FEET AND HANDS 



Connected with this carriage of the body are differences 

 in the proportions of the limbs, the existence of a heel, 

 and the loss of the ape-like great toe, which serves in 

 them the functions of a thumb. A man in fact is short 

 armed, firmly plantigrade, with a pronounced heel, and 

 with no " thumb " on his feet. Besides, there are minor 

 differences which we may properly insist upon as dis- 

 tinctive of man. Not, however, all the commonly 

 supposed differences. For example, man is not a hairless 

 mammal at all. It is true that the hairy covering is not 

 obvious everywhere, as it is in apes ; but an investiga- 

 tion with the microscope will show that the hair follicles 

 exist in reality where the hairs themselves are so fine 

 as to escape, or almost to escape, detection. It is quite 

 possible, moreover, that the wearing of clothes, which 

 is doubtless an exceedingly ancient habit of man, is 

 responsible for the not great development of hair. 

 The smooth and unridged skull is a human attribute, 

 and so. is the proportionately larger size of the brain 

 than in the Anthropoid apes. It must be remembered, 

 however, that in the smaller monkeys the brain is some- 

 times proportionately large. 



The S-like curvature of the spine is a human char- 

 acteristic in so far as it is more perfectly developed in 

 man than in apes ; and there are, in short, a number of 

 other small characters which are merely differences of 

 degree and not of kind from the corresponding struc- 

 tures in the monkeys. 



This group, Primates, which must therefore include 

 man, is easy enough to distinguish from groups lying 

 lower in the series if we extend it so as to include the 

 lemurs. 



The group is an eminently arboreal one ; in fact, the 

 exceptions to this are but few. Co-related with this 

 general mode of life are the opposable thumb and great 

 toe, a character which is almost universal in the order, 



20 



