238 



GREGORY: NOTHARCTUS, AN AMERICAN EOCENE PRIMATE 



Fig. 83. Comparative series: manus of Notharchis, Lrnnrr and higher primates. Lower four figures natural size. 



1. Nothardus osborni. Amer. Mus. No. 11474. Middle Eocene (Lower Bridger). The oldest and most primitive known primate 

 manus, with narrow carpus, short metacarpals and long digits. Adapted mainly for grasping the branches of trees and for leaping from 

 branch to branch. 



2. Lemur mongoz. Amer. Mus. No. 22886. Manus differing from that of Nothardus chiefly in the lengthening of the metacarpals 

 and flattening of the digits. Hallux widely divergent, digit IV the longest. 



3. Cebus hi/poleiicus. Amer. Mus. No. 14016. Manus adapted partly as a true hand, partly for running along the branches of 

 trees. Digits 2, 3, 4 subequal in length. 



4. Macacus nemestriyius . Amer. Mus. No, 14012. Manus a true hand, with very mobile thumb. Adapted also for running on the 

 ground. Carpus wide. 



5. Gorilla sp. Amer. Mus. Nat. Hist. Manus of modified brachiating type, in which the hands are used partly as hooks in 

 climbing. Thumb somewhat degenerate. Giantism reflected in the great size and robust character of the hand. 



6. Homo sapiens. This particular hand is very short and wide, but evidently represents a modification of a primitive brachiating 



type. 



