dentary and articular together hinged on the squamosal and the quadrate. As the direct articulation of the dentary on the squamosal became more firmly established, the 2A DR. R. BROOM ON THE A. Diagrammiatic representation of artictilation in Dicynodon. B. Articulation in the Cynodont, Cynognathus. C. Hypothetical diagram of the condition when the dentary articulates with the squamosal. D. Hypothetical diagram of the condition wher the articular and angular no longer support the jaw. E. Hypothetical diagram of the condition when the articular and angular take on their auditory function. F. Diagram representing the perfecting of the auditory function (the mammalian condition). AUDITORY REGION IN DICYNODON. 495 quadrate, articular, and angular degenerated, and might have been lost had not the attachment of the stapes to the quadrate compelled them to take on an auditory function. The. tracing of the steps by which the articular became the malleus and how the manubrium was formed is a matter of some difficulty in our ignorance of the position of the tympanic membrane, but we may assume as very probable that soon after the dentary-squamosal joint was formed, the angular and articular rapidly degenerated and ceased to move with the jaw. The tympanic membrane, which possibly in the Cynodonts lay behind the plane of the articulation, probably in the early mammals became shifted more forwards and inwards, and the articular came to support the membrane by the development of the manubrium, while the angular also took part in the support of the membrane and became the tympanic bone. Gaupp is probably correct in regarding the goniale as not the homologue of the angular, but a distinct membrane-bone closely associated with the articular. In the series of six diagrams given (text-fig. 53, A-F), the probable course of the evolution of the auditory ossicles is shown trom the Cynodont type to the type found in the mammal. Though the first figure (A) represents the Anomodont type, this must not be looked upon as on the direct mammalian line, but as a specialised modification of the ancestral type. In fig. B we have represented the Cynodont type as seen in Cynognathus. The articulation is formed by the articular hinging on the quadrate and squamosal, The dentary alinost reaches the joint. Fig. C represents the probable condition in the later Cynodont type when the dentary came to take part in the articulation. Fig. D represents the later stage when the quadrate has completely slipped out from the joint and the articular and angular have degenerated and no longer move with the dentary. In fig. E we have represented what was the probable condition when the articular and angular first became specialised for their auditory function. This is almost the Monotreme condition. Fig. F represents the condition in the typical higher mammal. EXPLANATION OF PLATE LVI. A.S.C. Ascending semicircular canal; B.O. Basioccipital; B.S. Basisphenoid ; Car. Carotid artery; H.O. Exoccipital; E.P¢. Epipterygoid?; ¥.O. Fenestra ovalis; F.M. Foramen magnum; H.S.C. Horizontal semicircular canal; Ju. Jugal; O.C. Occipital condyle; P.S.C. Posterior semicircular canal; Pé. Ptery- goid; Q.J. Quadrato-jugal; Qu. Quadrate; Sq. Squamosal; S¢. Stapes; 7y.M. Tympanic membrane; Vesé. Vestibule. Fig. 1. Left side of decalcified brain region of small Dicynodont. Nat. size. . Right side of partly decalcified brain-region of small Dicynodont. Nat. size. bo 3. Cast of osseous labyrinth of small Dicynodont, restored from the facts revealed by the two sides. Nat. size. 4. Quadrate region of Oudenodon kolbei. Reduced about one half. Front view. . Quadrate region of Oudenodon kolbei. Reduced about one half. Lower view. 6. Quadrate region of Oudenodon kolbei, Reduced about one half. Back view. Or 496 PROF. G. O. SARS ON 24. Zoological Results of the Third Tanganyika Expedition, conducted by Dr. W. A. Cunnington, 1904-1905. Report on some,larval and young stages of Prawns from Lake Tanganyika. By Prof. G. O. Sars, C.M.Z.S. [| Received December 5, 1911: Read March 5, 1912.} (Plates LVII.-LX.*) INTRODUCTION. In the tow-nettings taken by Dr. Cunnington during the Third Tanganyika Expedition and placed in my hands for examination of the Copepoda and Ostracoda, some larval and young stages of Prawns were also found. Having submitted these stages to a closer examination, I find that some notes about them may be of interest. We owe to Prof. E. von Daday a rather elaborate account of the postembryonal development of Caridina iilotica, var. gracilipes (=C. wyckii de Man) from Lake Victoria Nyanaza, and I have also myself had occasion to examine some larvee from that lake, occurring in the samples taken by Dr. Cunnington. They agreed on the whole very well with the descriptions and figures given by Prof. Daday. On the other hand, the larvee found in the samples from Lake Tanganyika have proved to be rather different, apparently owing to the fact that they belong to genera quite different from Caridina. In the present paper I propose to describe three larval forms and one young one, representing as many different stages of development. Two of these forms undoubtedly fepresentl very early larval stages (so- called Zoée); but they differ conspicuously both in size ad in the development of the appendages, and apparently belong to two quite different kinds of prawns. Of course it is very difficult to decide with any claim of. certamty as to the species or even genera to which these larve are referable ; but I believe that they are in themselves interesting enough to merit a detailed csserpnen: They are here simply recorded as Zoéa Nos. 1 and 2, though some suggestions about their probable origin will be sth forth. The 3rd form isa larva in the last, so- called Mysis stage; and the 4th is a very young prawn in the Ist postlarval stage. Both these forms admit of being more certainly referred to a definite species. At the close of this paper some general remarks will be given. Zoiia No.1. (Pl. LVIL) This larva undoubtedly represents the very first postembryonal stage of some Tanganyika Prawn, having apparently just been hatched. It is remarkable for its small size and the very simple structure of the appendages, being indeed the most primitive * For explanation of the Plates see pp. 489-440. Peano. IOIACPE UVil, London Stereoscopic Co. imp G.0. Sars. PRAWNS FROM LAKE TANGANYIKA. Pees Vola. Play: London Stereoscopic Ce. imp. G.0.Sars. PRAWNS FROM LAKE TANGANYIKA. «ave i ger lole. re Lia. G.0. Sars. PRAWNS FROM LAKE TANGANYIKA, FZ. VOLE An ae G.0. Sars. London Stereoscopic Co. imp. PRAWNS FROM LAKE TANGANYIKA. PRAWNS FROM LAKE TANGANYIKA, 427 Oaridean larva that [ have ever met with, and in so far is very different from the earliest stage of Caridina wilotica described by Prof. Daday under the name of Muzoéa. The length of the specimen examined, measured from the anterior edge of the eyes to the end of the caudal plate, is only 70 mm., and the present larva is accordingly not even half as large as the earliest stage of Caridina wilotica, the length of which, according to Prof. Daday, is 1‘70 mm. If we imagine the larva curled up in its original embryonic attitude, we may approximately determine the length of the ovum from which it has escaped to have been 0°25 mim. by a width of O15 mm, This agrees pretty well with the measurements of the ova in Limmno- caridina spinipes given by Dr. Calman, and as the form of the antennal scale in the present larva agrees better with that in this species than with that in any other of the Tanganyika prawns, I am led to the suggestion that it perhaps might be referable to L. spinipes, of which indeed an adult specimen was found in one of the four samples in which the present larvee occurred, The general form of the body (Pl. LVII. figs. 1 & 2) is moderately slender, with the anterior division somewhat tumid and rounded oval in shape. The carapace is evenly convex above and slightly emarginate behind in the middle, leaving the dorsal part of the hindmost segment of the trunk uncovered. At the antero-lateral corners a well-defined spine is present pointing obliquely outwards (see fig. 1). The anterior part of the carapace is badly defined, and no true rostrum could be detected, though a narrow stripe is seen exténding forwards in the middle, without, however, forming any projection in front of the eyes. The latter ave rather im- perfectly developed, as compared with these organs in most other Caridean larve, They are apparently quite immobile, being contiguous at the base inside, and do not project beyond the lateral faces of the carapace. The corneal part is only faintly defined and contains a comparatively small and irregular mass of pigment, from which the visual elements radiate in the form of slight stripes, no corneal facets being as yet visible. Immediately beneath the front parts of the eyes a semilunar lobe occurs (fig. 3, oc.), and within this lobe the simple eye (ocellus) may be faintly traced, for which reason it is here termed the ocellar lobe. Of appendages only the two pairs of antennse and the oral parts are as yet present, and all these appendages exhibit a very simple structure, being filled up with indifferent cells. Especially are the mandibles and maxille remarkable for their imperfect development, and indeed these parts seem to be quite unfit for any true mastication, the larva in all probability subsisting in this stage exclusively on the nutritive yolk, of which a con- siderable quantity is seen accumulated within the anterior part of the body. The relative position of the appendages is best seen on viewing 428 PROF. G. O. SARS ON the animal from the ventral face (fig. 3). The two pairs of antenne (a & a7) originate on each side of a median slightly convex area, the hypostome (H), the one pair, the antennule (a’), occurring in front and inside the other pair, the antenn (a). From the hind part of the hypostome the flap-shaped anterior lip (L) is seen to arise covering the inner parts of the mandibles. The latter (M) are easily observed as two comparatively large, transverse, bow-shaped eminences, and immediately behind them in the middle the two rounded lobules of the posterior lip (/) are clearly seen. Behind these parts the two pairs of maxille have their place, the 1st pair, or anterior maxille (m'), lying inside and slightly in front of the 2nd (m*), which are extended obliquely outwards. The maxille are followed by three pairs of much larger appendages (mp'—mp°) exhibiting a very similar appearance, each consisting of a short basal part and two diverging unequal rami, the inner one (endopodite) forming a short incurved stem, the outer one (exopodite) a much larger, laterally extended natatory ramus. These three pairs of appendages, which are separated in the middle by a somewhat irregular flattened area (the sternal plastron), represent the maxillipeds in the adult animal. Behind them not even the slightest trace of any pedal buds is to be detected. The posterior division of the body, or metasome (figs. 1 & 2), is rather slender, being about twice as long as the anterior division, and is composed of six well-defined segments, the last of which is much the longest and very narrow. This segment passes without any intervening suture into the caudal plate. The latter is rather unlike that found in most other Caridean larvee and more resembles in shape that part in the protozoéa stage of Penwus. As in that form, it is cleft by a deep median incision into two slightly diverging lobes obtusely rounded at the end. Each lobe carries six finely ciliated setz of rather unequal length, the outermost one and the innermost but one being considerably smaller than the others. The 4th seta, counted from the outer side, is the longest, equalling in length the last segment to the bottom of the median incision. In some of the larve, which otherwise agreed with that here figured, a very small additional seta occurred inside the others on each lobe (fig. 12). On the anterior caudal segments slight traces of the epimeral plates could be detected, those of the 4th and 5th segments terminating in an acute corner. The ventral faces of the segments are somewhat convex ; but not the slightest trace of pleopoda is as yet observable. Structure of the Appendages. The antennule (fig. 4) are comparatively small, and each consists of a simple biarticulate stem extended forwards. The proximal joint is much the larger and represents the peduncle. It 1s, however, quite simple, without any trace of a subdivision and exhibits no armature whatever. The distal joint is much narrower than the proximal one, and also shorter, of oblong-oval PRAWNS FROM LAKE TANGANYIKA, 429 form, and movably articulated to the former. It carries on the tip three or four very delicate bristles, one of which seems to be sensory in character. This jot undoubtedly answers to the outer flagellum in the adult animal. Of the inner flagellum not the slightest trace is to be found in the present larva, whereas in all other larvee known to me it is at least indicated by a strong seta attached to the inner distal corner of the peduncle, The antennee (fig. 5), like the antennule, are each composed of two sharply defined joints, the proximal of which forms a thickish basal part imperfectly subdivided in the middle, and produced at the end inside to a short conical prominence indicating the place where subsequently the flagellum will be developed. The distal joint, representing the antennal scale, is considerably longer than the basal part and of narrow linear form, Its outer edge is perfectly smooth and terminates in a well-marked tooth- like projection, whereas the inner edge carries in its outermost part four strong ciliated sete attached to as many well-marked ledges and cur ved somewhat outwards. In most other Caridea known to me the antennal scale exhibits in the earlier stages of the larval period a rather different structure, its distal part being narrowly produced and divided by well-marked transverse sutures into several successive joints. Of such a subdivision not the slightest trace is found in the present larva, nor is the distal part of the scale produced beyond the tooth of the outer corner, this tooth in other Caridean larvee being formed only at a much ‘later period. The mandibles (fig. 6) have the inner, or masticatory, part somewhat expanded and divided by a slight median incision into two lobes; but neither of these lobes eehihis the slightest trace of any armature. The anterior mawille (fig. 7) ave trilobate, with the outermost lobe (palp) well defined as a distinct joint. The middle, or masticatory, lobe is somewhat more prominent than the innermost, or basal lobe. All three lobes extend obliquely inwards and have only very slight traces of marginal spines or setz. The posterior mawxille (tig. 8) have the form of oblong oval plates, the edges of which are irregularly indented or divided into a number of rounded lobules. ‘The two outermost of these lobules are separated by a somewhat deeper incision, and represent the one the exopodal, the other the endopodal part, the remaining three lobules of the inner edge representing the true masticatory lobes in the adult animal. As in the anterior maxille, only very slight rudiments of sete are present on the lobules. The three pairs of mawillipeds (figs. 9, 10, & 11), as above stated, are of a very similar structure and only differ in the relative size of the endopodite. The basal part consists of two imperfectly defined segments and is a little broader and more flattened in the Ist pair (fig. 9) than in the other two, The endopodite forms a slightly incurved cylindric stem and gradually increases in length from the Ist to the 3rd pair. In the Ist pair it is 430 PROF. G. O. SARS ON searcely longer than the basal part and divided only into three joints. In the other two pairs (figs. 10, 11) the middle joint appears faintly subdivided behind the middle. Very small sete in process of formation are seen on the terminal joint, and partly also on some of the other joints inside. The exopodite, which is movably attached to the outer distal corner of the basal part, is . in all three pairs of exactly the same appearance, forming a very . flexible, somewhat flattened stem with four long cilated sete at the end, two of them issuing from a minute apical joint. In the two posterior pairs another rather small seta is seen issuing inside at some distance from the end. Occurrence.