Equally in keeping with mammals' lack of gay colors and minutely elab- 

 orate patterns is the fact that the great majority of them are nocturnal, hiding 

 by day in hollow trees and holes in the ground. Nevertheless, in addition to 

 a complete general adequacy, based, for the most part, on full and perfect 

 counter shading, mammalian concealing-costume presents many beautiful 

 types of generalized obliterative picture-pattern. Some of these are the sub- 

 jects of our next two chapters. 



