776 PROF. BALDWIN SPENCER ON A [Nov. 20, 



The following papers were read : — 



1. A Description of Wynyardia bassiana, a Fossil Marsupial 

 from the Tertiary Beds of Table Cape, Tasmania. By 

 Baldwin Spencer, M.A., F.R.S., C.M.Z.S., Professor 

 of Biology in the University of Melbourne, Director of 

 the National Museum, Melbourne. 



[Received July 9, 1900.] 



(Plates XLIX. & L.) 



For many years the Tasmanian Museum in Hobart has been in 

 possession of a block of calcareous sandstone, obtained from the 

 " Turritella-zone " in the Tertiary beds of Table Cape, containing, 

 partly exposed to view, the remains of a marsupial, which in life 

 must evidently have been of the size of a large Phalanger, though 

 of stouter and more massive build than any existing one. 



I have to express my cordial thanks to the Council of the 

 Museum and to the Curator, Mr. Morton, for the opportunity of 

 examining the specimen, the especial interest of which lies in the 

 fact that it is the oldest marsupial yet found in Australia, as 

 the Turritella-zone is regarded, from palseontological evidence, as 

 belonging to the Eocene deposits l . 



Whilst a large number of fossil mammals from Australia have 

 been dealt with by Owen, McCoy, de Vis, Stirling and Zietz, 

 Broome, and others, none of an age earlier than Pleistocene have 

 been hitherto discovered, the specimen now described being the 

 solitary one as yet found in Australia which dates back as far 

 as the Tertiary period. Pleistocene fossils reveal the existence of 

 highly specialized forms such as Thylacoleo and Diprotodon, asso- 

 ciated with representatives of living genera ; whilst the Eocene form 

 appears to be in no way highly specialized, but unites within itself 

 structural features which serve to ally it, on the one hand, with 

 the most generalized of the Diprotodontia — the Pbalangerida?, and 

 on the other hand with the most typical Polyprotociontia — the 

 Dasyuridoe. This is exactly what we might expect to find, on the 

 supposition that the present Diprotodont marsupials of Australia 

 have been developed in the Australian region from earlier Polypro- 

 todont forms, and that the more highly specialized Diprotodonts 

 were comparatively late developments. 



The earliest and, in fact, the only reference to the fossil occurs in 

 Johnston's ' Geology of Tasmania/ where it is briefly described as 

 " the almost perfect skeleton of a species of Halmaturus obtained 



. l G. B. Pritchard, "A Revision of the Fossil Fauna of the Table Cape Beds, 

 Tasmania," Proc. R. S. Vict. 1895, p. 74. Professor Tate, however, has 

 recently referred the beds, doubtfully, to the Oligocene : Trans. R. S. South 

 Austr. vol. xxiii. pt. i. p. 107. 