—Several specimens of this peculiar larva, all closely agreeing both in size and structure, were obtained from four different samples. Two of these samples were taken at Niamkolo (S. end of lake), another at Mbete (likewise at the south end of the lake), and the fourth at Sumbu (8.W. of lake). ZOE Now 2e (Ele aiivain) The differences between this and the preceding larva are so conspicuous, that I think we are justified im assuming that it belongs to a different kind of prawn. It is of much larger size, and in some respects exhibits considerably more advanced development. Yet the imperfect structure of the oral parts, in connection with some other features, would seem to prove that it in reality represents a very early larval stage. The length of the specimen examined is about 1°60 mm., and the size of this larva is accordingly more than twice that of the preceding one, and nearly equals that indicated by Prof. Daday for the earliest observed stage (Huzoéa) of Caridina nilotica. The present larva cannot, however, by any means belong to that species, which does not occur in Lake Tanganyika, but must be derived from some other form of prawn, in which the ova are of a similar size to those in the said species. Consulting again the paper of Dr. Calman, we find that in this respect only one of the Tanganyika prawns would seem to come under con- sideration, viz., Caridella cunningtoni Calman, the ova of which are in reality much larger than in any of the other forms examined. Jam therefore led to the conclusion that the present larva in all probability may be an early stage of that form. As compared with the preceding larva, the body (PI. LVIII. figs. | & 2) appears rather short and stout, with the anterior diy1- sion considerably dilated and the posterior one less slender. The carapace is somewhat gibbously vaulted in its anterior part, and, as in the preceding larva, is slightly emarginated behind in the middle. At the antero-lateral corners a well-marked spine occurs; but this spine does not project laterally (fig. 1). Anteriorly the carapace is produced into a well defined, though quite simple narrow spiniform rostrum, which projects distinctly in front. PRAWNS FROM LAKE TANGANYIKA, 431 The eyes are of very large size and somewhat project beyond the lateral faces of the carapace (fig. 1). They are, however, like those in the preceding larva, still imperfectly separated in the middle and apparently quite immobile. The corneal part is well defined and contains a semi-oval assemblage of a dark pig- ment, from which numerous distinctly developed visual elements radiate. The ocellar lobe is partly visible in the dorsal aspect of the animal immediately in front of the eye-bases, but appears more distinctly on viewing the animal from the ventral face. As to the appendages, fig. 3 will give a general view of their form and arrangement in the present larva. On comparing this figure with fig. 3 on Pl. LVIL., it is at once seen that both the antennule and the antenne are considerably larger and also more advanced in development. On the other hand, the oral parts (anterior and posterior lips, mandibles and maxille) are very little different. The same is also the case with the three pairs of maxillipeds; but these appendages appear in the present larva more densely crowded and more remote from the hind limit of the mesosome, a considerable space being left behind them, which is oceupied by three additional pairs of limbs not found in the preceding larva. These limbs, representing the three anterior pairs of legs are, however, still only in process of formation, being quite immobile and folded beneath the mesosome. The metasome (figs. 1 & 2) is not fully twice as long as the anterior division of the body, and, as in the preceding larva, consists of six segments, the last of which is very narrow in its anterior part, but gradually expands distally, to form the caudal plate. The latter is comparatively smaller than in most other Caridean larvee, and looks rather different from that in the pre- ceding larva, not being cleft into two lobes, but only slightly emarginated behind in the middle (see also fig. 11). Each half of the plate carries the usual number of marginal sete, viz. 7, the outermost and innermost ones being rather small, the others nearly equal-sized and comparatively shorter than in the preceding larva. Of uropoda or pleopoda no traces are to be found. Structure of the Appendages. The antennule (fig. 4) have the peduncle rather prolonged and of cylindrical form, with a slight indication of subdivision into three joints. The outer flagellum, as in the preceding larva, consists of a single oblong oval joint carrying on the lip four unequal bristles, the innermost one distinctly ciliated. The inner flagellum, as in most other Caridean Zoée, is replaced by a strong ciliated seta attached to the inner distal corner of the peduncle. This seta, however, scarcely exceeds half the length of the peduncle, whereas in the earliest stage of Curidina nilotica it is, according to Prof. Daday, nearly twice its length. The antenner (fig. 5) exhibit the three principal parts well defined. ‘The basal part scarcely differs in structure from that in 432 PROF. G. 0. SARS ON the preceding larva ; but at its distal inner corner, in place of the simple conical projection found in that larva, a well-defined cylindric stem has been formed representing the flagellum. This stem is about the length of the basal part and exhibits a slight trace of subdivision behind the middle. It terminates in a spini- ocess from the base of which a rather long ciliated seta originates. The antennal scale is rather unlike that in the preceding larva, and agrees more in structure with that generally found in Caridean Zoée. It exceeds the flagellum by about one quarter of its length and is of narrow oblong form, slightly curved outwards. Its distal part is narrowly produced and divided by well-marked transverse sutures into three successive joints gradually diminishing in size. The scale carries inside and at the tip a regular row of eight ciliated sete and has, moreover, outside the tip a very small hair-like bristle. Another similar bristle is also seen originating from the outer distal corner of the form pr proximal joint. The mandibles and mawxille do not seem to exhibit any essential difference in their structure from those in the preceding larva, and are scarcely as yet functionally developed. The three pairs of mawillipeds (figs. 6-8) likewise exhibit much the same structure, though the difference in size of the endopodite is still more sharply marked than in the preceding larva, that of the Ist pair (fig. 6) being extremely small as compared with those of the two succeeding pairs, the size of which is also somewhat unlike. Of the three pairs of imperfectly developed appendages suc- eceding the maxillipeds the two anterior ones (fig. 9), representing the developing chelipeds, ave bifid or cleft into two nearly equal digitiform rami, one of which is the endopodite, the other the exopodite. ‘The posterior pair (fig. 10) are still undivided and shorter than the two anterior ones. They represent the first pair of pereiopoda, the last two pairs being not yet formed. All these appendages exhibit a very simple structure and are filled up with indifferent cells, no articulation or setous armature being observable. Oceurrence.—Of this larva also several specimens, exactly agreeing with each other, were found. They occurred in two of the samples, the one taken at Niamkolo, the other at Mbete, both located at the south end of the lake, Larva No. 3. (Pl. LIX.) This larva represents a much more advanced stage than the 1g ones, and therefore can be determined with more T think that I am right in considering it as the the so-called Mysis-stage, of Limnocaridina parvula Calman. The solitary specimen which has come under my notice, was found in a sample which contained several young specimens of that prawn, and both as to size and general two precedir certainty. last larval stage, PRAWNS FROM LAKE TANGANYIKA, 433 appearance there was a striking resemblance between them and the present form, the larval character of which, however, is at once apparent by the presence of well-developed natatory exopodites on all the legs, except the last pair. The length of the specimen examined was 2°60 mm., measured from the tip of the rostrum to the end of the caudal fan. The general form of the body (Pl. LIX. figs. 1 & 2) is rather slender and exhibits the characteristic Caridean aspect, the meta- some being well developed and distinctly bent in the middle, The carapace has the dorsal face somewhat flattened, with a faint cervical suleus in front of the middle and the posterior edge emarginated dorsally, exposing a part of the last segment of the trunk. At the antero-lateral corners a small spine is seen, somewhat remote from the margin. The rostrum is very small and still quite simple, without any trace of denticles. The eyes are comparatively large and project considerably beyond the lateral faces of the carapace. They ave distinctly separated in the middle and freely mobile, being attached to each side of a narrow transverse eminence located just beneath the base of the rostrum. The corneal part is well defined from the thickish pedicles, and has the visual elements very distinct. The dimbs of the anterior division are complete in number, five pairs of true legs being present. All these, except the last pair, carry outside natatory exopodites of the same structure as those on the maxillipeds, making in all seven pairs of such appendages. The metasome is more than twice as long as the anterior division and much more powerfully built than in the two pre- ceding larve. On the five anterior segments the epimeral plates are distinctly developed, though they do not as yet extend beyond the ventral face of the segments. The 31d segment is more vaulted than the others and has the posterior edge somewhat bowed in the middle, advancing over the base of the succeeding segment. The 6th segment is very narrow, and considerably longer than the two preceding segments combined. It carries at the end a well-developed caudal fan, consisting of a median piece (telson) and two movable lateral appendages (uropoda), each divided into two setiferous lamelle. he five preceding segments earry each a pair of ventral appendages (pleopoda) exhibiting all the chief parts found in the adult animal, but these appendages seem not yet to have entered into function as swimming organs. Structure of the Appendages, The antennule (fig, 3) have the peduncle divided into three well-defined joints, the first of which is much the largest and exhibits outside near the base a lamellar expansion terminating in a small anteriorly curving denticle, Some very delicate bristles are seen issuing from the outer distal corner of this and the succeeding joint, and from the inner corner of each of the two outer joints a somewhat stronger plumose seta originates, pointing Proc. Zoo. Soc,—1912, No, XXVIII, 28 434 PROF. G. 0. SARS ON straight forwards. Both flagella are distinctly defined and of about equal size. They are, however, still rather short, scarcely exceeding half the length of the peduncle, and do not exhibit any trace of subdivision. At the tip each flagellum carries a bundle of small bristles, and on the outer flagellum, moreover, two bundles of delicate sensory filaments have developed, attached to well- marked ledges of the anterior margin. On the antenne (fig. 4) the scale is rather large and oblong- oval in form, with the outer edge straight and perfectly smooth, terminating in an acute tooth-like projection. The distal part of the scale is obliquely truncated and projects somewhat beyond the tooth of the outer edge. It is, like the inner slightly convex edge, fringed with a regular row of slender ciliated sete, about sixteen in number. The flagellum considerably projects beyond the scale and points straight forwards. At its base a short joint has been cut off representing the peduncular part. The terminal part of the flagellum is still quite simple, cylindric, and without any trace of subdivision. The mandibles (fig. 6) have the cutting-edge divided into a number of small denticles, behind which some minute bristles are attached. The molar tubercle may also be distinctly traced. The anterior maaille (fig. 7) exhibit a structure nearly agreeing with that found in the adult animal, the middle, or masticatory lobe being rather strong and securiform in shape, with a row of well-developed denticies along the straightinner edge. ‘The very small terminal lobe, representing the palp, is attached outside the masticatory lobe to a well-marked ledge, and carries on the tip three rather slender bristles. The basal lobe is cordiform and fringed with ciliated sete. On the posterior maxille (fig. 8) the exopodal plate is now well defined and mobile, its anterior part bemg edged with slender finely ciliated sete, and the posterior part exserted to a narrow lappet carrying on the tip a few sete. Of the lobes belonging to the endopodal part the outermost one is cut off as a distinct joint, representing the rudimentary palp or endopodite proper ; the remaining three lobes are edged with well-developed spines and setee, and constitute the masticatory part of the maxilla. The three pairs of mamillipeds (figs. 9-11) are less conspicuously transformed, though the 1st pair (fig. 9) by the greater size of the basal part and the considerable reduction of the endopodite somewhat approach the structure of these appendages in the adult animal. The characteristic difference between the two posterior pairs observed in the adult animal is, however, not yet apparent, the endopodite being in both (figs. 10 & 11) of a very similar appearance and agreeing with that found in earlier larval stages, with the only exception that the sete clothing the joints are more fully developed. The exopodites in all three pairs are unchanged, acting still as natatory organs. The two anterior pairs of legs, or the chelipeds (fig. 12), are of exactly the same structure, the endopodite of both terminating in . PRAWNS FROM LAKE TANGANYIKA. 435 a didactylous hand. They are, however, still comparatively short, and do not exhibit the full number of joints, the ischial joint being not yet separated from the meral one, The hand js also imperfect in so far as none of the fingers is as yet mobile, Both fingers are clothed at the obtuse extremity with a few very slender bristles, and similar bristles are also attached inside the other joints. The natatory exopodite is about the Jength of the endo- podite, and of exactly the same structure as in the maxillipeds. The three succeeding pairs of legs, the pereiopoda (figs. 13 & 14), are a little longer than the chelipeds, and have the endopodite of cylindric form and more or less curved, being composed of four well-defined joints, The last joint, or dactylus, is conical in form and carries on the tip a slender spine accompanied by a few bristles. Similar bristles, partly of considerable length, are also attached to the inner side of the other joints. The two anterior pairs (fig, 13) carry well-developed natatory exogpodites of the same structure as those on the chelipeds, whereas the last pair (fig, 14) do not exhibit any trace of such appendages. The pleopoda (figs. 15 & 16), as in the adult animal, consist each of a somewhat flattened, oblong quadrangular basal part and two terminal, lanceolate lamellz, apparently answering to the endo- podite and exopodite. ‘These lamellze, however, still only exhibit very slight traces of marginal setz in process of formation. On the Ist pair (fig. 15), as in the adult animal, the inner lamella is rudimentary ; on the other pairs (fig. 16) it is well developed, though somewhat shorter than the outer one, and carries inside, at some distance from the base, a small digititorm appendage. The telson (fig. 17) has the form of an oblong quadrangular plate, well defined from the last caudal segment, and slightly exceeding half its length. It is armed at the nearly transversely truncated extremity with eight spines of unequal size, the two outermost being much the longest and somewhat diverging, the two innermost and the outermost but one on each side rather small, The uwropoda (fig, 17) have the outer plate of a shape very similar to that of the antennal scale; the inner one is a little shorter and lanceolate in form, Both plates are fringed with ciliated sete and extend somewhat beyond the telson. Occurrence,—The solitary specimen described above was found in a sample taken at Sumbu (S.W. of lake). In the same sample also occurred a few yery young specimens of Limnocaridina parvula Calman, Youne Prawn IN THE Ist PostLaARvAL Stace. (Pl. LX.) There cannot, I think, be any doubt that the speeimen described below and figured on the accompanying plate is referable to the same species as the preceding larva, and accordingly is a developing stage of Limnocaridina parvula Calman. The simi- larity in the general aspect is very striking, and the difference in 28" 436 PROF. G. O. SARS ON size is so slight that we have every reason to believe it to represent an immediately succeeding stage. But, whereas in the preceding stage the larval characters were very apparent, they are wholly lost in the present specimen, which accordingly has entered the postlarval period, representing here in all probability the very first stage. The length of the specimen examined measures 2°70 mm., and thus very little exceeds that of the preceding larva. The adult ovigerous female of the present species attams, according to Dr. Calman, a length of 6°70 mm. ; The general form of the body (figs. 1 & 2) is very slender, even more so than in the preceding stage. The carapace is of a quite similar shape, and the rostrum is very short and spiniform; but on its upper edge three or four small denticles have appeared (fig. 2). The eyes considerably project laterally and exhibit a somewhat, fusiform shape, their pedicles being conspicuously dilated in the middle. The corneal part, on the other hand, appears somewhat less expanded than in the preceding stage. The metasome is more powerfully developed, and exhibits the Caridean bend on the middle very distinctly (see fig. 2). The epimeral plates of the five anterior segments are deeper, extending slightly beyond the ventral faces of the segments. On the appendages several changes have taken place, the most conspicuous of which are the complete loss of the natatory exopodites on the legs and the reduction of those attached to the maxillipeds, the natatory function being now wholly transferred to the metasome and more particularly to the pleopoda. Structure of the Appendages. The antennule (fig. 3) have the joints of the peduncle more sharply defined and several additional plumous sets have appeared inside the joints. The flagella are still rather short, but on both a distinct subdivision has taken place, the inner one being com- posed of three, the outer of four well-defined joints. On the outer flagellum, moreover, a short uniarticulate appendicular ramus has developed from the end of the second joint, carrying on the tip a bundle of sensory filaments. On the antenne (fig. 4) the scale is nearly unaltered, whereas the flagellum has considerably increased in length, being now fully twice as long as the scale. It is, moreover, divided into several joints, the outer of which are very sharply marked off from each other and provided with small hair-like bristles, whereas the proximal ones are still imperfectly defined. The flagellum also appears to be freely mobile in relation to the peduncular part, as it is found in some cases extended forwards, in other cases more or less obliquely backwards (figs. 1 & 2). The mandibles (fig. 5) agree on the whole in their structure with those in the preceding stage, though the molax prominence PRAWNS FROM LAKE TANGANYIKA. b 43 appears more distinctly defined and exhibits a well-marked triturating surface. The maxilla (figs. 6 & 7) scarcely differ from those in the pre- ceding stage, except in a somewhat richer supply of marginal spines and sete. The mamillipeds (figs. 8-10), on the other hand, have been con- spicuously transformed, and now look very dissimilar. In the Ist pair (fig. 8) only a slight rudiment of the endopodite is left, and the exopodite also is considerably reduced and apparently quite immobile, without any sete at the tip, and having the distal part curved downwards. On the 2nd pair of maxillipeds (fig. 9) the endopodite bas assumed the characteristic securiform shape observed in the adult animal, the outer two joints forming to- gether a broad plate folded upon the proximal part and armed at the inner edge with a number of spiniform anteriorly curving sete. On the 3rd pair of maxillipeds (fig. 10) finally the endo- podite has preserved its pediform shape, but is considerably prolonged, forming a nearly straight cylindric stem almost twice as long «s the exopodite. The latter, as in the preceding pair, is extended straight anteriorly, and appears to be very little mobile. The chelipeds (fig. 11) have increased in length, and now exhibit the full number of joints. On the hand, one of the fingers (dactylus) has been well defined ab the base, and connected with the hand by a very mobile articulation ; on the tip of each finger a short claw-like spine has developed in addition to the bristles, the number of which is considerably increased. The sete on the other joints are, however, shorter and less numerous than in the preceding stage. Outside the basal part a very small and irregular protuberance is seen, indicating the place where the exopodite has originally been attached. The pereiopoda (figs. 12 & 13) are somewhat longer than the chelipeds and quite normal in structure. The dactylar joint nearly agrees both in shape and armature with that in the adult animal, as described by Dr. Calman. Outside the basal joint of the two anterior pairs (fig. 12) a minute protuberance quite similar to that occurring in the chelipeds is seen, indicating the original presence of exopodites on these legs. In the last pair (fig. 13) no trace of such a protuberance is to be detected. Above the bases of the legs, except the last pair, and covered by the lateral parts of the carapace, the gills have developed, forming on each side a regular series, as indicated in fig. 2. The pleopoda (fig. 14) are now freely mobile and have the terminal lamelle fringed with long ciliated sete. The number of these sete is, however, as yet very limited, only eight being counted on the outer lamella and six on the inner. All these sete exhibit close to the base a very conspicuous joint. The telson (fig. 15) does not differ much in shape from that in the preceding stage; but the number of apical spines has diminished, only five such spines being present. On the other hand, three pairs of lateral denticles have appeared, the outer- 438 PROF. G. O. SARS ON most one occupying the outer distal corner, the other two placed at some distance from each other and more dorsally. The wropoda only differ from those of the preceding stage in a somewhat richer supply of marginal sete. Occurrence.