No. 536] ADAPTATIONS OF THE PRIMATES 



491 



and lower Pliocene spread over a large part of Europe 

 (France, Germany, Switzerland). However when the 

 colder climate of the Pliocene developed, the European 

 contingent was exterminated, and only those in Asia 

 have survived as the gibbons of to-day. 



The second group which developed especially strength 

 is rare both in prehistoric and recent times : but it seems 



to have originated first in southern Europe though no 

 representatives have yet been found. In the Pliocene 

 however the genus Siwia has been found in southern 

 Asia where its representatives still remain as the orang 

 utan. During the Pleistocene representatives of the 

 group seem to have reached Africa where they have per- 

 sisted as the gorilla. 



The third group has at its base Dryopithecus, the 

 middle and upper Miocene ape which ranged over a con- 



