102 



MR. R. I. POCCCK ON THE EXTERNAL 



Im Ahuatta and Lagothrix the hand is relatively larger and its 

 -cligits are longer as compared with the foot than in the genera 

 previously mentioned, and the space in the hand between digits 

 2 and 3 is markedly greater than between digits 1 (pollex) and 2 

 or 3 and 4. The hands are thus in a sense zygodactylous, like 



Text-figure 7. 



C 



A. Right hand of Alouatta villosa, young, 



B. Kiglit foot of the same. 



C. Extremity of tail of Ateles ater. 



the paws of Phascolatxtos and of Cuscics amongst the Marsupials, 

 tliere being a grasping interval between digits 2 and 3 instead of 

 between digits 1 and 2 as in Lemurs and Catarhine Monkeys *. 



* From a photograph of a living Fitheeia pitJiecia I judge that there is a wide 

 space between digits 2 and 3 in tliat genus also. 