—The above-described specimen was found in the same sample as the preceding larva, and was associated with three other somewhat larger specimens. Moreover, young specimens of the same species occurred in two other samples, the one taken at; Mbete (S, end of lake), the other at Karema (KE. shore of lake). In the latter sample numerous specimens were present. GENERAL REMARKS. Among the Macrura inhabiting fresh water, so far as I know, the genus Caridina is the only one in which a true metamorphosis has been found to occur. In the other forms the postembryonal development is either direct, as in Astacus, or at least exhibits only very slight traces of a metamorphosis. This difference in the development, according to the medium, may even be found in a single species, viz., in the case of Palemontes varians. ‘The typical form of this species, found in salt or brackish water, passes through a quite normal metamorphosis; whereas in the variety inhabiting purely fresh water the larval development 1s much abbreviated, the young leaving the egg with all the append- ages present, except the uropoda. A similar suppression of the metamorphosis is certainly also observed in some of the marine forms; but these are, as a rule, only such as inhabit very deep water. In shallow-water forms, on the other hand, a compli- cated metamorphosis is always found to prevail. In most cases the relative size of the ova, borne by the female beneath the metasome, will be suggestive as to the decision whether the metamorphosis in the observed form is complete or suppressed. If the ova are very large and few in number, this is an infallible sign that the metamorphosis is incomplete or quite absent. — On the other hand, the presence of very small and numerous ova points to the assumption that the young hatch in an imperfect larval condition, and of course must pass through a more or less complicated metamorphosis before reaching maturity. In most of the prawns inhabiting Lake Tanganyika, as established by the measurements given by Dr. Calman, the ova are of un- usually small size, and from this fact alone it could be inferred that a true larval development must be present. This has indeed been fully confirmed by the investigations here published, and in one case it has, moreover, been proved that the larvee, on escaping from the ova, exhibit a still simpler and more primitive structure than found in any other known form of this group. A very peculiar feature, exhibited by the two Zoéx described in this paper, remains to be mentioned, viz., the very rudimentary aud as it were embryonic appearance of the oral parts (mandibles and maxille). In all free marine larve belonging to the present “PRAWNS FROM LAKE TANGANYIKA. 439 group, even immediately after hatching, I have found that these parts, though more or less differing in structure from those in the adult animal, yet at all events are functionally developed. This cannot, however, by any means be said to be the case in the two Z“oée here under consideration. On the contrary, it is evident, both from the very imperfect structure of these parts and their position in relation to the mouth, that they cannot possibly act as true masticatory organs. The larve, of course, in these early stages are quite unable to feed in the ordinary manner, and must be assumed to subsist exclusively on the nutritive yolk still left within the body. It seems to be very difficult to account for this anomalous case; but a hypothesis may perhaps be set forth. I suggest the possibility that in the lake there is scarcity of that kind of food which would be suitable to the larve in this early period, and perhaps also the absolute absence of Cladocera in this lake may be explained in a similar manner. In the more advanced stages, when the oral parts have been more fully de- veloped, the larve in all probability feed upon the small Copepoda which abound in the lake. EXPLANATION OF THE PLATES, Pr. LVI. Recently hatched larva (Euzoéa) of ? Limnocaridina spinipes Clm. 1. Dorsal view of the larva. 2. Same larva, viewed from left side. 3. Anterior division of the body, viewed from the ventral face, and more highly magnified. The three posterior limbs on left side are not fully drawn, in order to show those occurring immediately in front of them more distinctly. 41, antennule ; 47, antenne ; oc, ocellar lobe; H, hypo- stome; DL, anterior lip; J£, mandibles; /!, posterior lip; m/, anterior maxilla; m?, posterior maxilla; Jp!-Mp*, maxillipeds of 1st to 38rd pairs. 4, Left antennula. 5. Left antenna. 6. Inner part of a mandible. 7. Anterior maxilla. & 9 10 Fig. . Posterior maxilla. . Maxilliped of 1st pair. . Maxilliped of 2nd pair. 11. Maxilliped of 3rd pair. 12. Left half of caudal plate. Px. LVILI. Early larval stage (Zoéa) of ? Caridella cunningtoni Clm. . Dorsal view of the larva. . Same larva, viewed from left side. Anterior division of the body, viewed from the ventral face, and more highly magnified. The three maxillipeds on left side are omitted in order to show the maxillw# more distinctly. . Antennula. . Antenna. . Maxilliped of 1st pair. . Maxilliped of 2nd pair (exopodite not fully drawn). . Maxilliped of 3rd pair. 9. Developing cheliped. 10. Developing pereiopod. 11. Caudal plate. Cobo DO OTHAS 440 Fig. 25. The Classification, Morphology, and Evolution of the By Herpert L. Hawkins, M.Sc., F.G.S. ; Lecturer in Geology, University College, Reading *. Within the limits of a single class, it would be difficult to find greater contrasts than those which distinguish the various orders OMAN WN Echinoidea Holectypoida. MR. HERBERT L. HAWKINS ON Pu. LIX. Last larval stage (Mysis stage) of Limnocaridina parvula Clm. Dorsal view of the larva. Same larva, viewed from left side. . Antennula. . Antenna. . Anterior lip. . Right mandible and masticatory part of left. . Anterior maxilla. . Posterior maxilla. . Maxilliped of 1st pair. 10. Maxilliped of 2ud pair. . Maxilliped of 31d pair. 2. Cheliped (exopodite not fully drawn). 13. Pereiopod of 1st pair (exopodite not fully drawn). 4, Pereiopod of last pair. . Pleopod of 1st pair. . Pleopod of 2nd pair. . Extremity of last caudal segment, with telson and left uropod ; Pu. LX. First post-larval stage of Limnocaridina parvula Clu. . Dorsal view of the specimen. . Same specimen, viewed from left side. . Antennula. Antenna. . Mandible. . Anterior. maxilla. . Posterior maxilla. Maxilliped of 1st pair. . Maxilliped of 2nd pair. . Maxilliped of 3rd pair. . Cheliped. . Pereiopod of Ist parr. . Pereiopod of last pair. . Pleopod. . Outer part of telson, [Received November 16, 1911: Read March 5, 1912.] (Text-figures 54-60.) ContvTENTS. I. Introduction ..... SPAR RA Sirs came sane 6 hie II. History of Past Claseif cation. .c<...dteaod cates ene III. The Revised Classification.. IV. Comparative Morphology ...... V. The Internal Evolution of the Group .. shendeaiaues eet WileeihverExternalavelationshup samcieeeeeateet ere reee ee eeeece ere Eee VII. Summary VIII. List of Literature « consulted .. I. Lytropvuction. dorsal view. * Communicated by Dr. Henry WoopwarpD, F.R.S., V.P.ZS. SEA-URCHINS. 44} of the Echinoidea. To a casual observer, unacquainted with the anatomy and embryology of the forms, such genera as Cidaris and Echinocardium would seem to represent two absolutely different “kinds” of animals. Moreover, search as he might among the Kchinoids of the present day, he could find no types that would effectively bridge the gulf that separates the Regular from the Irregular Sea-Urchins. All the Regularia have thick tests, built on a radially symmetrical plan ; possess a strong jaw-apparatus ; and are armed with stout, often very long, radioles. On the other hand, most of the Irregularia have thin tests, bilaterally sym- metrical; have no jaws; and are covered with small, almost hair-like radioles. Even those forms, the ‘ Cake-Urchins,” which show a radial symmetry and possess jaws, have other characters which render them very different in appearance from the Regular Echinoids, And again, from an anatomical study of Jiving forms alone, although a similarity of structure sufficient to warrant their inclusion in the same order of the Echinoderma might be found, no certain clues as to the relation of the two types to one another could be discovered. Even ontogenetic evidence is lacking to a considerable degree, for the peculiar larval life led by Echinoids has tended to neutralise the effect of recapitulation. At this point, where Zoology in its narrower sense fails, Paleontology can supply the connecting links between such different forms as a Cidarid and a Spatangid ; and of these links, the majority are to be found in the group which forms the subject of this research. The order Holectypoida arose soon after the commencement of the Jurassic period, and became entirely extinct before the close of the Mesozoic era. During its existence it gave rise to forms which, by stages so gradual as to be hardly distinguishable, laid the foundations of all the great groups of Irregular Echinoids that are living to-day. It is the purpose of this paper to indicate in outline the processes through which the specialization of Clypeastroids, Spatangoids, and ‘ Cassidulids ” was achieved. When P. M. Duncan (44)* wrote his classic “ Revision of the Genera and great Groups of the Echinoidea,” there existed “much diversity of opinion regarding the nature of the peri- gnathic girdles and jaws of some genera” (¢.c., p. 135) of the Holectypoida, the most primitive group of the Irregular Echinoids. As Duncan’s system of classification was based to a very large extent on the varying characters of these structures, it naturally resulted that in the case of the Holectypoida and their allies the grouping of genera into families, or even into larger groups, was somewhat tentative. It is only necessary to remark that jaws are now known to have existed in two genera, in which their presence was denied by Duncan, to show that a revision of the classification of the group is required. * Where a number in brackets follows the name of an author, the full title of the paper referred to will be found under that number in the chronological list of literature at the end of this paper. 449, MR. HERBERT L. HAWKINS ON However, the difficulties of a systematic grouping of the primitive gnathostomatous Irregularia are not removed, or even lessened, by the additions that have been made to our knowledge of their comparative anatomy. Rather are they increased, for the establishment of affinities between genera leads to greater complexity of classification than that of differences. The Holectypoida are an annectant group, the history of whose evolution is so intimately interwoven with that of the early stages of most of the Irregular orders and suborders, that to frame a purely natural classification would need an impracticable plasticity of diagnoses. This systematic trouble is, however, more than compensated by the phylogenetic evidence that it indicates. In the course of the following work I have endeavoured, while recasting the artificial classification of the systematist, to lay emphasis on relationships rather than on contrasts, and to show the position occupied by the Holectypoida at the foundation of the varied structures of the Irregular Echinoids. The present essay is the outcome of several years of study of the group, and contains a summary and amplification of a series of papers (see list at end) that have been published in the ‘Geological Magazine.’ I have thought it unnecessary to repeat here many of the details described in those papers, so that, except where corrections or additions have been possible, the results arrived at in them are taken for granted. There are, however, descriptions of a number of features that find a place here which were not dealt with in the shorter papers given here. After a brief sketch of the history of the classification of the group, the revised scheme is put forward. This is followed by a morphological comparison of the genera within, and of some genera without, the boundaries of the order; and lastly, the directions of evolution thus indicated are discussed. II. History or Pasv CLassivicaTion. This part of the paper does not pretend to be a complete account of all the past work that has been done on the group, but it is a summary of the chief systems of classification that have been proposed up to the present time. The history of the group may be said to date from 1734, when Klein, in his ‘ Naturalis dispositio Echinodermatum,’ distin- guished “ Sectio I, /ibula,” from the rest of the “ Hchini catocysti circulares.” The section was diagnosed as follows :—“ Echinos fibulares dicimus Catocystos circa Basis circularis peripheriam Anum, Os in medio aperientes.” He included two genera only in the section, Conuluws and Discoides, both of which are recog- nized to-day, and have been associated with one another in most of the systems of classification. Klein apparently did not know of any of the other genera included among the Holectypoida in the present paper. SEA-URCHINS. 443 The classification adopted in 1840 by L. Agassiz, in his ‘Catalogus systematicus,’ was in many ways of less value than that of Klein; for he grouped together, under the heading of ‘“Clypeastroidee,” all the non-Spatangid Irregular Echinoids. However, Desor, in the sequel to that Catalogue (11) showed that a more detailed system of subdivision was practicable, and founded the first definite scheme of the classification of the group. The “tribu” of the ‘“ Galérites” was regarded as a division of the “ Clypéastroides.” It contained the following g ‘ara- tomus, Discoidea, Echinoneus, Galerites, Globator, Holectypus (as a subgenus of Discoidea), Hyboclypus, Nucleopygus, Pygaster, and Pyrina. This list of genera contains a very natural grouping of all those Irregular Echinoids which have simple, apetaloid ambulacra. That, however, is almost the only trait that could associate them, and in Car ee at least, the simplicity of the ambulacra is not absolute. In the ‘ Catalogue raisonnée’ (1847) Agassiz and Desor retained this grouping of the genera in its entirety, but rearranged the position of the “tribu” as a whole. It appears as the family Echinoneidz, a section of the Cassidulide. This change was at once an advance and a retrogression. It applied to the family a name under which some of the genera have remained since that time, but by associating the whole series with the Cassidulids, it tended to obscure the importance of the gnatho- stomatous char acter of many of the genera. In the Synopsis, Desor (21) retained the division under the name of Galeridées, and added large numbers of genera to the list. He recognized, however, the fundamental importance of the presence of jaws in determining the systematic position of a genus, and so separated the Galeridées into two groups. Of these, the fir st, or “Galeridées proprement dits,” contained Aeey genera with j jaws (or rather, supposed to possess them), while the second, the “‘ Echinonées,” included Hehinoneus only. The first group contained all the genera of the ‘“Galérites ” of 1842, except Caratomus and Echinoneus, and there were added the then newly described genera dAnorthopygus, Asterostoma, Desorella, Galero- pygus, Pachyclypus, and Pileus. It is curious that Desor should have taken it for granted that all these fossil genera were gnatho- stomatous, for he cannot have had any positive evidence to work upon in the majority of cases. In 1857 Pictet, in the second edition of his ‘ Paléontologie ’ (22), reverted to the method of er ouping originated by Desor in 1842 changing the word “Galérites” to the subordinal term “ Galeri- tiens,’ and adding the then recently described Desoria. One year before the appearance of Desor’s Synopsis, Wright (20) had grasped the essential differences which divided the “ Galerites”” into two sections. He founded the family of the Kchinoconidee, which contained Discoidea, Echinoconus (the Galerites of most previous authors), L/olectypus, Hyboclypus, and 444 MR. WERBERT L. HAWKINS ON Pygaster. He contrasted this family with the Echinoneide, in which he placed Hehinoneus, Pyrina, and several other genera. This was the first time that the presence of jaws was treated as an essential feature in the classification of the group. Wright's system of classification was adopted for many years by almost all the Echinologists who dealt with the group, although slight changes in the generic personnel of the Echinoconide were introduced. Cotteau (28) removed Hyboclypus, with good reason, from the family, and added the genera (unknown to Wright in 1856) Anorthopygus and Pieus. The compact group thus determined, bound together by the characters of a short and accurate diagnosis, became generally accepted. Lovén (31) worked on this classification as a basis, and Wright (82) agreed with Cotteau’s modifications. Perhaps no gurer indication of the natural character of the grouping could anywhere be found than in the fact that Pomel (87) was unable to find any cause for more than internal changes in the family. With a subordinal rank within the group of Gnathostomes Clipéiformes, Pomel placed the section Galérides. This section he subdivided into two chief families, the Echinoconidés and the Piléidés. The latter family was further separated mto two sub- families, the Discoidiens and the Pygasteriens. Although many new ‘‘generic” terms were introduced, no forms were included among the Galérides that were not previously classed with the Echinoconide. The separation of the Hchinoconus-group from the other genera was natural. In the Piléidés, the first group was simply the original genus Discoidea of Agassiz in a dis- membered state, while tlie second group included the same author’s early conception of the genus Pygaster, The classification of Pomel was therefore, in this group, quite orthodox, a condition of affairs sufficiently surprising in view of the great changes he roposed in the arrangement of many of the other groups. Tn 1889, Duncan (44), who expressly dissociated himself from Pomel’s views of the relative importance in classification of various structures, published the invaluable Revision of the renera, etc. of Echinoidea. In this work, he realised the great importance of the Holectypoida as an annectant group. So thoroughly intermediate in its characters was the group that he definitely stated that his classification was artificial, and as such tentative. The Holectypoida received the rank of an Order, equivalent in importance to the Clypeastroida or the much larger groups of the Diademoida and Spatangoida. It was chiefly on the peristomial and jaw-structures that Duncan classified the group, and on that account it was particularly unfortunate that he should have had such a fixed belief in the absence of jaws in some genera in which they have since been discovered. Curiously enough, although, in the same year as the publication of the Revision, he definitely stated his disbelief m the existence of jaws in Discoidea (45), he allowed that genus to SEA-URCHINS. 