8 



THE SENSE OF TOUCH IN ANIMALS 



Tlie meaning of the patterns of ridges found on them is a different 

 question. Certain other regions, such as the phalangeal joints, 

 show pads in some animals which Miss Whipple calls secondary. 

 Only two other terms require notice, the thenar and hypothenar 



Fig. 2. — Diagram of Topography of Pes. (Aza)a''s Opossvm.) 



regions of the hand, corresponding to the eminences at the bases 

 of the first and fifth digits of the hand. 



It is very interesting to note the value of this grouping of the 

 apical and interdigital pads. The latter do not lie in the same 

 axis as the former, by which arrangement a large surface between 

 the digits would be left without a specially tactile area, but they 

 lie just in those intervals between the digits which ensure that the 



