ADAPTATION 



243 



Signal Marks. Signal marks include the white tails of deer 

 and rabbits, which are shown only when the animal runs or when 

 the tail is raised. 



Recognition Marks. The red lateral spots of trout have been 

 interpreted as recognition marks, since they are visible to fishes 



^ 



B 



Fig. 147. — Catocala ilia Cramer. A, on the bark of a tree with wings folded; 

 B, the same moth with wings spread. The hind wings are orange with 

 black bands. 



at their own level, while above and below trout have the char- 

 acteristic dark and light protective colors so common in fishes. 

 The colors of moths and Ijutterflies have been added to this 

 category, but there is abundant evidence pointing toward the 

 sense of smell as the chief means of recognition among such insects. 

 Confusing Colors. Colors of this nature are undoubtedly 

 effective. The Catocala moths and many grasshoppers have 