445 find a place among the Holectypoida, while Lehinoconus was banished to the Echinoneidze among the Spatangoida. the adoral than the adapical series is placed slightly nearer transverse margin of the plate. All the other tubercles, of which Text-fig. 58. oe Soo sa - : Oe OC SU OVO) So ais Pie tans pea eee é 2 ae wo 8s 90009 showing the third plate above the ambitus in A. Pygaster sens. str.- . Holectypus (hemisphericus) ; C. Holectypus (depressus) ; D. Discoidea ; Diagram — we E. Galeropygus ; F. Anorthopygus ; G. Conulus. Figs. H & K are side views of primary tubercles in Pygaster and Conulus respectively. great numbers may occur in the later genera, are developed in recognizably vertical series. When their number becomes great, a natural tendency to slight irregularity appears, but this is never ATA MR. HERBERT L. HAWKINS ON sufficient to mask the plan of the tuberculation. Ivrregularity generally consists of either the suppression of a member of a series on one plate (a feature often seen, even in the primary row, in Hchinus), or its replacement by two tubercles. The Holectypoida are peculiar among Irregular Echinoids in retaining throughout life the unituberculate plates and the vertical arrange- ment of the tubercles. Only the Echinoneidee show any similar plan, and in them it is very much obscured by irregularity of development. Some forms of Pygurus (e.g., P. blumenbachi) have one or more unituberculate plates at the adapical extremities of their interambulacra, but this retardation of development is obviously due to the considerable narrowing of the plates caused by the expansion of the ambulacral petals. However, most, if not all, of the Irregular Echinoids whose post-larval development has been studied, show a unituberculate stage. This is notably the case in Hchinolampas (see Agassiz, 30). _ The tubercles of the additional series* which develop on the interradial tracts are at first situated each in the middle line (in a vertical sense) of the plates. This results in a transverse line of tubercles extending between the main series and the inter- radial suture. The concentric arrangement thus caused charac- terizes Pygaster sens. lat., Holectypus sens. lat., and Discoidea. It seems somewhat irregular in the case of Pilews, and is definitely absent in Anorthopygus and Conulus. In these two genera the tubercle series of the interradial tracts appear near to the adapical and adoral margins of the plates alternately, thus giving an oblique arrangement (sloping interradially and adorally) to the tubercles in the complete interambulacrum. A similar arrange- ment to this affects the adradial tubercle-series in all the genera of the group. The oblique setting of the tubercles results in a much more uniform and packed tuberculation over the whole area than exists when the interradial series are transverse. The closeness of the arrangement is increased by the doubling of many of the tubercles in Conulus ; so that, instead of two tubercles, three or even four are concerned in the composition of the oblique line on each plate. The complexity of arrangement, coupled with a homogeneity of character, of the tubercles, which was thus slowly obtained during the course of evolution of the Holectypoida, was rapidly developed, and carried to a further degree, by the earliest of the non-Holectypoid Echinoids. The species of Galeropygus from the Lias show typically the bewildering profusion of small tubercles which characterize the interambulacra of all the Nucleolitide, ‘‘ Cassidulidee,” Clypeastroida, and early Spatangide. Only the Kchinoneide seem to preserve a Conulus-character in their tuberculation, and in them it becomes so irregular as to be hardly appreciable except in the newest formed plates. The peculiar sunken supernumerary tubercle of some of the adapical interambulacrals of Holectypus depressus from the Corn- brash recently described (Hawkins, 67) is without a parallel SEA-URCHINS, 475 among the other members of the order, Although suggesting a comparison with the large interpetalous interambulacral tubercles of such a genus as Hupatagus, it seems to be a specific character of no genetic value. 3. The Miliary Granules. In Pygaster, and to a less degree in Holectypus, the granulation shows a “ Regular ” affinity in being grouped around the primary tubercles to form scrobicular rings. This circular arrangement is not retained after the Jurassic period. In Holectypus, especially in H. depressus, the scrobicular miliaries on the adradial tracts of the plates near the peristome are often guttate in form. In Macropygus and Anorthopygus the large size of the scrobicules of the primary tubercles leaves little room for miliaries, but those which exist do not appreciably group themselves around the primaries. In Discoidea and Cenholectypus, and to a slight degree in Holectypus sens. str., rows of granules radiate from the central primary tubercle, maintaining a more or less transverse direction, to reach the adradial and interradial margins of the plate. In the genus first named these linear rows of granules become interspersed, near the ambitus, with additional tubercles. In Conulus the granulation is apparently without a definite system of arrangement. The granules are sunk slightly below the level of the test on the adapical surface, being enclosed in minute pits. On the adoral surface they regain their projecting character, and often occupy broad bands, slightly elevated, which correspond in position with the transverse sutures of the plates, Ea ives Kia dia oullers: Our knowledge of the acanthology of the Holectypoids is fragmentary and inadequate. Enough is known, however, to show that there exists a considerable uniformity in the character of the radioles throughout the group. Wright (20) has described the primary radioles of Pygaster, in the species semisulcatus and (Macropygus) morrisii. For both he uses almost the same words— short, needle-shaped bodies with fine longitudinal lines on the stem. I have not seen any specimens in which they are preserved. In the case of Holectypus there is a specimen of /. depressus (from the Inferior Oolite of Cheltenham) in my collection which retains a considerable number of radioles on both the adapieal and adoral surfaces. Wright (¢.c.) describes them in the same species. The primaries of the upper surface are very short and slender, with blunt tips. Those of the adoral surface were apparently quite long, and but slightly tapering. The collars of the adoral radioles are prominent, and often very oblique. The shafts of both sets of radioles are longitudinally fluted with closely-set ribs. The miliary granules support spines of a similar character to the adoral primaries, but far more minute, so that Wright’s descrip- tion of them as “ hair-like” is accurate. 476 MR. HERBERT L. HAWKINS ON I have been unable to find any record of the preservation of radioles in Discoidea. In Conulus the primaries are very much like those of the adoral surface of Holectypus in shape and ornament. The miliaries support curiously. blunt prominences, which are usually preserved im situ, but are very easily rubbed off by too vigorous development of the specimen. These blunt spines were figured by Forbes (14), who also gave a drawing of a curious body that he regarded as a pedicellaria. The characters of the miliary spines suggest a comparison with the calcareous supports of pedicellariz ; but if they all had this function, the number of those organs would be extraordinarily great in proportion to the radioles. Nothing seems to be known as yet of the microstructure of the radioles of any genera of the group, as Hesse (51) did not choose an Holectypoid for his researches. The slight progressive change traceable in the primary radioles seems to lead merely to an increase in the length, and perhaps in the slenderness, of their shafts ; while,as would be expected from the difference in size of the tubercles on the two surfaces of the test, the adoral radioles become proportionately longer than those of the adapical surface. G. Internal Buttresses. The difference in form which makes so violent a contrast between a Scutella and an Hchinus must result ina corresponding difference of resisting power against the pressure of the waves. As both types of Echinoid may live between tide-marks, where the violence of the waves is most felt, they both have the same forces to repel. A spherical body such as that of an Hehinus, or even a hemi- spherical one, like that of an Holectypus, could easily ward off the blow of a breaking wave, in the same manner as a Patella does. But a flat test, such as that of a Scutellid, would offer a blank resistance to the waves, and, if hollow, would almost certainly be crushed. For this reason, the few groups of the Irregular Echinoids that frequent the exposed littoral habitat so characteristically occupied by the Regular forms, strengthen the resisting power of their tests by the development of massive calcareous buttresses within. Practically the only Irregular forms which live openly on the shore at the present day are the Clypeastroida. It becomes, therefore, a point of especial interest to find the beginnings of internal supports to the test among the Holectypoida, which is the only other gnathostomatous (and therefore rock-dwelling) order. Although the development of the buttresses in the two groups might easily be regarded as an illustration of similar adaptation to similar environment alone, yet, in the light of the other less obviously utilitarian features of the two groups, it seems in this case that a genetic explanation exists as well. On the internal mould of a Pygaster, and yet more in one of a Pileus, besides the deep pits left by the prominences of the SEA-URCHINS. ATT perignathic girdle on the adoral surface, there are grooves (representing ridges in the test) that pass from the processes alongside the ambulacra (but situated on the interambulacra) for a short distance. The structure might be regarded as indicating a gradual rise of the inner surface of the test to form a keel which culminates in the perignathic process. As, among Regular Kchinoids, the perignathic girdle rises quite abruptly from the inner surface, this gradual rise of the test towards the processes shows a new feature, the beginning of the inner buttressing of the test. In Holectypus, as the name implies, a diagnostic feature of the genus as first tentatively suggested by Desor (11) is the absence of grooves in the internal ‘moulds. This of course means the absence of internal ridges passing radially outwards to a point beyond the ambitus. An investigation of some siliceous moulds of H. ? sarthacensis has shown me that, although there is nothing in the interambulacra to compare with the strong ‘“ cloisons” of the succeeding genus, there nevertheless exists a considerable thickening of the adoral regions of those areas, even more than in Pygaster. In Discoidea the first signs of a really efficient internal butitressing appear. Down a line, rather to the adradial side of each half-interradius, there passes a thickening of the test which is rounded near the peristome and becomes carinate further out, and which extends beyond the ambitus. The partitions do not pass for any considerable distance up the adapical surface. The perignathic girdle tends to lean against the adoral’ ends of the supports. In Conulus no such well-marked buttresses appear, but the interambulacral areas undergo a great amount of thickening towards the peristome. Indeed, the perignathic girdle, which is itself well developed, is often less internally elevated than the interambulacral plates against which it reclines. The ambulacra pass in sunken grooves across the adoral surface. In one specimen, on cutting a section through the interambulacrum at a point just outside the perignathie girdle, I found a large hollow to be included between an inner and an outer wall of calcite. I have not been able to verify the occurrence of this feature im other sections. It may, therefore, have been an abnormality or the result of an accident ; but if it should be found to be a general tendency, or even one of fairly frequent occurrence, it would be very significant in the comparisons that might be drawn between it and the double flooring of the test of many of the higher Clypeastroida. It is only in Discoidea that the buttresses are in such a freely projecting condition that they could be expected, by a growth in their height and an accompanying depression of the adapical surface, to form complete vertical partitions in the test. As it is, these “ cloisons” of Discoidea are rather more strongly developed than the corresponding structures of Hchinocyamus, which other- wise they resemble very closely. In fact, Gregory (50), in renaming the “ genus” called Hehinites by Duncan (44), which included only 478 MR. HERBERT L. HAWKINS ON the species Discoidea subucula, used the name Protocyamus “ to indicate the affinity of this Echinoid with the Hchinocyamus series.” The name, on systematic grounds, must be abandoned, but its significance remains. In Conulus, but, so far as I am aware, in that genus only, a definite “sand-canal,” similar to that of Hchinocorys and the Spatangidee, is well developed on the inner surface of the madre- poric genital. In the same genus, in adult specimens, a double row of hemispherical prominences occurs, partly encircling the inner part of the test a little above the ambitus. Klinghardt (68) has recently discussed the relation of these thickenings to the course of the alimentary canal, for the mesenteries of which they seein to have given attachment. He has compared the course of the gut thus indicated with that of several fossil and recent species of Spatangide. In the present state of our knowledge, however, but little of importance can be ascertained of the comparative anatomy of the soft parts of fossil Echinoids. H. The Apical System. Much of the systematic work that has been done on the Irregular Eehinoids has had as its basis the character of the apical system. Notable cases where this feature has been utilized for the purposes of classification are the works of Gaudry (‘ Enchainement du Monde animal’)and Pomel. Froma purely morphological standpoint the system has been carefully described by Lovén (81). In the case of the Holectypoida, and of some of the near allies of that group, I have recently summarized the state of our knowledge of the apical system (Hawkins, 70) in a paper that was definitely a preliminary note to the present work. In consequence, only the comparative aspect of the subject need be dealt with here, and for the description of details that paper may be consulted. The apical system is at first thoroughly disorganized in its composition and structure by the passage of the periproct through its cycle of plates. In Pygaster sens. str., the first stage of dis- ruption is still visible. The posterior genital plate is entirely absent, and the remaining four genitals are grouped in a roughly semicircular order around the anterior edge of the periproct. The madreporic genital is not much larger than the other three. The oculars are small, and show no features of special importance. From a broken and open condition such as that shown by Pygaster sens. str., the processes of evolution work along two definite directions. ‘The first aims at a restoration of a cyclic, or at least of a compact, character in the system as a whole, and the second is concerned with the infilling of the centre of the system (when the cycle is regained) to replace the absent periproct. In the reconstruction of the cycle of genital plates, the posterior (fifth) genital is not necessarily resuscitated. In fact, a very large number of the great groups of the Irregular Echinoids are permanently without this plate. Anorthopygus shows the simplest SEA-URCHINS. 479 condition of the cycle-restoration on this plan. In that genus the postero-lateral genitals close in, so as to bring the system to an F. Cenholectypus. E. Pygaster (Megapygus). H. Clypeaster. (Reduced to a common size, but correct in proportion.) D. Conulus. G. Discoidea (the posterior genital pore not invariable). C. Spatangus. The apical system of some Holectypoids and their allies. B. Anorthopygus A. Pygaster sens. str. approximately circular shape, and the place of the posterior plate is taken by a prolongation of the madreporic genital through the 480 MR. HERBERT L. HAWKINS ON system. This great increase in the size and extent of the right anterior genital achieves two results. Firstly, the terior of the apical system is filled by it (with the madreporite), and secondly, the posterior margin of the system is completed by its extension. The resulting structure is an apical system of the ethmolysian type (see Gregory, 50). The great importance of this character in Anorthopygus becomes evident when it is realized that such a system is found only in it and in a section of the Spatangide. It may be stated at once that the method of infilling of the centre of the system shown in this genus is characteristic of all those Holectypoida in which the apical plates regain a genuinely cyclic arrangement. The second method whereby the system is rendered compact, without the redevelopment of the posterior genital plate, is shown by Conulus. Here the two posterior oculars become greatly increased in size, and meet along the posterior margin of the system. The postero-lateral genitals undergo a similar transverse extension to a greater or less degree, and meet above them. The madreporic genital, although large and partly occupying the centre, is in this way separated from the posterior region of the system. A slight antero-posterior lengthening of the whole system usually accompanies this method of development, and, in a simple sequence indicated in my recent paper, the markedly elongate apical systems of a Pyrina and a Holaster can be readily derived. ‘The Conulus- plan is characteristic of the apical systems of many Jurassic Nucleolitide, although it is not the only type developed in that complex series of forms. Of the type of apical system in which the fifth genital is re- developed (or perhaps replaced by a new but similar plate), Pygaster (Megapygus) shows the first stage. Here one small plate, perhaps more, imperforate and in all probability flexibly united to the others, makes its appearance at the adapical extremity of the periproct. It seems probable that this new genital plate is a specialized member of the anal series which has become in- corporated into the apical system. In Megapygus it is always small and imperforate. The next stage in recovery is seen in Holectypus sens. str. In this genus the fifth genital is present as a recognizable unit of the genital cycle. It is always smaller than its four associates, however; and of these, the madreporic genital is very large, occupying all the central part of the system. The posterior cena is still imperforate. In the succeeding series of forms (Cwnholectypus) the relations of the genital plates are similar to those in the earlier subgenus ; but a genital pore, quite as large as those of the other plates, passes through the posterior genital. Canholectypus shows, then, the perfect re- storation of the apical system. All five genital glands will have been functional, each with a separate pore; while the centre of the apical system is filled by the madreporite, situated, as usual, entirely on the right anterior genital plate. The apical system of Discoidea is particularly interesting. The SEA-URCHINS. 