ON THE EXTINCT MAMMALS OF AUSTRALIA. 223 



Report on the extinct Mammals of Australia, loith Descriptions of cer- 

 tain Fossils indicative of the former Existence in that Continent of 

 large Marsupial Representatives of the Order Pachydermata. 

 By Prof. Owen, F.R.S. 



The fossil bones discovered by Major (now Colonel Sir T. L.) Mitchell, in 

 the ossiferous caves of Wellington Valley, and described in the Appendix to 

 his ' Expeditions into the Interior of Australia,' established the former exist- 

 ence in that continent, during the period apparently corresponding with that 

 of the deposition of our post-pliocene unstratified drift, of species of Wombat 

 (Phascolomi/s), Potoroo (ITi/psiprt/mnus), Phalanger (Phalangista), Kanga- 

 roo (Macroptts), and Dasyure (Dasi/urus) ; but not any of the remains were 

 referrible to the known existing species of those genei'a, whilst some of the 

 extinct species, as the Macropus Titan and Macropus Atlas, greatly exceeded 

 in size the largest known Kangaroos*. The fossil Dasyure (Das. laniarms) 

 also far surpassed in bulk any of the known Dasyures now living in Australia, 

 and more than equalled the largest existing species (Dasgurus ursinus), 

 which is confined to Van Diemen's Land. The fossil lower jaw, which, from 

 the width of the dental interspaces, I was led to doubt, in 1838, whether to 

 refer to the Dasyurus laniarius or to " some extinct marsupial carnivore of 

 an allied but distinct speciesf," I have subsequently been able to identify, 

 generically, with the Thylacinus, by comparison with the skull of that species, 

 — the Hyaena of the Tasmanian colonists, — which I have lately received through 

 the kindness of Sir John Franklin :{:. In addition to the fossils thus generically 

 allied to the peculiar marsupial Mammalia of the Australian continent and 

 adjacent islands, I likewise detected in one specimen § an indication of a 

 species surpassing in size any of the others, and with characters so peculiar 

 as to justify me in regarding it as generically distinct from all known recent 

 or fossil Mammalia, and for which I proposed the name Diprotodon \\ , subse- 

 quently referring it to the same marsupial family as the Wombat^. 



Since the period of the examination of the fossils above alluded to, Sir 

 Thomas Mitchell has at different times transmitted other mammalian fossils 

 to Dr. Buckland and myself, from the plains of Darling Downs ; the College 

 of Surgeons has received from Dr. Hobson, of Melbourne, South Australia, 

 remains of large extinct Mammalia discovered by Mr. Mayne in recent ter- 

 tiary or post-pliocene deposits of the district of Melbourne ; and I have been 

 favoured by Count Strzelecki with the opportunity of examining the collec- 

 tion of fossils obtained by that enterprising and accomplished traveller whilst 

 exploring the cave district of Wellington Valley in 1842. 



In the notices of some of these fossils which I have communicated to the 

 ' Annals of Natural History,' the former existence of a large Mastodontoid 

 quadruped was first indicated** by a fossil femur; the gigantic Proboscidian 

 being subsequently determined, by a molar tooth obtained by Count Strze- 

 lecki from a bone-cave in the interior of Australia, to have been very nearly 

 allied to the Mastodon angustidetis-\-\ . 



* Mitchell's ' Three Expeditions into the Interior of Australia,' 8vo, 1838, vol.ii. p. 359. 



t lb. p. 363. 



X Entire and well-preserved bodies of the Thylacine have since been transmitted by 

 Ronald Gunn, Esq. to the Royal College of Surgeons. 



§ Mitchell, toe. cit., pi. 31, figs. 1 and 2. 



II lb. p. 362. The name has reference to the two large incisive tusks in the lower jaw, a 

 type of dentition common to several existing marsaipial genera, but displayed on a compara- 

 tively gigantic scale by the extinct quadruped in question. 



H ' Phascolomyidae,' Classification of Marsupialia, Zoological Transactions, vol. ii. p. 332. 



** Annals of Natm-al History, vol. xiii., May 1843, p. 329. ft lb., vol. xiv. p. 268. 



