i 5 4 MOSTLY MAMMALS 



is of the concentric type (as shown in fig. A), in which 

 the central ridges are longitudinal and the external ones 

 form broad ellipses. In the chimpanzee, however, and 

 probably also in some or all of the other manlike apes, the 

 pattern on the balls of the fingers is of the form known as 

 the looped type, which is of common occurrence in the 

 fingers of the human hand. On the finger-tips of man 

 alone occurs the still more complicated whorled type ; and it 

 is thus evident that even in such a minute detail as the 

 arrangement of the lines on the fingers the manlike apes 

 and man stand apart from their kindred, and that in man 

 alone is the most complicated type ever developed, although 

 even in him it is comparatively rare. 