481 fifth genital becomes practically indistinguishable, in point of size, from the others of the cycle, even the right anterior plate being much reduced from its condition in Holectypus. The pos- terior plate may or may not be perforated, this irregularity affording in itself ample proof of the plastic condition (in a variational sense) of the genus. The madreporite, instead of being restricted to the right anterior genital, is more or less uniformly distributed over all five of these plates in some species, a feature never found in the preceding genera. (In the case of an otherwise abnormal Conulus albogalerus, a similar development exists : see Hawkins, 70.) The oculars have dwindled considerably in proportional size. The chief interest of this peculiar structure is seen when a comparison is made between the apical systems of Discoidea and Clypeaster. In the latter genus the madreporite is central and prominent, but it is quite impossible to distinguish the sutures of the genital plates, at least in adult forms. The oculars are minute. Discoidea, then, shows the preliminary stages of the assimilation of the genitals—a phenomenon that is preparatory to their coalescence and fusion in the Clypeastroida, V. Tse INTERNAL EvoLution OF THE ORDER. 1, Features of Phylogenetic Importance. In paleontological attempts to trace a phylogenetic sequence through any series of organisms, the first and essential feature to be considered is the order in time in which the various forms appear. Most of the serious errors that have marred the value of some past work in this direction have resulted from an insufficient reliance on the stratigraphical relations of the genera considered. It is true that our knowledge of the occurrence of fossils at various horizons is very inadequate: it is only necessary to consider the number of cases where a gap exists in the sequence of forms that are known to occur in widely separated horizons, to realize this incompleteness of our knowledge. But it seems a fair postulate to assume that the order in which various genera make their appearance is approximately the true sequence of their evolution. Especially is this the case in the Holectypoida. Not only are they, in common with most Echinoidea, eminently adapted for preservation in suitable deposits, but the periods of their exist- ence, the Jurassic and the Cretaceous, were times when, at least in this country, the conditions of deposition were exceptionally favourable for the preservation of organicremains. In the scheme of evolution put forward below, no apparent relationship has been accepted unless the stratigraphical evidence confirmed it. Asecond great principle from which reliable evidence of genetic affinity can be deduced is that of Ontogeny. Here, unfortunately, our knowledge of the Holectypoida ismeagre. In the Echinoidea generally the process of recapitulation is always very much obscured Proc. Zoo. Soc.—1912, No. XXXI, 3l 489 MR. HERBERT L. HAWKINS ON by the existence of a free-swimming larval stage. Of post-larval changes in the Class but httle is known, Agassiz (80), in the Revision, summarized the state of knowledge of the “young stages of Echini,’ and but little has been added since that date, at least in the case of the Irregularia. Ontogenetic characters are always difficult to observe and to appreciate among fossil forms, and far more zonal collecting of young stages of the Jurassic and Cretaceous Echinoids will be necessary before this line of evidence can be used for their correlation. Some slight details are available at present, such as the Hemi- pedina-phase of Pygaster senisulcatus and the young stages of Conulus with an adapical periproct. (Valette, 69, has described a young specimen of C. swhconicus in which the periproct is already in the adult position, although the individual has a dia- meter of only 10 mm.). Unlike the Mollusca and Brachiopoda, the Echinoidea do not retain the first-formed portions of the test ‘throughout life; so that, although new parts are continually being developed, the acceleration by which these new portions assume adult characters almost nullifies any recapitulatory features they may possess. In the matter of the interambulacral tuberculation, which at first seems a promising structure for ontogenetic study, this feature of acceleration renders the characters of the new plates practically worthless. In addition to their sequence in time, it is therefore necessary to consider the adult characters of each genus separately. The features of an adult are divisible into two kinds. The first group is that of adaptation to circumstances ; and the characters due to this tendency, though interesting from other standpoints, have little phylogenetic meaning. The second group of characters are those which are unaffected, or are not necessarily affected, by the surroundings of the organism, and which must in consequence owe any peculiarities they possess to the line of evolution of the group to which the individual belongs. Such features, which include atavistic and vestigial structures, are of first-rate importance for showing the phylogeny of a group. In the Hchinoidea, the cha- racters that would fall into the first category would be those directly concerned with assimilation, respiration, reproduction, and locomotion. The characters of the second type would consist of apparently trifling variations in the ornament or structure of the test—-variations of such a kind as not to affect the vital processes to any serious degree, nor be affected by them. Such characters are the details of the plating of the ambulacra and the variations, within certain limits, in the structure of the apical system. These two characters are regarded as essential indices of relationship in the present paper. There is, however, in the investigation of an extinct, annectant group like the Holectypoida, an additional principle of evolution that gives safe guidance. The two extremes of structure—those of a Cidarid and of a Spatangid—are known. Generally speaking, the Holectypoida should show a gradual tendency, in the course SEA-URCHINS. 483 of their evolution, to depart from the characters of a Cidarid, and to approximate to those of the Irregular types. A recognition of this direction of evolution in the group renders the interpretation of the various structures more intelligible by including them all in one coherent scheme. S) — Zi 2 ra S rs) ee Seow ECHINOLAMPAS ECHINOC YAMUS NUCLEOLITES ECHINONLUS CLYPEASTER SPATANGUS AMBLY PYCU : 2 a PYGURUS aos Ob. DISCHOLECTYPUS ———— ANORTHO MACROPYGUS iN eae COLNHOLECT YPUS HOLECTYPUS am wu ia, "3 _[IECHINOBRISsU. (Se) 4 0 CLYPEUS Vf bees Be OR GALEROPYCUS PYGASTER ax pe ais a uw Jp} 3 i< DIADEMOID ANCESTOR (#DIADEMOPS!S) Si) Phylogenetic table of the Holectypoida and their allies. Names of Holectypoid genera are connected by thick lines, those of other orders by thin lines. No details are inserted in groups other than the Holectypoida, the names in the external groups being those of the earliest-known genus that has been satisfactorily described. Short, thick, horizontal lines above names indicate that the genera became extinct at that horizon, and left no direct descendants. ambulacral pores of Discoidea with the more elaborate structures of the later genera. Perhaps, if the jJaw-structures of Cono- clypeus were to be discovered in a more perfect condition than 494 MR. HERBERT L. HAWKINS ON those described by de Loriol (35), they also would show an intermediate character. The presence of ‘“ bourrelets” round the peristome in this genus are the only features that seem antagonistic to its being regarded as ancestral to the Clypeuster- series. The similarity between the small species of Discoidea and Echinocyamus caused Gregory (50), when revising the unnecessary generic division of “ Hcehinites” made by Dunean (44), to propose the name Protocyamus. The name is inadmissible on systematic grounds, but would be morphologically appropriate. Hchino- cyamus occurs first in the Upper Cretaceous, and has developed but few changes in structure from that time to the present day. H. L. Clark (64) has recently suggested that the characters of Echinocyamus are not primitive, but rather degenerate. On the stratigraphical evidence I incline to regard them as truly primitive, and to have retained ancestral traits by the retardation of development consequent on their small size. Echinocyamus (of the Fibulariide) was then directly evolved from the smaller (typical) Discoideew, while Conoclypeus (of the Clypeastride) appeared at the same period as a descendant of (probably) the larger species of Discoidea (the “ Pithodia” of Pomel, 37). The former group underwent little change in subsequent periods, but the latter became rapidly differentiated into the numerous and complex types that characterize the other families of the Clypeastroida. VII. Summary. The Holectypoida are restored to the rank of an order of the Echinoidea Irregularia. A classification, somewhat modified from that proposed by Gregory (50), is given, and revised diagnoses of the families, subfamilies, and genera are drawn up. A comparative study of the morphology of the skeletal structures of typical genera of the group is given; and, in the light of the results of this study, the course of evolution both within and beyond the limits of the order is indicated. The Holectypoida are regarded as an annectant group of the Trregular Echinoids, whose characters retain a considerable uniformity owing to a persistent retardation of evolution. At various periods offshoots from the Holectypoid stock appeared, which, usually with a relatively accelerated differentiation, developed into the various orders and families of the Irregularia. The order commenced in the Liassic period, and became extinct at the end of the Cretaceous. Two of the groups of Echinoids now living retain many features that were characteristic of the Holectypoida (the Echinoneide and the Fibulariide), The other groups of Irregular HEchinoids show a much greater departure from the primitive character, but they all possess some features which indicate their Holectypoid ancestry. SEA-URCHINS. 495 Two new names are introduced in the Systematic Part :— Megapygus as a subgenus of Pygaster, corresponding with the Pygaster (sens. sty.) of Pomel (37), with type WM. umbrella; and Conulopsis, a genus including the “ Hchinoconus ” of Desor (21), with type C. roemeri d’Orbigny. The latter group will be studied in greater detail in a forthcoming paper. VILI. List oF LireRATURE CONSULTED. (The numbers of pages and plates in square brackets are those which have a special bearing on the subject. Where no such brackets are present, the whole paper has been consulted.) 1. 1734. J. T. Kuery.—Naturalis dispositio Echinodermatum ete. [p. 24; Pls. xiii—xiv. | 2. 1824. C. Sroxes.—Extracts from a letter explanatory of three drawings of Echini. ‘Trans. Geol. Soc., ser. 11, vol. 11, p. 406. 3. 1829. J. Puitires.—lIllustrations of the Geology of Yorkshire, ete. Part I: [p. 127; Pl. iii. fig. 17.] e 4. 1835. C. DesmouLrns.—Etudes sur les Echinides. II. Généralités. Actes Soc. Linn., Bordeaux, Tome vii, pp. 315-432. 5. 1836. E. Grarerour.—Mémoire de Géo-zoologie sur Jes Oursins fossiles (Echinides) qui se rencontrent dans les Terrains caleaires des environs de Dax. Actes Soc. Linn., Bordeaux, Tome vill, pp. 108-191 ; Pls. i. & ii. [pp. 140-160; PI. i1.} 6. 1837. L. Agass1z.—Prodrome dune Monographie des Radiaires ou Echino- dermes. Mém. Soc. Sci. Nat., Neufchatel, Tome i. (Also in) Ann. Sci. Nat., Tome vii (and in) Annals Nat. Hist., vol i. [p. 302. | 7. 1837. C. Desmoutins.—Etudes sur les Echinides. III. Synonymie générale. Actes Soc. Linn., Bordeaux, Tome ix, pp. 45-364. [pp. 92-105 ; 200-363. | , 8. 1839. L. Acasstz.—Description des Fichinodermes fossiles de la Suisse. Premiere partie, Spatangoides et Clypéastroides. [pp. 61-94; Pls. vi. ; xxii bis. ] 9. 1840. L. Acassrz.—Catalogus systematicus _Ectyporum Echinodermatum fossilium Musei Neocomensis ete. [pp. 3-7. | 10. 1841. L. AGassiz.—Monographies @Echinodermes, vivans et fossiles. Echin- ‘tes. Famille des Clypéastroides. Mon. II. Des Scutelles. 1812. E. Desor.—ld., Mon. III. Des Galérites. 12. 1847. L. Acassiz & EK. Drsor.—Catalogue raisonnée des familles, des genres, et des espéces de la classe des Echinodermes, fase. 2. Ann. Sei. Nat., ser. iii, vol. vii, pp. 129-168. [pp. 143-153. | 13. 1849. E. Forpes.—Mem. Geol. Surv., United Kingdom. Figures and Descriptions of British Organic Remains. Decade I. (Pls. vi & viii. 14. 1850. KF. eT cit., Decade IIT. [ Pls. vi-viii. | 15. 1852. T. Wr1ent.—On the Cassidulidse of the Oolites, with descriptions of some new species of that family. Amn. Mag. Nat. Hist., ser. i1, vol. ix, pp. 81-103 et seqq. _[pp- 88-98; Pls. iii. & iv. | 16. 1854. G. Correau.—Ktudes sur les Echinides fossiles du département de VYonne. Tome I. Terrain jurassique. [pp. 194-220; Pls. xxvii- XXX11. 172: tebbe oe ag Re eel Brit. Foss. Eehinod., Oolitic Formations. Part I. Paleontographical Soe. [pp. 19, 20.) 18. 1856. A. LeEYMERIE & G, CorrEau.—Catalogue des Echinides fossiles des Pyrénées. Bull. Soc. Géol. France, ser. ii, Tome xii, pp. 319-355. [pp. 329- 332. | 19. 1856. J. W. Sarrer.—Mem. Geol. Surv., United Kingdom. Figs. and Desc., Brit. Org. Rem., Decade V._ [ Pls. vii & viil. | 90. 1856. T. Wricur.—Monogr. Brit. Foss. Echinod., Ool. Form., Part II. Paiwontogr. Soc. [pp. 258-290 ; Pls. xvili-xx. | D1. 1857. E. Drsor.—Synopsis des Echinides fossiles. [pp. 161-197; Pls. Xxli- XXxvi.] 496 22. 23. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 1857. 1859. 1859. 1860. 1861. 1889. 1891. 1892. § . P. pE Loriot. MR. HERBERT L. HAWKINS ON E. Prcret.—Traité de Paléontologie. Edit. If, Tome iv. [pp. 223- 229. | G. Corrrau & —. TrigeR.—Hchinides du département de la Sarthe, Seen au point de vue zoologique et stratigraphique. (1855—- 1859. A. p’OrsiaNny [posthumous].-—Paléontologie francaise. Terrains crétaces, ‘ome vi. [pp. 459-550; Pls. 978-1006. | T. Wriagut.—Mon. Brit. Foss. Ech., Ool. Form., Part IV, and Supple- ment. Paleontogr. Soc. [pp. 424-425; 463-464; Pl. xli.] H. Micuetin.—Monographie des Clypéastres fossiles. Mém. Soe. Géol. France, Ser. ii, Tome vii, Mém. 2. _L. Sasmann & A. Dottruss.—Etudes critiques sur les Hchinodermes fossiles du Coral-rag de Trouville (Calvados). Bull. Soc. Géol. France, Ser. ii, Tome xix, pp. 168-184, Pl. 111. . G. Corrzavu.—Paléontologie frangaise. Terr. jurass., Tomeix. [pp. 330 -363 ; 384-503: Pls. 86-91: 98-138. ] . EB. Desor & P. pE Lortot.—Kchinologie Helvétique. Description des Oursins fossiles de la Suisse. Echinides de la période jurassique. (1868-1872). [pp. 257-301; Pls. xliv—xlvi. | . A. Acasstz.—Revision of the Echini, Part IV. Structure and Embry- ology of the Echini. Mem. Mus. Comp. Zool., Harvard, No. vii. S. Lovin.—Etudes sur les Echinoidées. K. Svensk. Vet.-Akad. Handl., Bd. xi, No. vii. _ T. Wrtent.—Mon. Brit. Foss. Ech., Cret. Form., Vol. J. Echinoidea, Part vi. Paleontogr. Soc. [pp, 198-224; Pls. xlvi-li.] Description des Kchinides Tertiaires de la Suisse. (Echinologie Helvétique, Partie iii.) Mém. Soc. Pal. Suisse, Tome ii. [np. 80.] _G. Corrzav, P. A. Paron & V. Gavruter.—Echinides fossiles de VAlgérie. Tome II. Terr. secondaires. Fasc. vi, Htage turonien, pp. 1-110: Pls. i-viil. ‘3 P. pz Lortot.—Monographie des Echinides contenus dans les couches nummulitiques de ’Egypte. Mém. Soc. Phys. Hist. Nat., Genéve, vol. xxvii. [| pp. 75-85. ] _ 8. Loviw.—On Pourtalesia, a genus of Kchinoidea. K. Svensk. Vet.- Akad. Handl., Bd. xix, No. vii. [pp. 20-21; 68~-70.] .Pomen.—Théses doctorales. Thése I. Classification méthodique et genera des Echinides vivants et fossiles. Alger. [pp. 67-76.] conicus Breynius. Geol. Mag., Dee. iii, vol. i, pp. 10-18. -M. Duncan & W.P. Stnapren.—Description of the Fossil Echinoidea from the Khirthar Series of Nummulitic strata in Western Sind. Palxontologia Indica, Ser. xiv: Tertiary and Upper Cretaceous Fossils of Western Sind. Vol. i, part ili, pp. 109-246; Pls. xxi- xxxviii. [pp. 140-149; PI. xxvi-] A _ P.M. Duncan.—On Galerites albogalerus Lamarck, syn. Echinoconus 12 . P.M. Duncan.—On the Perignathic Girdle of the Echinoidea. Journ. Tinn. Soc., Zool., vol. xix, pp. 179-212; Pls. xxx—xxxi. _ P.M. Duncan & W. P. Stapen.—On the Anatomy of the Perignathic Girdle and of other parts of the test of Discoidea cylindrica. Loc. cit., vol. xx, pp. 48-61. _ G. Corrgau.—Paléont. frang., Terr. tert., Tome i, Echinides Kocénes. Tp. 452. | _S. Loviy.—On a recent form of the Echinoconide. Bihang K. Svensk. Vet.-Akad. Handl., Bd. xiii, Afd.iv, No. 10. _ P.M. Duncan.—Revision of the Genera and great Groups of the Echinoidea. Journ. Linn. Soc., Zool., vol. xxii, pp. 1-311. [pp. 25 ; 135-173.] _ P.M. Duncan & W. P. Stapen.—Note on the Perignathic Girdle of Discoidea cylindrica. Ann. Mag. Nat. Hist., ser. vi, vol. iv, pp. 2384-239. ys V. Gaururer.—Description des Echinides fossiles recueillis en 1885 et 1886 dans le région sud les Hauts-Plateaux de la Tunisie par M. Phillipe Thomas. Exploration scientifique de la Tunisie. G. Corrrav.—Paléont. franc., Terr. tert., Tome ii. [pp. 190-898 ; Pls. 249-259. | ‘ Lovin.—Echinologica. Bihang K. Svensk. Vet.-Akad. Handl., Bd. xviil, Afd, iv, No. 1. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. Proc. Zoou. Soc. SEA-URCHINS. 497 1895. G. Corrrau & V. GAurutrr.—Mission scientifique en Perse, par J.de Morgan. ‘ome iii, Partie ii, Paléontologie. Pt. 1, Echinides fossiles. [p. 76; Pl. xii.] 1900. J. W. Grecory.—(in) Lankester’s Treatise on Zoology. Vol. iii, Echinoderma, Chap. xv, Echinoidea. [pp. 315-321: 328.] 1900, E. Hesse.—Die Mikrostructur der fossilen Echinoideenstacheln und derer systematische Bedeutung. N. Jahrb. f. Min., Stuttgart, Beilage-Band xiii, pp. 185-264; Taf. xii & xiii. 1900. J. Lamperr.—Etude sur quelques Echinides de !’Infra-Lias et du Lias. Bull. Soc. Sci. hist. nat., Yonne. Semestre I, Partie 2, pp. 3-57; Pl. i, Tab. A & B. 1900, W. P. SraprEn.