﻿EXTINCT OPOSSUMS. 27 I 



Brazil and South Africa, and nowhere else. Then, again, the 

 remarkable Anomodont reptiles {Dicy?iodo/i, (S:c.) of South 

 Africa are closely connected with those of India ; while the 

 respective alliances between the extinct Labyrinthodont Am- 

 phibians and the Secondary floras of South Africa, India, and 

 Australia are too well known to need more than mention. 



It appears, then, that, altogether apart from the extinct 

 Marsupials, the common factors connecting the faunas and 

 floras of the four great southern prolongations of the con- 

 tinental land of the globe undoubtedly point, not only to a more 

 or less intimate connection between those several areas, but 

 also to their more or less partial isolation from the more 

 northern lands. 



FAMILY DIDELPHYID^ {supra, p. 193). 

 GENUS DIDELPHYS {suprci, p. 196). 



The number of species of Opossums which have been 

 recorded in a fossil state is so large that it would be weari- 

 some to detail them here, more especially as the teeth and 

 jaws of all the members of the family are very similar in 

 structure, and consequently difficult to distinguish from one 

 another in a fossil state. It will consequently suffice to 

 notice some of the chief formations in which remains of the 

 genus occur. 



In the first place, remains of a large number of species of 

 Opossums are found in the Pleistocene deposits of the caverns 

 of Minas Geraes, Lagoa Santa, inland from Rio de Janeiro, 

 Brazil. The greater number of these remains appear inse- 

 parable from species still inhabiting the same country ; and 

 they have been referred to species ranging in size from D. Mar- 

 siipialis to the minute D. pusilla. 



In the Tertiaries of Argentina teeth and jaws of Opossums 

 have been discovered which are assigned to extinct species 



