BY R. M. JOHNSTON, F.L.S. 183 



of this group have been found in the later cave breccias 

 and other deposits of Australia deemed to be of Post- 

 Phocene age. 



Marsupial remains have not yet been detected in 

 Australia in deposits older than the Tertiary period. 

 Mammalian remains of Mesozoic age, — such as Micro- 

 lestes, Amphitherium , Amphiiestes, Phascolotherium, Ste- 

 reognatkus, Plagiaulax^\ Spalacotherium^, Galestes*, and 

 Peratherium of Europe ; and Allodon, Ctenacodon, Dryo- 

 lestes, .Sli/laoodon, Asthenodon, Laodon, Diplocynodon. 

 Docodon, Enneodon, 31enacodon, Tinodon, Triconodoyi^ , 

 JBracidus, and Paurodon of the Jurassic age, in North 

 America, — have heretofore been referred to the Mar- 

 supialia on the authority of Professor Owen and other 

 eminent specialists : the dentition of certain of them 

 approaching closely to the existing Hypsiprymnus of 

 Australia ; of some to the existing Opossums ; and of 

 others to the existing Myrmecohkis of Western Australia. 



The remains in the earlier Tertiary formations of Aus- 

 tralia are generally very imperfect. From the teeth and 

 other bones preserved, however, Professor Owen and other 

 authorities have recognised the following genera — viz., 

 Bettongia, Hypsiprymnus, Hahnaturus, Nototherium, 

 Phalangista, Sarcophilus . and Phascolomys. With the 

 exception of the giant extinct vegetable-feeder, Notoilie- 

 rium, all the genera here referred to have living repre- 

 sentatives either in Australia or Tasmania. 



Of the genera marked with an asterisk. Professor 

 Alleyne Nicholson states'' : " Fourteen species are known 

 from the Middle Purbeck beds of England {Oolitic), all 

 of which are probably referable to the Marsupialia, and 

 all of which, except PJagiaidax, are Polyprodont." The 

 largest of these are deemed to be no bigger than a polecat 

 or hedgehog. Plagiaulax is by various authorities believed 

 to be most nearly allied to the existing kangaroo-rats 

 of Australia and Tasmania {Hypsiprymnus). Professor 

 Owen, hovt^ever, regards it as more allied to the carnivorous 

 group. The genera Spalacotherium, TriconodMn, and 

 Galestes have been referred to as insectivorous, having 

 their nearest allies in our Australian phalangers and in 

 the American opossums, 



a Manual of Palaeontology, 1879, vol. ii., p. 293. 