—(in) Zittel-Eastman, Text Book of Paleontology, Vol. I. (Echinoidea). [ pp. 233-239. | 1902. C. ScurvETER.—Zur Gattung Caratomus. Zs. D. Geol. Gesell., Bd. 54, pp. 302-335 ; Pls. xi & xii. 1905. F. A. Batrwer.—The Echinoid name Discoidea subucula. Ann. Mag. Nat. Hist., ser. vii, vol. xv, pp. 145-148, 1908. E, 'T. Parts.—Notes on some Echinoids from the Lias of Worcestershire, Gloucestershire, and Somerset. Proc. Cottesw. Nat. F. Cl., vol. xvi, part 2, pp. 143-150. [p. 149.] 1908-9. A. TorNquist.—Die Diadematoiden des wurttembergischen Lias. Zs. D. Geol. Gesell., Bd. 60, pp. 378-384; Pls. xv—xix (1908) ; pp. 385-430 (1909). 1909. A. AGAss1z.—On the existence of Teeth and of a Lantern in the genus Echinoneus Van Phels. Amer. J. Sci., ser. iv, vol. xxviii, pp. 490-492 ; PI. ii. 1909, F. A. Barner.—Triassic Echinoderms of Bakony. Result. Wissensch. Erforsch. des Balatonsees. Bd. I, Teil i, Pal. Anhang. [pp. 108- 113. | 1909. H. L. Hawkrns.—On the Jaw-Apparatus of Discoidea cylindrica (Lamarck). Geol. Mag., Dee. v, vol. vi, pp. 148-152; Pl. vi. 1909. F. Oswatp.—The Degeneration of Armour in Animals. Science Progress, No. xiii, pp. 123-134. 1910. H. L. Hawkrns.—Some Ambulacral Structures in the Holectypoida. Geol. Mag., Dee. v, vol. vii, No. 554, pp. 349-353. 1910. W. LorscuER.—Die westfalischen Galeritenschichten mit besonderer Beriicksichtigung ihrer Seeigelfauna. N. Jahrb. f. Min., Beilage- Band xxx, pp. 269-312. 1911. H. lL. CLarx.—The genera of Recent Clypeastroids. Ann. Mag. Nat. Hist., ser. viii, vol. vii, pp. 593-605. [p. 601. ] 1911. H. L. Hawx1ns.—On the Teeth and Buccal Structures in the genus Conulus Leske. Geol. Mag., Dec. v, vol. viii, pp. 70-74; PI. iii. 1911. H. lL. HawxKrys.—On the Structure and Evolution of the Phyllodes in some fossil Echinoidea. Tom. cit., pp. 257-265; PI. xiii. 1911. H. L. HawxKrys.—On the Tuberculation of the Holectypoida. Tom. cit., pp. 442-454, 1911. Fr. Kurincuarpr.—Ueber die Organisation und Stammesgeschichte einiger Irregularer Seeigel der Oberer Kreide. Jena. Pp. 1-27; Pls. i-xili. ¥ 1911. A. Vanerre.—Description de quelques Echinides nouveaux de la Craie. (Supplement.) Bul. Soc. Sei. hist. nat., Yonne. Semestre IT (1910) pp. 121-151. [pp. 147-149.] 1912. H. L. Hawkrns.—On the Evolution of the Apical System jn the Holectypoida. Geol. Mag., Dec. v, vol. ix. 1912, No. XXXII. 32 498 MR. OLDFIELD THOMAS ON A EXHIBITIONS AND NOTICES. March 19, 1912. . KF. Harmer, Esq., M.A., Sc.D., F.R.S., Vice-President, in the Chair. Mr. A. RapctyrreE Duemore, F.R.G.S., gave a lantern exhi- bition of a large number of photographic studies of wild animals in British East Africa and Newfoundland. This ver y beautiful series of pictures was briefly described by Mr. Dugmore, who dwelt particularly on the advantage to be gained by hunting with the camera, and showed that it was a sport as well as a means of securing interesting and valuable material. Messrs. EK. Gurrarp & Sons sent for exhibition :-— (a) A very fine head of a cow Sable Antelope (Hippotraqus niger), shot by Major EK. C. F. Garraway, C.M.G., which was of interest in that the mane was white instead of the normal dark brown, and in the horns also being near the record for length. (5) The skull of an jlealve line Bear (Ursus isabellinus) with eight well-marked incisors in the lower mandible instead of the normal six. (c) The skull of a Leopard (Felis pardus) with an injury to the nasals and premaxillary bones which had arrested the shedding of the milk-canines and the growth of the permanent canines. The skull was quite adult and the remaining teeth were fully developed and normal. (¢) The skull of a Lion (Felis leo) showing a severe injury or disease of the left side of the palate and the upper mandible, which had not affected the growth of the teeth. Two new Genera and a new Species of Viverrine Carnivora *. My. OuprieLD THomas, F.R.S., F.Z.S., exhibited an example of a Viverrine Carnivore from Tonkin which had a striking external resemblance to the common Hemigalus t hardwickei, but which differed so much in the skull and dentition as to necessitate its being considered a distinct genus. Reason was also given for regarding the Bornean “ Hemigale” hosei as representing a third genus of the group. The following was Mr. Thomas’s account of the animals re- ferred to :— “Commencing with the known species, from Borneo, I propose * |!The complete account of these new genera and the species is given | here, but since the names and preliminary diagnoses were given in the ‘ Abstract, (distinguished by being underlined.__Eprror. | y Better, but erroneously, known as Hemigale. they are NEW VIVERRINE CARNIVORE. 499 to found the following genus for ‘ /emigale’ hosei, which 1 have long realized should be separated from the banded animals forming the true genus /emigalus. “¢ DIPLOGALE, “Thomas, Abstract P. Z. 8. 1912, p. 18 (March 26). * Pattern of coloration normal, not banded. “Skull with pavallel-sided, square-fronted muzzle, the tooth- rows nearly parallel. Septum between anterior palatine foramina without mesial foramen. Meatus and bulla about as in Hemigalus. “Teeth :—Upper incisors forming a straight transverse line, the outer pair scarcely set back behind the level. of the others. Middle teeth (p*, m1?) of the cheek-tooth series proportionally small, terminal ones (p', m°) comparatively large. Pb! as long antero- posteriorly as p*, with two roots and both anterior and posterior supplementary cusps. P* also with marked supplementary cusps, and a postero-internal basal cusp, this being quite absent in Hemigalus. “Type, Diplogale hosei (Hemigale hosei Thos.). Animal and skull described and figured P. Z. 8S. 1892, p. 222, pls. xviii. & xix. “The different shape of the muzzle and palate, the double-rooted p' and other differences in the teeth, and the essential difference in the pattern of coloration are the chief reasons for distinguishing this genus from //emigalus, ** CHROTOGALE. “Thomas, Abstract P. Z. 8S. 1912, p. 17 (March 26). “ Pattern of coloration as in Hemigalus, not as in Diplogale. * Skull—at least in the young—shaped more or Jess as in Eupleres, the muzzle long and slender and the premaxille drawn out forwards, with an abnormally long gap between the last incisor and the canine. Median septal foramen between anterior palatine foramina excessively long, as broad as either of the lateral foramina, and nearly twice their length. Auditory region with the bulle small and narrow, and the meatus very large and open, its diameter approximately equal to that of a cross-section of the bulla itself. ‘Teeth (of a young specimen with the milk-teeth still in place), —Upper incisors quite unique in shape among Carnivora, broad, flattened, spatulate, with a straight cutting- ‘edge, the edges of the six combined forming nearly a_half-circle, owing to the position of i° partly behind the level of i', and of i° again quite behind it—the general outline of the incisive dentition recalling more that of some of the smaller Kangaroos than that of a Carnivore. P! small, single-rooted. Milk-premolars 2, 3, and 4 small and delicate, much smaller than the corresponding teeth of Hemigalus and Diplogale, the proportions more as in Lupleres. Lower incisors again broadened terminally, spatulate, the third with a broader blade than the other two. . 500 MR. OLDFIELD THOMAS ON A *¢ Type -— ‘‘CHROTOGALE OWSToNI. (Text-figs. 61-63.) “Thomas, Abstract P. Z. 8S. 1912, p. 17 (March 26). ‘Colour and other external characters as in Hemigalus hard- wickei, except for the differences indicated in the following description :— “Size apparently about as in H. hardwickei, but the only specimen immature. Fur longer and less sleek than in that animal, the longer hairs of the back, in a half-grown specimen, about 19 mm. in length. Fur of upper side of neck all smoothly directed backwards, like that of the back, instead of being sloped forwards from a whorl on the withers. Text-fig. 61. Chrotogale owstoni. Upper view of skull. The opening in the frontal region is probably of parasitic origin. ‘General colour-pattern in most respects as in A, hardwickei, but the dark dorsal bands are continued rather lower down on the sides of the belly, where also there are a certain number of NEW VIVERRINE CARNIVORE, 501 small irregular dark spots; on the neck the two dark bands are broad and sharply defined, and outside them, on the sides and under surface of the neck, there are similarly a number of blackish spots, such dark markings in this region being quite absent in H. hardwickei. Light ground-colour of upper part lighter than in H. hardwickei, whitish instead of buffy. Under surface pale buffy. Limbs greyish white, the digits scarcely darker. Tail as in H. hardwickei, except that the terminal dark-coloured half is more bushy, the hairs attaining a length of over 30 mm, Text-fig. 62, TERAI~ Chrotogale owstont. A. Palatal aspect of skull. | 3B. Anterior part of muzzle, enlarged. “Skull and teeth as described above, the description being based on a specimen with milk-dentition. Adult dentition un- known. “ Dimensions of the type, measured on the skin:—Head and body (c.) 400 mm. ; tail 260 ; hind foot 70. “Skull: greatest length 91 mm. ; condylo-basal length 85 ; zygo- matic breadth 39:5; nasals 22; interorbital breadth 15; breadth 502 ON A NEW VIVERRINE CARNIVORE. of brain-case 33°7; palatal length 46°5; breadth between outer corners of mp* 21°73; palatal foramina 7-2; median septal foramen 11-6; horizontal length of mi' 2, mi? 3, mi® 3°3, mp? 4-6, mp* 5:4, mp* 3°9. Text-fig. 63. Chrotogale owstoni. A. Side view of skull. | B. Front view of muzzle. “ Hab. Yen-bay, on the Song-koi River, Tonkin. “ Type. Young male. B.M. No. 12.4.21.3. Original number 11. Collected 16 September, 1911, by Mr. Alan Owston’s collector Oru. “This remarkable animal would at first sight be regarded as merely a local representative of the well-known Banded Civet (Hemigalus hardwickei), but a study of its skull and dentition, although only at present represented by a young specimen, shows that it is a most peculiar form, parallel in some respects with the anomalous genus Lupleres, while in others—notably in its almost MR. GUY DOLLMAN ON A SNUB-NOSED MONKEY, 503 kangaroo-like incisors—itis quite unique among Carnivora. And, again, granting its essential distinctness from //emigalus, its really striking external resemblance to that animal is not the least of its many peculiarities, “Tt is to be hoped that adult specimens may soon be obtained, so that we may learn the characters of the permanent dentition. Observations on its habits and food will also be of the greatest interest. ‘“‘T have named the species in honour of Mr. Alan Owston, of Yokohama, to whose enterprise in sending an expedition to Yunnan its discovery is due.” A new Snub-nosed Monkey *. Mr. Guy Dotuman exhibited a new species of Snub-nosed Monkey, allied to Rhinopithecus bieti M.-Kdw., collected at Yen- hay on the Song-koi River, Tonkin. He proposed to call this new form Rhinopithecus avunculus, and described it as follows :— RHINOPITHECUS AVUNCULUS. Dollman, Abstract P.Z.S. 1912, p. 18 (March 26). Size smaller than in Rhinopithecus bieti M.-Edw., with dorsal surface of body black and under parts yellowish buff. Size and general proportions of body much less than in diet? ; tail considerably longer. Hair shorter than in any of the other forms, the general appearance more that of a true Presbytis than a Rhinopithecus. No well-marked crest on crown of head, the hairs in this region only slightly longer than on the neck; in bieti a conspicuous crest is present in both sexes. Ears not con- cealed by dense tufts of hair, rather more marked than in the Mekong species. General colour of dorsal surface deep black, tinged with brownish on the crown and nape; the black color- ation extends all over the dorsal surface, both of body and limbs. Sides of face and forehead creamy-white tinted with buff, the colour gradually darkening on the back of the forehead and merging into the dark blackish brown of the crown. Supra- orbital line of stiff black hairs well developed. Face around eyes naked and apparently flesh-coloured ; a crescent-shaped row of ereamy-white hairs extending from the temporal region on to and across the cheek. Sides of neck orange-buff, the bright buft- coloured hairs forming a most conspicuous border to the dark- coloured nape. Ears with creamy-white tufts arising from their inner sides. Rump with two prominent buffy-white patches on either side of the tail, connecting with the light-coloured markings on the backs of the thighs, but not forming the large conspicuous light-coloured areas such as occur in biet?. Backs of hands and feet covered with rather short black hairs, the hair not sufticiently * |The complete account of this new species appears here, but since the name and a preliminary diagnosis were published in the ‘Abstract’ it is distinguished by being underlined.—Eprror. 504 MR. GUY DOLLMAN ON A SNUB-NOSED MONKEY. long to conceal the digits nor extending over the nails. Entire ventral surface of body yellowish buff, the buff tint most domi- nant on the throat and anterior portion of the belly ; no trace of any grey or dark-coloured hairs on the chest and neck. Inner sides of arms yellowish white, the colour almost white at the elbow and visible from above as a light cream-coloured border, the contrast between the black hairs on the outer side and the bright yellowish white of the inner side of the arm being most marked. The light yellowish colour extends right down the inner sides of the limbs as far as the hands and feet, where it is somewhat duller and dirtier. Tail long, measuring 100 mm. longer than that of bieti ; clothed with comparatively short hairs, except at the tip, where the hairs are rather longer and form a distinct tuft. Colour, above dark black mixed with creamy-white down the mid- line with a creamy-buff border; terminal tuft almost pure white, faintly washed with pale buff; ventral surface considerably lighter. Skull like that of bieti as regards the general shape, but smaller and with smaller cheek-teeth. Supraorbital region rather more like that of rowxellane than of bieti; muzzle formed as in the latter species, without any well-marked concave depression of the premaxillary region. Interorbital breadth less than in rowxellane. Zygomatic arches almost parallel, not expanded laterally. Dimensions of the type (measured in the flesh) :— Head and body 520 mm.; tail 660; hind foot 165; ear 40. Skull: greatest length 109 mm. ; basilar length 68 ; zygomatic breadth 77 ; greatest breadth across orbital region 72°5 ; greatest diameter of orbit 28; interorbital constriction 11; greatest width of cranium 68°3; palatilar length 32:9; width of palate (inside m!) 20:5; length of upper tooth-row, from front of first premolar to back of last molar, 30. . Hab. Yen-bay, Song-koi River, Tonkin. Type. Adult female. Original number 8. Collected by Mr. Alan Owston’s collector, Orii, on September 14, 1911. This interesting Monkey was readily distinguished from its nearest ally, Rhinopithecus bieti, by its dark black back, yellowish- buff underparts, and light-coloured tail. A young specimen, sent with the type, was coloured in much the same manner as the adult, only very much paler, the crown of the head and hind limbs being yellowish tinged with grey, whilst the back was just commencing to become dark. The entire underparts were, as in the adult, a rich yellowish-buff colour. In the course of describing this new Snub-nosed Monkey, Mr. Dollman had been in correspondence with Prof. E. L. Trouessart, of the Paris Museum, concerning the specimens of Rhinopithecus bietti under his charge, and was indebted to Prof, Trouessart for much valuable assistance, most liberally given. Without this assistance the description of this new Rhinopithecus would have been a far more difficult matter. No. 106. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON. March 19th, 1912. S. F. Harmer, Esq., M.A., Sc.D., F.R.S., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed, Messrs. E. GerRARD & Sons sent fer exhibition :— (a) A very fine head of a cow Sable Antelope, shot by Major EK. C. F. Garraway, C.M.G., which was of interest in that the mane was white instead of the normal dark brown, and in the horns also being near the record for length. (6) The skull of an Isabelline Bear with eight well-marked incisors in the lower mandible instead of the normal six. (c) The skull of a Leopard with an injury to the nasals and premaxillary bones which had arrested the shedding of the milk- canines and the growth of the permanent canines. The skull was quite adultand the remaining teeth were fully developed and normal. (Z) The skull of a Lion showing a severe injury or disease of the left side of the palate and the upper mandible, which had not affected the growth of the teeth. Mr. OuprreLD THomas, F.R.S., F.Z.S., exhibited the skin and skull of a Viverrine Carnivore from Tonkin, which, externally, was remarkably like the Banded Civet (Hemigalus hardwickei), but whose skull and teeth proved to be completely different. It was proposed to be called CHROTOGALE OWSTONI, gen. & sp. nn. General coloration as in Hemigalus hardwicket. Skull with long muzzle as in Hupleres. Incisor teeth broad, spatulate, * This Abstract is published by the Society at its offices, Zoological Gardens, Regent's Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in advance, 18 with long level cutting-edges instead of points, their series above forming nearly a half-circle. Cheek-teeth proportionally small. Hab. Tonkin. Type. Young male. Original number 11. Mr. Thomas at the same time proposed to distinguish ‘* Hemi- gale” hoset, described by him in 1892, as a special genus to be called DIPLOGALE, gen. n. segs of coloration normal, not banded. kull with parallel-sided, square-fronted muzzle, the tooth- rows nearly parallel. P* with double root. Type. Diplogale hosei (Hemigale hosei, Thos.). Mr. Guy DouumAn exhibited a Monkey, belonging to the rare genus Lhinopithecus, trom Tonkin, which he considered to represent a new species and proposed to call RUHINOPITHECUS AVUNCULUS, Sp. Nn. Size smaller than in R. bieti, M.-Hdw.; tail longer. Colour of dorsal surface ible. under pai rts yellow ish buff; tail black overlaid with yellowish white, terminal tuft white. Dimensions of type :— Head and body 520 mm.; tail 660; hind foot 165; ear 40. Skull: greatest length 109 mm. Hab. Yen-bay, Tonkin, Type. Adult female, Original number 8. Mr, A. Rapctyrre Duemore, F.R.G.S., gave a lantern exhi- bition of a large number of photographic studies of wild animals in British East Africa and Newfoundland. This very beautiful series of pictures was briefly described by Mr. Dugmore, who dwelt particularly on the advantage to be gained by hunting with the camera, and showed that it was a sport as well as a means of securing interesting and valuable material. Mr. Epwarp W. Suann, B.Sc., read a paper, communicated by Prof.S. J. Hickson, D.Sec., F.R.S., F.Z.8., entitled ‘‘ Observations on some Alcyonaria from Singapore, with a brief Discussion on the Classification of the Famiiy Nephthyide.” This collection was made by Mr. W. F. Lanchester and the late Mr. F. P. Bedford during their residence in Singapore. All the specimens had been obtained in shallow water, from low water-mark to a depth of about 10 fathoms, and of the eleven species dealt with in this paper, representing six different families, four were described as new. A brief historical summary of the genera Vephthya, Dendronephthya, and Stereonephthya was given, together with the author’s reasons for retaining the definitions of these genera 19 of Nephthyide as enunciated by Prof. W. Kiikenthal in his ‘Revision of the Alcyonaria.’ Among the illustrations were reproductions of some of Savigny’s figures of his genera Ammothée and Nephthée. Sir Georcz H. Kenrick, F.Z.S., presented a paper entitled “A List of Moths of the Family Pyralide collected by Felix B. Pratt and Charles B. Pratt in Dutch New Guinea in 1909-10, with Descriptions of new Species.” Mr. T. H. Wrruers, F.G.S., read a paper, communicated by Dr. W. T. Calman, F.Z.S., on “Some early Fossil Cirripedes of the Genus Scalpellum.” ‘Attention was drawn to the form of the carina of the geologically older species of Scalpellum, and it was shown that the earliest forms known resembled more closely the carina of Pollicipes, from which Scalpellum 1s considered to be derived. An almost complete capitulum of the Albian Scalpellum arcuatum was described, together with some scales of the peduncle, and a restoration was given. This specimen was important because, with the exception of a few detached valves found in the Aptian (Lower Greensand), it was the oldest-known fossil Cirripede that could with certainty be referred to the genus Scalpellum, sensu lato. S. arcuatum was considered to be an ancestral form of the group of almost exclusively deep-sea species, which Dr. P. P. C. Hoek had separated as a subgenus under the name Arcoscalpellum, and its relationship to other species was discussed. S. trilineatum was also re-described. The next Mecting of the Society for Scientific Business will be held on Tuesday, April 2nd, 1912, at half-past Hight o'clock P.M., when the following communications will be made :— 1. Exutpirions anp Noricns. ES LE PET LE OTD 2. D. Seru-Surru, F.Z8. Lantern Exhibition of Nestling Cariama, and the display of the Peacock Pheasant. 3. R. I. Pococs, F.R.S., F.L.S., F.Z:8. On a rare Stag (Cervus wallichii) from Nepal, presented to the Society by H.M. The King. (With lantern illustrations.) 20 4, Frank EK. Bepparp, M.A., B.RS., F.Z.S. Contributions to the Aue a Systematic Arrangement of the Cestoidea.—IV. On Species of Znermicapsifer from the Hyrax and on the Genera Zschokkeella, Thysanotenia, and Hyracoteentt. 5. Dr. Basurorp Duran. Additional Notes on the Living Specimens of the Australian Lung-Fish (Ceratodus forsteri) in the Collection of the Zoo- logical Society of London. The following papers have been received :— 1. Junin S. Huxtey. A First Account of the Courtship of the Redshank (Totanus calidris). 2. Mrs. EH. W. Sexton. Amphipoda from Bremerhaven. 3. C. Tare Rucan, M.A., F.ZS. ~ Descriptions of new Ae of the Family Loricariide in the British Museum Collection. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Soctery or Lonpon, Reegent’s Park, Lonpon, N.W, March 26th, 1912. No. 107. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON,* April 2nd, 1912. Dr. A. Smiru Woopwarp, F.R.S., Vice-President, in the Chair. The Minutes of the last Scientific Meeting were confirmed. The Sxcrerary read a Report on the Additions that had been made to the Society’s Menagerie during the months of February and March 1912. Dr. R. W. SxHurevot, C.M.Z.8., sent for exhibition the skins of two young Virginia Opossums (Didelphis virginiana). These specimens were each about ten weeks old and belonged to the same litter. The bones of the entire skeleton at this age were quite elemen- tary in character, especially the terminal vertebre of the tail, the bones of either carpus and those of the tarsi, and the epiphyses of the long bones, ete. ‘he marsupial bones were well formed in both sexes, and upon either side were nearly as long as the corresponding ilium, and about one-fourth the size in bulk. According to Flower, the number of vertebree in the spine of the Virginia Opossum was 7 cervicals, 13 thoracic, 6 lumbar, and 26 caudals. This was probably correct for the adult animal of this species, while in subaduits, of an age here considered, the last three caudals were not developed, and the three or four anterior to them were in the most rudimentary condition possible. * This Abstract is published by the Society at its offices, Zovlogical Gardens, Regent’s Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘Proceedings,’ free of extra charge. to all Fellows who subscribe to the Publications; but it may be obtained on the day ef publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in adyance. 22 In both these specimens the first dentition had perfectly erupted and was as follows :— ; 1 2 3 9 tp €7, PMs, ma= 42, the formula for the adult being 3 4 3, m y= 90. : 1 a Cy, pm 4? The premolars were triangular, sharp-pointed, and flattened from side to side; the molars had numerous sharp cusps, and the canines were large and curved. Mr. D. Sera-Smiru, F.Z.S., Curator of Birds, exhibited, by means of lantern-slides, photographs of the male Peacock Pheasant (Polyplectron chinquis) displaying to the female. The typical display, as depicted in the photographs, resembled very closely that of the Argus Pheasant, the bird facing the female while he lowered the breast to the ground and expanded the wings and tail like a shield, the head being held sideways against one wing. Mr. Seth-Smith also exhibited photographs of the young Cariama cristata hatched and reared in the Gardens in 1911, and remarked that although young of this species had been hatched in the Menagerie on previous occasions, he believed that this was the first occasion on which the young had been reared to maturity. Mr. BR. I. Pococs, F.R.S8., F.L.S., F.Z.8., exhibited a lantern- slide of two Polar Bear cubs born in the Gardens in November 1911, and made some remarks upon the causes of the difficulty experienced in all Zoological Gardens in rearing the offspring of this species. Mr. C. Tare Rucan, M.A., F.Z.8., exhibited some lantern- slides, prepared from photographs taken by Dr. F. B. Sumner, of a Mediterranean Flatfish (Platophrys podas) on sand, gravel, and various artificial backgrounds, showing its power of changing its colour and markings to resemble the gr ‘ound on which it lies. Mr. R. I. Pocock, F.R.S., F.L.8., F.Z.8., Superintendent of the Gardens, read a paper “ On a rare Stag o ( Cervus wallichit) from Nepal, recently presented to the Zoological Society by His Majesty Tone George.” The author pointed out the distinctive pecu- liarities of this species, which, on account of its great scarcity, had never been satisfactorily classified since it was described by G. Cuvier in 1825 froma coloured illustration of a specimen living at that time in the Barrackpoor Menagerie. Some authors had supposed this Stag to be identical with the Kashmir species, or Hangul (Cervus hanglw) ; others had referred it to the Chumbi Valley species, or Shou (Cervus affinis). From both of these, however, it differed in having the rump-patch of large size, ex- tending, that is to say, nearly to the summit of the croup, and 23 showing no trace of a dark median line dividing it into a right and left portion. Nevertheless, with respect to the size of the rump-patch and the distinctness and width of this divisional line, the Shou (C. affinis) seemed to be intermediate between the Hangul (C. hanglu) and Wallich’s Stag (C’. wallichii). In certain other respects, such as the colour of the lips, the length of the head, and the coarseness of the hair, C. afinis and C. wallichii were more like one another than either was like C. hanglu, and the evidence tended to show that the two former were subspecies of a species for which wallichii was the oldest available name. Mr. F. E. Bepparp, M.A., F.R.S., F.L.S., Prosector to the Society, read a paper on species of Tapeworms of the genus Inermicapsifer obtained from the Hyrax, with notes on the genera Zschokkeella and Thysanotenia. An account of the structure and characters of the species was given, together with the description of a new genus and two new species, Dr. Basurorp DeAN contributed an account of the living specimens of the Australian Lung-fish (Ceratodus forstert) in the Society’s Collection. This paper contained some further observa- tions made by the author in June 1911, supplementary to his previous communication published in 1906, and dealt with the coloration, size, and age of the specimens. Details of the rate of growth of this species were also given, with notes on their method of breathing, their food, and an account of the regeneration of a portion of the left ventral fin which had suffered an injury. The next Meeting of the Society for Scientific Business will be held on Tuesday, April 23rd, 1912, at half-past Hight o'clock p.m., when the following communications will be made :— 1. Exurpirions anp Norices. 2. JULIAN S. Huxtey. A First Account of the Courtship of the Redshank (Totanus calidris). 3. Mrs. E. W. Sexton. Amphipoda from Bremerhaven. 24 A. Cx ae Ruean, M. Noy | B.ZS Descriptions of new ches “sf the Family Loricariide in the British Museum Collection. SCS LE CONGR Las IAs “The Circulatory System of ie P Gator Grass-Snake (Zropi- donotus natrix). The following papers have been received :— 1. Major J. Svrvenson Haminton, C.M.Z.S. The Local Races of Burchell’s Zebra. bo . Rownanp HK. Turner, F.Z.S., FES. Studies in the Fossorial Wasps of the Family Scoliide, Sub- families Klidine and Anthoboscine. 3 G. A. Boutmnesr, F.R.S., ye ZS. On z Gites of Fishes aa by Mr. A. Blayney Percival in British East Africa to the East of Lake Baringo. Dpane JB, Ennioien, Wig Wiles “Contr ibutions to ne Ae and Sjstemati Arrangement Devil ieee ursinis), the Type of a new Family. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZooLoGIcAL Society or Lonpon, Regent's Parx, Lonpon, N.W. April 9th, 1912. No. 108. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON.* April 23rd, 1912. Dr. 8S. F. Harmer, F.R.S., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed. The Secretary exhibited a living specimen of a young female Dorsal Hyrax (Dendrohyrax dorsalis) from Nigeria, recently presented to the Society by Mr. J. L. McKellar. The Secretary exhibited a number of photographs of an Elephant Kraal in Siam which had been presented to the Society by the Rt. Hon. Sir Cecil Clementi Smith, P.C., GOM.G: Mr. C. H. O’Donoeuvsz, B.Se., F.Z.S., read a paper on the Circulatory System of the Common Grass-Snake (7Z'ropidonotus natrix). Several interesting features correlated with the loss of limbs and the elongation of the body were stated to occur in the blood-vessels. The vessels, like the viscera they supplied, were asymmetrical ; not only were those on the right anterior to those on the left, but they were also noticeably larger. No indication of the descent of snakes from a limb-bearing ancestry was to be found in the circulatory system, save perhaps a small pair of veins which might correspond to the pelvic veins in Lacertilia. There was a marked tendency for the vessels to form longitudinal systems, ¢. g., the arteries supplying the gut and the fat-bodies ; and each ovarian artery formed a longitudinal trunk along the corresponding supra-renal body. The hepatic portal vein arose by two roots, one from each renal portal vein, and ran the whole length of the gut up to the liver. By the side of each oviduct * This Abstract is published by the Society at its offices, Zoological Gardens, Regent’s Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in advance, 26 was a conspicuous oviducal sinus, a vessel which had not been described previously in snakes. The right carotid artery was not present in the adult, and to compensate for this the left side of the head received its arterial blood by means of three anastomoses—one beneath the medulla oblongata, one beneath the fore-brain, and one beneath the symphysis of the lower jaw. The part of the anterior cardinal vein in the head of the embryo was completely replaced during development by a new vessel, the lateral cephalic vein. Mr. Juuian S. Huxuery read a paper, communicated by Prof. G. C. Bourne, D.Sc., F.R.S., F.Z.S., containing an account of the Courtship of the Redshank (Z'otanus calidris). The first purpose of this paper was to draw attention to the many valuable results to be obtained by simple watching of very common British birds ; and the second was to show how the facts observed in the Redshank bore on the theory of Sexual Selection. Tn this species there was no rival display between several males at once: a single female was courted by a single male, as in Man. The courtship started with a pursuit, the hen running in a circuitous course, followed by the cock. The pursuit was followed by a display, but only if the hen were willing that the courtship should continue. During display the cock uttered a special note, spread his tail, raised his wings above his back, and advanced with a curious high-stepping action towards the now stationary female. Tf the female so wished, pairing followed the display. But in quite 90 per cent. of observed courtships the female rejected the male, either during the pursuit or during the display, by simply flying away, when the cock was quite powerless to enforce his desires. Thus the consent of the hen was absolutely necessary if pairing were to take place, and this consent was usually withheld: in other words, selection by the female was a reality in the Redshank,. Other interesting points were as follows :—The plumage of the two sexes was identical, and was decidedly cryptic when the birds were at rest. During flight the white underside of the wings and the white tail were conspicuously revealed, and probably served as recognition marks. ‘The significance of the red legs ‘was unknown. During display the male drew attention to the underside of the wings by raising and vibrating them, to the tail by fanning it out, and to the red legs by his slow, high steps; besides this he uttered a note heard at no other time. Thus, since the actual colours and structures used in display were found in both sexes, the only peculiarly male possession—the only secondary sexual character of the Redshank—was a special behaviour, devoted to showing off these common colours and structures in a special way. This seemed to show that secondary sexual differences in birds were originally differences of behavionr, and that only when these were established did differences of colour and structure come to be developed. 27 Mrs. E. W. Sexton contributed a paper, communicated by the Rev. T. R. R. Stebbing, M.A., F.R.S., F.Z.S., based on a small collection of brackish- water Amphipoda from Bremerhaven. Special reference was made to a new species of Gammarus, which inhabited both fresh and brackish water, and was interesting as showing in a marked manner the effects of environment on . development, Mr. C. Tare Recan, M.A., F.Z.S., read a paper containing descriptions of ten new species of South American Fishes of the Family Loricariide in the British Museum Collection. The next Meeting of the Society for Scientific Business will be held on Tuesday, May 7th, 1912, at half-past Hight o’clock p.m., when the following communications will be made :— 1. Norices AND EXHIBITIONS, 2. FrANcIS WaRD, M.D., F.Z.8. Lantern and Kinematograph Demonstrations of Photographs of Fishes and Aquatic Animals in Natural Hlumination. 3. G. A. Boutencer, F.R.S., F.Z.8. On a Collection of Fishes made by Mr. A. Blayney Percival in British East Africa to the East of Lake Baringo. 4. Rowianp E. Turner, F.Z.S8., F.H.S. Studies in the Fossorial Wasps of the Family Scoliide, Sub- families Hlidine and Anthoboscine. 5. Ape. CHApmay, F.Z.S. Notes on the Spanish Ibex. The following papers have been received :— 1. Major J. Stevenson Hamitton, C.M.Z.S8. The Local Races of Burchell’s Zebra. 28 2 _ FRANK EK. BrpparD, : M. A., , -R. 8., et Z. 8. ~ Contributions to the ‘Anatomy and Systematic Arrangement of the Cestoidea.—V. On a new Genus from the Tasmanian Devil (Dasyurus ursinus), the Type of a new Family. 3. WuiuuiAM Nicott, D.Sc., F.Z:S. On two new Larval Trematodes from the Striped Snake. 4. W.T. Cauman, D.Se., F.Z.8 On ies a new Ce of the Crustacean Order Branchiura. f, Sg Uno teen, ICG Oe ee ‘A Note on the rare Brush Nadia ror Baas eudactylota Gosse. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. Zoo.tocicat Sociery or Lonpoy, Recent’s Park, Lonpon, N.W. April 30th, 1912. No. 109. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON®* May 7th, 1912. Prof. E. A. Mincuty, F.R.S., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed, Mr. R. I. Pocock, F.R.S., F.L.S8., F.Z.8., Superintendent of the Gardens, exhibited a skin and a living specimen of a fawn variety of the Brown Rat (Hpimys norvegicus), which had been caught on an island in the middle of Loch Corrib, Co. Galway, and presented to the Society by Lord Headley. Mr, Pocock remarked that although similarly coloured varieties of this rat had been caught now and again in different parts of England, it was especially interesting to put on record Lord Headley’s state- ment that it was quite common on the island, no fewer than eleven having been trapped while others had been seen ; and that it did not occur, so far as was known, on the mainland. Typically coloured brown rats lived on the island as. well. Mr. D. Sera-Smirx, Curator of Birds, exhibited two horn-like sheaths which had been shed from the orange-coloured patch at: the base of the lower mandible of the King Penguin (A ptenodytes pennanti) living in the Society’s Gardens. Mr. W. E. de Winton had observed the shedding of this epidermal sheath in a bird living in the Gardens in 1898 (P. Z. 8. 