THE NEOTROPICAL REGION 



79 



Sub-region present but few features of interest ; they are, 

 with one exception, all of genera found also in the Guiano- 

 Brazilian Sub-region. 



As might have been expected from the dearth of forests 

 and the generally severe climate, the American monkeys 

 and marmosets are entirely unrepresented in the Patagonian 

 Sub-region. On the other hand, at least two small species 

 of Opossum {Didelphys and Dromiciops) occur in Chili, 

 and a very remarkable form of Armadillo (Ghlamy- 

 dophorus) is peculiar to Argentina and the high plateau 

 of Bolivia. 



The following list of the mammal genera of the Pata- 

 gonian Sub-region is constructed on the same plan as that 

 of the preceding tables : — 



Section VIII. — The Past History of the 

 Neotropical Mammal-fauna 



During the last few years our knowledge of the extinct 

 mammals of the Neotropical Region has been enormously 

 increased by the discoveries of the palaeontologists of the 

 Argentine Republic, more particularly by the labours of 



