DERMATOGLYPHICS IN PRIMATES 



151 



membral difference, New World monkeys present unlike 

 zonations in palm and sole, but the differences are small. The 

 contrasts between hand and foot in gibbon, in great apes and 

 in man are marked, and among them the intermembral differ- 

 ences vary in regional distribution. Habits of prehension and 

 locomotion, including brachiation, distinguish these forms 

 from Old World monkeys, in which we have pointed out like- 

 ness of hand and foot. The factors accountable for the differ- 

 ing intermembral conditions in gibbon, great apes and man 



* Double entries indicate variable numbers available for the determinations 



of the several regions- 



** The data for I. II, III, and IV are based on 1244 individuals-, 

 for H d and H p . 20O ; and for Th^.50. 



must remain for the present unknown, though it is likely that 

 there is at least a partial functional explanation for the dif- 

 ferences, on the same principle which is suggested as the 

 source of their distinction collectively from Old World 

 monkeys. 



It is not intended to suggest that the explanation of the 

 differences between hand and foot in regional asymmetries 

 is concerned only with functional influences. That other factors 

 are introduced is evidenced, for example, by the similarity of 



