717 



MARSUPIATA. 



MARSUPIATA. 



718 



H. penicittatui. 

 H. Gaimardi. 

 H. campestris. 

 Phascolomys Wombat. 

 P. latifrons. 

 Phascolarctos cinemts. 

 Phalangista vulpina. 

 P. Cookii. 

 P. concinna. 

 Petaurus Australia. 



ifacropus unguifer, 

 if. antilopinus. 

 if. agilis. 

 if. brachiotis. 

 if. inornatut. 



Echidna aculeata. 



ifacropus giganteus. 



M. (giganteus) ocydromus. 



if. luiiatus. 



M. Isabellinus. 



M. fatciatus. 



if. hirtttus. 



M. cont/>icillalM (Barrow Island). 



if. Irma. 



if. Derbianus. 



M. brachyuru* (King George's 



Sound). 

 if. laterals, 

 jfypsiprymnut Grayi. 

 H. peniciilatui. 



H. Gilbertii (King George's Sound). 

 H. platyops. 

 Phalangista vulpina. 

 P. v. xantltopiu. 

 P. Cookii. 

 P. concinna. 



Perameles obesula. 

 P. fasciata. 

 Chceropus castanotis. 

 Myrmecobius fasciatus. 

 Phascogale penicillata. 

 P. Jlavipes. 

 P. albipes. 

 P. crassicaudata. 

 Dasyurus Geoffroyi. 



North Australia. 



Afacropus concinnus. 

 Phalangista wulpina. 

 Petaurus breviceps, var. Ariel. 

 Perameles macroura. 

 Dasyurus hattucatui. 



Western Australia. 



Phalangusta, Neillii (King George's 

 Sound). 



Tarsipes rostratus (Swan River and 

 King George's Sound). 



Perameles (Macrotii) lagotis (Swan 

 River and King George's Sound). 



P. Bougainvillii (Peron's Penin- 

 sula, Shark's Bay). 



P. obesula. 



P. myoriwos (Swan River and 

 King George's Sound). 



Chasropus cattanotis (Swan River). 



Myrmecobius fasciatus (Swan River 

 and King George's Sound). 



Phascogale penicillata. 



P. calura. 



P. apicalis. 



P. leucogaster, var. Jlavipes (?). 



P. albipet (?). 



P. crassicaudata. 



Dasyurus Geoffroyi. 



Van Diemen's Land. 



Ornithorhynchus paradoxui. 

 Echidna (aculeata) tetoia. 

 ifacropus giganteui. 

 if. rujicotlis, var. Sennettii. 

 M. JBillardierii. 

 Jfypsiprymnus cuniculus. 

 II. murinut. 

 Phatcolomys Wombat. 

 Phalanyiita vulpina. 

 P. Cookii. 

 P. nana. 



Peramelet obesula. 

 P. Gunnii. 



Phascogale Swaituonii. 



P. minima. 



P. leucopus. 



Dasyunis maculatus. 



D. civerrinus. 



D. ursinut. 



Thylacinui cynocephalus (Bass's 



Strait). 

 Echidna. 



Macroput rtif.coUis( King's Island). 

 Photcolomyt Wombat. 

 Dasyurus maculatus. 



Ornithorhynchut parodoxut. 



Echidna aculeata. 



ifacropus giganteui. 



M. frcenatus (interior). 



if. leporoidei. 



it. robustut (interior). 



M. r/w. 



M. Parryi. 



if. Ualabatut. 



M. Thetidit. 



if. Purma. 



H. dorsal it (interior). 



if. peniciilatui. 



Hypriprymntu rufetccnt. 



II. penicillatus. 



II. Gaimardi. 



H. murinut. 



Phatcolomys Wombat. 



New South Wales. 



Phatcolarctui cinercus. 



Phalangista vulpina. 



P. canina (interior). 



P. Cookii. 



Petaurus taguanoides. 



P. Australia. 



P. fdureus. 



P. breviceps. 



P. (acrobata) pygmieus. 



Perameles obesula. 



P. naiuta. 



P. fasciata. 



Phascogale penicillata. 



P. Jlavipes. 



P. marina. 



P. macroura. 



Dasyurus Geoffroyi. 



D. viverrinut. 



Fulfil Atartupiata. 



Besides the Fossil Opossum (Didelphys Cuvieri) of the Montmartre 

 Oypsum, figured and described by Cuvier in the 'Annales du Museum,' 

 and in his ' Ossemens Fossiles,' and the fossil Dasyurus, Ifypsiprimnus, 

 Halmaturus, Phancolomyi, and Kangaroo, described by Mr. Clift and 

 Cuvier and Mr. Pentland, from the Australian bone-caverns and bone 

 breccia, there are some fossil forma now generally considered as belong- 

 ing to the Martwpiata, which it will be necessary, on account of the 

 great interest which attaches to them both geologically and zoologically, 

 to mention more at length. We commence with those fossil jaws origi- 

 nally described as belonging to the Manupiata which were found at 

 StonwfiekL 



Uuntkerimn, Owen (Amphitherium, De Blainville; Didelphys, 



Cuvier). In consequence of strong doubts having been expressed by 

 M. De Blainville, from inspection of casts, respecting the mammife- 

 rous nature of the fossil jaws found at Stonesfield, and assigned to the 

 Marsupiata by Baron Cuvier, a paper ' On the Jaws of the Thylaco- 

 therium Prevostii from Stonesfield ' was read before the Geological 

 Society by Professor Owen, giving a detailed account of the fossils from 

 a careful inspection of the originals. In this communication Professor 

 Owen confined his description to the jaws discovered at Stonesfield, 

 characterised by having 11 molars in each ramus of the lower jaw. 

