Tertiary.-] PALAEONTOLOGY OF VICTORIA. {Mammalia. 



fossil Wombat which may be the Phascolomys pliocenus (McCoy), 

 the characters of the mandible or lower jaw of which I have 

 previously described (Decade 1, plates 3, 4, and 5,) from our gold 

 drifts and other Pliocene Tertiary deposits. It has a few peculiar 

 characters, in some respects intermediate between the common 

 living P. platyrhinus (Ow.) of Victoria and the P. latifrons (Ow.) 

 = P. McCoyi (Gray) of South Australia, and totally different 

 from the species living in Tasmania, although in the same deposits 

 the Tasmanian Devil (Sarcophilus ur sinus) is common a species 

 still living in Tasmania but not now living in Victoria or elsewhere 

 on the mainland. 



In the Tasmanian Wombat, Phascolomys Wombatus, the sacrum 

 is composed of seven vertebrae anchylosed by the centrums, the 

 four anterior sacral vertebrae have the ends of the diapophyses 

 expanded and anchylosed together, and these four articulate with 

 the ilia in old, but only the anterior two in young individuals ; the 

 three posterior vertebrae have their diapophyses directed outward 

 and backward and are also dilated at their ends and anchylosed 

 together (in some cases the diapophyses of the first caudal are 

 directed forwards and articulate with the sacral). 



In the South Australian hairy -nosed Wombat, Phascolomys 

 (Lasiorhinus) latifrons, there are four anchylosed sacral vertebrae, 

 the hinder half of the diapophyses of the first and the whole of 

 those of the second articulating with the ilia (in one of the skeletons 

 before me of this species there are only three of the sacral vertebrae 

 with confluent diapophyses, another equally adult having four as in 

 Professor Owen's example) ; the distal halves of the expanded 

 diapophyses of the first and second vertebrae are confluent and a 

 less proportion of the third and fourth ; the distal end of the last 

 extended forward. The three following caudal vertebrae have 

 broad depressed diapophyses directed backwards, and free at their 

 ends. 



In P. platyrhinus Prof. Owen notes a difference in the only two 

 skeletons known to him ; a large full-grown one having four sacral 

 vertebrae with the ends of their diapophyses coalescing ; the 

 articulation with the ilium being by the whole width of the first 

 and second ; the diapophyses of the fifth vertebra, or first caudal, 



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