277 



but it differed externall}' in its larger size and in being of a smooth dark 

 chocolate-colour on all its upper parts, and, as regards the skull, in having 

 a longer facial portion in comparison to the cranium. — P. L. S dater, 

 Secretary. 



3. Linnean Society of New South Wales. 



April 29th, 1896. — (1) Theoretical Explanations of the Distribution 

 of Southern Faunas. By Captain F. W. Hutton, F.R.S., Hon. Member. 

 After reviewing the various theories which have been offered to explain the 

 difficult and intricate problem of the distribution of southern faunas, the 

 author points out that the supposition that the ancestors of certain groups 

 migrated from the northern into the southern hemisphere by the present 

 continents, and have since then become extinct in the north, explains a good 

 deal, but fails to give a full and satisfactory explanation of the whole of 

 the facts. Moreover the members of the fauna unaccounted for are old forms 

 and consequently the means of communication which served them must long 

 ago have been destroyed. To the authour a fatal objection to the theory of 

 migration by way of an Antarctic Continent is offered by the following con- 

 sideration. Aplacental Mammals — both Multituberculata and Polyproto- 

 dontia — existed in Europe and N. America in the Triassic and Jurassic 

 periods, and these Polyprotodontia were, no doubt, the ancestors of the 

 living Polyprotodontia of Australia. In the Eocene strata of Patagonia re- 

 mains of a large number of Polyprotodontia have been found which are far 

 more closely related to the Polyprotodontia of Australia than to the Meso- 

 soic forms of Europe and N. America ; consequently a direct land communi- 

 cation must have existed between these two southern countries. Now there 

 is strong geological and palaeontological evidence that no land ridge existed 

 between N. and S. America during the Mesozoic and early Cainozoic eras; 

 consequently we must assume that the southern forms migrated through the 

 Malay Archipelago ; and, if they went to Patagonia by means of an Ant- 

 arctic continent, they must have passed throug Australia. But mingled with 

 the Eocene Marsupials of Patagonia there are a number of Eutheria of typi- 

 cally South American character — Edentata, Toxodontia, Typotheria^ Peris- 

 sodactrjla, Rodentia, and even Platyrrhine monkeys — without any northern 

 forms of Artiodacti/la, Carnivora, or Insectivora\ and it is hardly possible that 

 these should have passed through Australia without leaving any record be- 

 hind. The theory of the former existence of a South Pacific Mesozoic Con- 

 tinent, first suggested by Huxley, seems to be the only theory left. It not 

 only explains the origin of the Australian and S. American marsupials, but 

 also the almost simultaneous appearance of different Eutherian mammals in 

 North and South America. We must suppose thas this continent threw off 

 first New Zealand, then Australia, then Chili, and finally disappeared under 

 the waves. At a later date. New Zealand must have formed part of a large 

 island joined to New Caledonia, but not to Australia. The objections to 

 this theory are geological rather than biological, involving the doctrine of 

 the persistence of continental and oceanic areas upon which geologists are 

 not agreed; and such objections are equally applicable to the theory of an Ant- 

 arctic Continent. — 2) Report on a Bone Breccia Deposit near the Wombeyan 

 Caves, New South Wales : with Descriptions of some new Species of Mar- 

 supials. By R. Broom, M.D., B.Sc. A detailed examination of this de- 