 He commenced by observing that the scientific world possesses ample 

 experience of the truth and tact with which Cuvier formed his judg- 

 ments of the affinities of an extinct animal from the inspection of a 

 fossil fragment ; and that it was only when so distinguished a com- 

 parative anatomist as M. De Blainville questioned the determinations, 

 that it became the duty of those who possessed the means to investigate 

 the nature of the doubts, and reassure the confidence of geologists in 

 their great guide. 



When Cuvier first hastily examined at Oxford, in 1818, one of the 

 jaws described in Professor Owen's paper, and in the possession of 

 Dr. Buckland, he decided that it was allied to the Didelphys (" me 

 semblerent de quelque Didelphe "*) ; and when doubts were raised by 

 M. Constant Prevost, in 1 824)1- relative to the age of the Stonesfleld 

 slate, Cuvier, from an examination of a drawing made for the express 

 purpose, was confirmed in his former determination ; 'but he added 

 that the jaw differs from that of all known carnivorous Mammalia, in 

 having 10 molars in a series in the lower jaw. ("II [the drawing] me 

 confirme dans 1'idee que la premiere inspection m'en avoit donnde. 

 C'est celle d'un petit carnassier dont les machelieres resemblaut beau- 

 coup a celles des sarigues ; mais il y a dix de ces dents en sdrie, nombre 

 que ne moutre aucun carnassier connu." ' Oss. Foss.,' v. 349, note.) 

 It is to be regretted that the particular data, with the exception of 

 the number of the teeth, on which Cuvier based his opinion, were not 

 detailed ; but he must have been well aware that the grounds of his 

 belief would be obvious, on an inspection of the fossil, to every com- 

 petent anatomist : it is also to be regretted that he did not assign to 

 the fossil a generic name, and thereby prevent much of the reasoning 

 founded on the supposition that he considered it as belonging to a 

 true Didelphys. 



Professor Owen then proceeded to describe the structure of the 

 jaw ; and he stated that having had in his possession two specimens 

 of the Thylacotherium Prevostii belonging to Dr. Buckland, he had no 

 hesitation in declaring that their condition is such as to enable any 

 anatomist conversant with the established generalisations in com- 

 parative osteology, to pronounce therefrom not only the class but the 

 more restricted group of animals to which they have belonged. The 

 specimens plainly reveal, first, a convex articular condyle ; secondly, a 

 well-defined impression of what was once a broad, thin, high, and 

 slightly recurved triangular coronoid process, rising immediately 

 anterior to the condyle, having its basis extended over the whole of 

 the interspace between the condyle and the commencement of the 

 molar series, and having a vertical diameter equal to that of the hori- 

 zontal ramus of the jaw itself : this impression also exhibits traces of 

 the ridge leading forwards from the condyle and the depression above 

 it, which characterises the coronoid process of the zoophagous marsu- 

 pials ; thirdly, the angle of the jaw is continued to the same extent 

 below the condyle as the coronoid process reaches above it, and its 

 apex is continued backwards in the form of a process; fourthly, the 

 parts above described form one continuous portion with the horizontal 

 ramus of the jaw, neither the articular condyle nor the coronoid being 

 distinct pieces, as in reptiles. These are the characters, Professor 

 Owen believes, on which Cuvier formed his opinion of the nature of 

 the fossil ; and they have arrested the attention of M. Valenciennes in 

 his endeavours to dissipate the doubts of M. De Blainville.J 



From the examination of a cast, M. De Blaiuville however has been 

 induced to infer that there is no trace of a convex condyle, but in 

 place thereof an articular fissure, somewhat as in the jaws of fishes ; 

 that the teeth, instead of being imbedded in sockets, have their fangs 

 confluent with, or anchylosed to, the substance of the jaws, and that 

 the jaw itself presents evident traces of the composite structure. 



In answer to the first of these positions, Professor Owen stated that 

 the portion of the true condyle which remains in both the specimens 

 of Thylacotherium examined by Cuvier and M. Valenciennes, clearly 

 shows that the condyle was convex, and not concave. It is situated a 

 little above the level of the grinding surface of the teeth, and projects 

 beyond the vertical line dropped from the extremity of the coronoid 

 process, but not to the same extent as in the true Didelphys. In the 

 specimen examined by M. Valenciennes, the condyle corresponds in 

 position with that of the jaw of the Dasyurus rather than the Didel- 

 phys ; it is convex, as in mamrniferous animals, and not concave as in 

 oviparous. The entire convex condyle exists in the specimen belong- 

 ing to the other genus, Phascolotherium, now in the British Museum. 

 Professor Owen is of opinion that the entering angle or notch, either 

 above or below the true articular condyle, has been mistaken for 

 " une sorte d'dchancrure articulaire, un peu comme dans les poissons." 



* * Ossemens FOBS.,' torn, v., p. 349. 



* ' Annales (les Sciences Nat.,' Avril, 1825 ; also the papers of Mr. Brodcrip 

 and Dr. FittoD, in the 'Zoological Journal,' 1828, vol. ill., p. 408. 



* ' Comtes Kendiu,' 1838, Second Semestre, No. 11, Sept. 10, p. 527, et eeq. 