1898, p. 900); but although the present specimen had been carefully watched during two successive moults in March and October 1911 (P. Z.S. 1912, p. 60), no sign of * This Abstract is published by the Society at its offices, Zoological Gardens Regent's Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications ; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings pey annum, payable in advance, 30 this process wasobserved. The bird, however, went through another complete moult in March to April of the present year (1912), and shortly after this was completed the epidermal covering of these orange-coloured patches became loose and finally fell off; the pieces somewhat resembled the wing-cases of a large beetle, being semi-transparent and of a clear orange-colour. Dr. Francis Warp, F.Z.8., showed a number of photographs and diagrams illustrating a method of observation of fishes, birds, and mammals under the water, the principle being that the subjects under consideration were illuminated by natural light, and the observer being ina dark chamber in the water was not seen. The appearance of black-feathered birds was shown; these, by carrying down air-bubbles among the feathers, were converted into reflectors : and a Water-Hen was shown bright red and then green as it reflected the different surroundings in which it had been placed. Otters and Seals were also shown as seen under the water. The demonstration was illustrated by numerous slides and by the cinematograph. Mr. G. A. Boutenerr, F.R.S., F.Z.S., presented a paper on a collection of Fishes made by Mr. A. Blayney Percival in British Kast Africa to the east of Lake Baringo. This collection was of special importance as coming from a district the fishes of which had not been collected before, and contained examples of five new species. Dr. F. E. Bepparp, M.A., F.R.S., F.Z.S., Prosector to the Society, gave an account of his paper on a new Genus of the Cestoidea, founded on some specimens of Tapeworms which he had discovered in the small intestine of an example of the Tasmanian Devil (Dasyurus ursinus). In briefly describing the most salient points of anatomical interest in this form, which formed the type of a new Family, he remarked that in view of the very considerable peculiarities of structure observed it was remarkable that the generative organs did not show any marked features of interest as compared with those of other Tapeworms. Mr. R. E. Turner, F.Z.8., F.E.S., communicated a memoir entitled ‘‘Studies in the Fossorial Wasps of the Family Scoliide, Subfamilies Elidine and Anthoboscine.” Several new species of Elidine from South Africa were described, including a new genus in which the female was wingless, and the genus Anthobosca was monographed. The geographical distribution of Anthobosca, which was almost entirely confined to the Southern Hemisphere, was discussed, and the conclusion was reached that the distribution was due to survival from a wider range in the past, and not to a southern origin. 31 - Mr. Apex Cnapman, F.Z.S., contributed a short paper containing some notes on the Spanish Ibex, with reference to Prof. Angel Cabrera’s recent paper on this species, The next Meeting of the Society for Scientific Business will be held on Tuesday, May 21st, 1912, at half-past Hight o'clock p.M., when the following Comiiunications will be made :— 1. A. Buayney Perctvat, F.Z.S. Lantern Exhibition of Game Animals from British East Africa. 2. Major J. Stevenson Hamiuton, C.M.ZS. The Local Races of Burchell’s Zebra. 3. WiuuiAM Nicotu, D.Sc., F.Z.S. On two new Larval Trematodes from the Striped Snake. 4. W.'T. Cautman, D.Sc., F.Z.8. On Dipteropeltis, a new Genus of the Crustacean Order Branchiura. 5. G. A. Bouencer, F.R.S., F.Z.8. Second Contribution to our Knowledge of the Varieties of the Wall-Lizard (Lacerta muralis). 6. Sir Cuartes Extor, K.C.M.G., C.B., F.Z.S. ————— an A Note on the rare British Nudibranch Hancockia eudactylota Gosse, The following papers have been received :— 1. R. Lypexser, F.R.S., F.Z.8. The North Rhodesian Giraffe. 2. Prof. 8. J. Hickson, F.R.S., F.Z.S. On the Hydrocoralline Genus Hrrina. 32 - 3. FRANK E . Bepparp, |] M.A., D Se., aE RS qlee Ss. Contributions to the renee ree Sy eoiatie Arrangement of the Cestoidea.—VI. On an Asexual Tapeworm from the Rodent Fiber xzibethicus, showing a new form of Asexual Propagation, and on the supposed ‘Sexual form. 4. HELEN lie INL, LEibeaiiin, BSe., EZ Poly cheeta from Pacific a North America.—Part I. Ser pulidee, with a Revised Table of Classification of the Genus Spirorbis. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Society oF Lonpon, ReEGENtT’s Park, Lonpon, N.W. May Ath, 1912. Wo. 110, e wt ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON.* May 21st, 1912. Sir Epmunp G. Loprr, Bt., Vice-President, in the Chair, The Minutes of the last Scientific Meeting were confirmed. _ The Secretary read a report on the Additions that had been made to the Society’s Menagerie during the month of April 1912. Mr. A. Buayney Percivan, F.Z.8., exhibited a number of photographs and lantern-slides of Game Animals from British East Africa, including a fine series of the Reticulated Giraffe. Mr. D. Sera-Smiru, F.Z.S., Curator of Birds, exhibited two living specimens of a rare Lory, Calliptilus solitarius, from Fiji, and remarked that Dr. Philip H. Bahr had recently brought home two specimens which had died. The specimens exhibited were from a collection of eight brought home alive by Mr. Rood Tarte, of Taviuni Island, one of the Fijian group, where this very beautiful species was still abundant, its numbers having been very considerably reduced in the other islands by the introduced mongoose. The exhibitor referred to a recent note on the species by Dr. Babr in ‘ The Ibis’ for April 1912, p. 293. Major J. Stevenson Hamiuron, O.M.Z.S., the Game Warden of the Transvaal, communicated a short paper, illustrated by photo- graphs, on the local races of Burchell’s Zebra, and pointed out that it was possible to shoot in one herd individuals presenting the characters of various subspecies as described by systematists. In the Transvaal, for example, he obtained skins exhibiting features claimed to be distinctive of such races as LZ. burchelli wahlbergi, E.b. transvaalensis, and £. b. chapmanni ; and from his experience * This Abstract is published by the Society at its offices, Zoological Gardens, Regent’s Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications; but it may be obtained on the day of publication at the price of Siapence, or, if desired, sent post-free for the sum of Sia Shillings per annum, payable in advance, 34 he expressed the opinion that these subspecies had been based upon inadequate museum material. Dr. WitiiAM Nico, F.Z.8., communicated some observations on two new Trematode larve found encysted in enormous numbers in the mesentery of several Striped Snakes ( 7ropidonotus ordinatus sirtalis) which had died in the Society’s Gardens. He named these forms, as neither could be referred to any adult species already known. It could be safely predicted, however, that the second species completed its life-cycle in the intestine of a bird, and from this fact it could be inferred that the Striped Snake was eaten by birds. Dr. W.T. Catan, F.Z.S., read a short paper describing a new genus and species of the Cructacean Order Branchiura. A parasite of fishes collected by Spencer Moore, Esq., at Corumba, Matto Grosso, Southern Brazil, was referred to a new genus as follows :— DIPTEROPELTIS, gen. n. Differing from Argulws in having no spine on the preoral papilla ; in having the antennules and antenne very minute and imperfectly segmented ; in having no large spines or hooks on the under surface of the carapace, body, or appendages ; in having no furcal rami on the abdomen ; and in having the lateral wings of the carapace greatly elongated. Genotype, D. hirundo, sp. n., with the characters of the genus. Mr. G. A. Boutencer, F.R.S., F.Z.8., read a paper entitled “Second Contribution to our Knowledge of the Varieties of the Wall-Lizard.” This paper was a continuation of one published in the Society’s ‘ Transactions ’ in 1905, and dealt chiefly with the variations of Lacerta muralis in South-Eastern Europe and South- . Western Asia. It also contained a supplement to the first part, thus completing an account of the varieties, of which about thirty were regarded as more or less definable, the author endeavouring to show the inconstancy of the characters adduced by some her- petologists in assigning specific rank to a number of these forms, connected by many gradations. Mr. Boulenger hoped to support his statements by a number of photographic figures of specimens selected out of the enormous material which had passed through his hands in the course of his study of this polymorphic and widely distributed lizard. This paper will be published in the ‘Transactions’ in due course. A short note on the rare British Nudibranch Hancockia eudactylota Gosse was received from Sir Charles Eliot, K.C.M.G., 35 C.B., F.Z.S., with some coloured figures of a single specimen captured at Plymouth. These were of special interest, as no coloured figure of this species had yet been published. The next Meeting of the Society for Scientific Business (closing the Session 1911-1912) will be held on Tuesday, June 4th, 1912, at half-past Eight o’clock p.m., when the following communications will be made :— 1. E. G. B. MeapEe-Watpo, V.P.Z.S. will introduce a discussion on the Preservation of the English Fauna. 2. R. Lypex«er, F.R.S., F.Z.S. The North Rhodesian Giraffe. 3. Prof. 8. J. Hickson, F.R.S., F.Z.S. On the Hydrocoralline Genus Zrrina. 4, Frank KE. Bepparp, M.A., D.Sce., F.R.S., F.Z.S8. Contributions to the Anatomy and Systematic Arrangement of the Cestoidea—VI. On an Asexual Tapeworm from the Rodent Fiber zibethicus, showing a new form of Asexual Propagation, and on the supposed Sexual form. 5. Heten L. M. Prxett, B.Sc., F.Z.S8. Polycheta from the Pacific Coastof North America.—Part I. Serpulide, with a Revised Table of Classification of the Genus Spirorbis. 6. R. Broom, D.Sc., C.M.ZS. On some new Fossil Reptiles from the Permian and Triassic Beds of South Africa. The following papers have been received :— 1. E. Duxr1nFretp Jonss, F.Z.S., F.E.S. Descriptions of new Butterflies of the Genus Thecla from 8.E. Brazil. 36 2 ee Bsns VAG BSc. On the Development of the Pectoral Girdle in the Pipe-fish (Syngnathus acus). 3. F. F. Larpraw, F.Z:S. Some Notes on Bornean Dragonflies, with Descriptions of New Species. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Society or Lonpon, ReEcENtT’s Park, Lonpon, N.W. May 28th, 1912. Nor dE. ABSTRACT OF THE PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF LONDON.* June 4th, 1912. E. G. B. Meapr-Watpo, Esq., Vice-President, in the Chair. The Minutes of the last Scientific Meeting were confirmed. Mr. E. G. Bourencer, Curator of Reptiles, exhibited a clay- pall containing a cocoon of the African Lung-fish (Protopterus annectens) presented to the Society by Capt. J. A.M. Vipan, F.Z:8. He briefly alluded to the habits of the fish and the formation of the cocoon, and gave an account of the method to be employed in order to release the fish, The Preservation of the Native Fauna of Great Britain. Mr. E. G. B. Meapre-Wapo, Vice-President of the Society, ntroduced a discussion on the Preservation of our Native Fauna, in which Mr. A. Heneage Cocks, Dr. F. G. Dawtrey Drewitt, and Mr. Stewart Blakeney (who sent a written contribution) joined. ‘Lhe necessity of creating public opinion on the matter was urged. It was agreed that the laws with regard to birds were sufficient, if administered strictly. With regard to mammals, it was the opinion of those present that the use of steel traps, instead of snares, for catching rabbits was chiefly responsible for the ex- termination of wild cats, martens, and polecats in many parts of the country, and ought to be suppressed. Mr. R. Lypexkxer, F.R.S., F.Z.S., communicated a short paper describing a new local race of Giraffe from the Petauke district of North-east Rhodesia. * This Abstract is published by the Society at its offices, Zoological Gardens, Regent’s Park, N.W., on the Tuesday following the date of Meeting to which it refers. It will be issued, along with the ‘ Proceedings,’ free of extra charge, to all Fellows who subscribe to the Publications ; but it may be obtained on the day of publication at the price of Sixpence, or, if desired, sent post-free for the sum of Six Shillings per annum, payable in advance. 38 Miss Heten L. M. Prxett, B.Sc., F.Z.S., read a memoir entitled “ Polycheta from the Pacific Coast of North America. Part I.” This paper contained a description of Serpulide from the Straits of Georgia, chiefly the Departure Bay region of Vancouver Island, together with some specimens from Victoria and Puget Sound, eighteen species inall, of which five werenew. Serpula splendens (Bush, 1905) was shown to be identical with Serpula columbiana (Johnson, 1901); and Caullery and Mesnil’s classification of the genus Spirorbis was revised and enlarged to contain three new species and such other Pacific species as had been adequately described. Further evidence was given in support of the sug- gestion made by Caullery & Mesnilin 1897 that Spirorbis (Circeis) armoricana (St. Joseph, 1894) was only a variety of Spirorbis spirillum (Linné, 1760). Mr. R. 1. Pocock, F.R.S8., F.Z.S., Curator of Mammals, read a paper, illustrated by lantern-slides, on antler growth in the Cervide with special reference to Hlaphurus and Dorcelaphus, and pointed out that the growth of the individual antler in Elaphurus, as shown by a series of sketches kindly supplied by Lord Tavistock, proved that the anterior and posterior branches of the antler of Hlaphurus were homologous with the brow-tine and beam of the Sambar’s antler, and that in Dorcelaphus the sub- basal snag was the homologue of the brow-tine in the Old World deer as Sir Victor Brooke claimed. Dr. Hans Gapow, F.R.S., F.Z.8., read a paper on ‘The One- sided Reduction of Ovaries and Oviducts in the Amniota, with remarks on Mammalian Evolution.” He stated that the reduction began with the oviduct, and a first cause of the invariably right-sided bias had to be looked for in the turning of the embryo upon its left side, a position which influenced the growth and relative position of the stomach and primary intestinal loops, these being stowed in the abdomen in such a way that they were less disturbed by an egg passing through the left than through the right oviduct. In the Monotremes also only the left ovary and duct were functional, although those of the right side were structurally not affected. This was not a case of reptilian inheritance. Proto- Meta- and Eutheria represented a continuous, monophyletic line of evolution, with the Monotremes and Marsupials as offshoots. The Metatherian stage was diphy- odont, marsupiate and placental. It was the parting of the ways. Those which developed a corpus callosum, correlated with higher mental faculties by further improving the placentation, and losing the marsupium (not the bursz), became Placentalia; whilst the remaining stock, being driven to arboreal life, intensified the marsupial and thereby diminished the uterine gestation. Their arborealism implied the necessity of taking their young with them. 39 When Eutheria took to arboreal life the chance of reviving the lost marsupium was gone, nor did their higher mental and placental organization require it. Dr. F. E. Bepparp, M.A., F.R.S., F.Z.S8., gave an account of an asexual Tapeworm, obtained from the Musquash (Fiber zibethicus), showing a new form of asexual propagation, and also described a sexual worm which he believed to be the mature form of the same Tapeworm, Dr. Wiuur1AM Nico, F.Z.8., described two new Trematode parasites from the Indian Cobra (Naja tripudians). The first was found in the gall-bladder and was made the type of a new genus of the family Dicrocoeliide. The second was found in the ureters and represented a new species of the genus Styphlodora. Dr. Nicoll also gave statistics of the Worm Parasites collected from the animals which had died in the Society’s Gardens during the period from December 1910 till April 1912. Dr. R. Broom, C.M.Z.8., presented a paper based on some new Fossil Reptiles from the Permian and Triassic Beds of South Africa. Prof. 8. J. Hickson, F.R.S., F.Z.S., communicated a paper on the Hydrocoralline genus Hrrina. This genus was founded by Gray in 1835, and since that date two other genera (Labiopora and Spinipora) closely related to Hrrina had been described. An analysis of the characters of these three genera was given. An examination of Gray’s type of Errina proved that it was more closely related to the species referred by Moseley and others to the genus Labiopora, than to the species referred by them to the genus Hrrina. The author proposed, therefore, to merge the three genera into one with the common generic name L7rrina, dividing the species into three subgeneric groups. Two new species were described, one from New Zealand waters and the other from the Cape of Good Hope. 40 This Meeting closes the Session 1911-1912. The next Meeting of the Society for Scientific Business will be held on Tuesday, October 29th, 1912, at half-past Hight o’clock p.m. The following papers have been received :— 1. E. DuxinrieLp Jonss, F.Z.8., F.E.S. Descriptions of new Butterflies of the Genus Thecla from S.E. Brazil. 2. F. F, Larpuaw, F.Z.S. Some Notes on Bornean Dragonflies, with Descriptions of New Species. Communications intended for the Scientific Meetings should be addressed to P. CHALMERS MITCHELL, Secretary. ZOOLOGICAL Society or Lonpon, Recent’s Park, Lonpon, N.W. June 11th, 1912. Papers (continued). Pie Page 20. On the Pairing of Pseudoscorpiones. By H. Waxuts Kew, F.Z:S. (Text-figs. 47-50.) 376 21. A Contribution towards the Knowledge of the Spiders and other Arachnids of Switzerland. By the Rev. O. Prckarp-Camsripeas, M.A., F.RS., C.M.ZS. (ext-fies: 51h 52.) es eee ose Bish CON TREN CT BOE DEI a Sarde S ck wode 398 22. On the Blood-parasites found in Animals in the Zeological Gardens during the four years 1908-1911. By H. G. Puruer, F.R.S., F.Z.S., Pres.R.M.S., Pathologist to GEL tC Ee Stee IE TAN Yat alc sbecehn'e a9 aja: ease a +0 pace, « don talsnn deat as ate eas 406 23. On the Structure of the Internal Ear and the Relations of the Basicranial Nerves in Dicynodon, and on the Homology of the Mammalian Auditory Ossicles. By R. Broom, MP sey OOM Z Sir. (bis aV Land Text-fig, 53.) 0 co. ee as oe aleleleveime a ale tune state 419 24. Zoological Results of the Third Tanganyika Expedition, conducted by Dr. W. A. Cunnineron, 1904-1905. Report on some larval and young stages.of Prawns from Lake Tanganyika, By Prof. G. O. Sars, C.M.Z.S. (Pls. LVIL-LX.)............. 426 25. The Classification, Morphology, and Evolution of the Echinoidea Holectypoida. By Hersret L. Hawgriys, MSc, F.G.S8.; Lecturer in Geology, University College, ume ( MieC BIO, B—-GU.) cv ie aye av sess « cnoy « viisde. # 60 0, 6 #inié do ve vin la view nithe a) Selle a eA Titlepage i List of Council and Officers ii List of Contents........ ili Alphabetical List of Contributors ix New Generic Terms ........... xvi SMPTE ERM eA eS CLC IROL ETT ONL IELEN I *solvivr ee. cose artlaverepeheta +6, 0 Wid mye, uals oie» oslcahe alan som ale AT ee Pade tea xvii Tndex of Bisaeeuisone Bd oor LIST OF PLATES. 1912, Part IL. (pp. 241-504). Plate Page XXXII) XXXIV. XXXV. XXXVI. | KXRWII! | XXXVIIL. DOOD | XL. Peper a veg Gd gate ok ARN ln eyelet hel | XLVIII. Mimetic Cockroaches and Beetle Models ............... 858 XLIX.y L. | LL. | : HeLa SPOOR ATABLLESE 50 wolaye thee ermal a lllerainer aN eh ae reeY a eek te eee LI. LIV. | Ly. : LVI. The Auditory Regiom in Dicynodon ........0.......++2. 419 LVII. \ ee Cee from: ake. Tanganyika +/7).\s0) Jens ose vase aoe ao LX. ) f NOTICE. The ‘ Proceedings’ for the year‘are issued in fowr parts, paged consecutively, so that the complete reference is now P. Z. 8. 1912, p.... The Distribution is as follows :— Part I. issued in Mareh. asi Ned ls 3 June. » LIL. 4, September: Cad BN - December. ‘ Proceedings,’ 1912, Part I. (pp. 1-240), were published on March 13th, 1912. ‘The Abstracts of the Proceedings,’ Nos.106 to 111 are contained in this Part. 43) ct ot Sea PRD, ih yi i i i ) / f ) \\ f ‘ Yu bib ety rit VP ae | wh a ar ih, a 5 Roll One ran ye 7 t I I ¢ i yd ui) HAN es 391 0847 2 3 9088 0 Reese a uatebet ato Latino cape reiate ae th Bow Teg y ‘