498 APPENDIX E 



seeks to escape observation, or succeeds in escaping observation that is, 

 when it crouches motionless, or skulks slowly, with the conscious aim of not 

 being seen. No color scheme whatever is of much avail to animals when 

 they move unless the movement is very slow and cautious; rats, mice, 

 gophers, rabbits, shrews, and the enormous majority of mammals which are 

 colored in this fashion are not helped by their special coloration pattern at 

 all when they are in motion. Against birds of prey they are practically 

 never helped by the counter-shading, but merely by the general coloration 

 and by absence of movement. Their chief destroyers among mammals 

 such as weasels, for instance hunt them almost or altogether purely by 

 scent, and though the final pounce is usually guided by sight, it is made 

 from a distance so small that, as far as we can tell by observation, the 

 "counter-shading" is useless as a protection. In fact, while the general 

 shading of these small mammals' coats may very probably protect them 

 from certain foes, it is as yet an open question as to just how far they 

 are helped (and indeed in very many cases whether they really are helped 

 to any appreciable extent) by what Mr. Thayer lays such especial stress 

 upon as being "full obliterative shading (counter-shading) of surface 

 coloring." 



Certainly many of the markings of mammals, just as is the case with 

 birds, must be wholly independent of any benefit they give to their pos- 

 sessors in the way of concealment. Mr. Thayer's pictures in some cases 

 portray such entirely exceptional situations or surroundings that they 

 are misleading as, for instance, in his pictures of the peacock and the 

 male wood-duck. An instant's reflection is sufficient to show that if the 

 gaudily colored males of these two birds are really protectively colored, 

 then the females are not, and vice versa; for the males and females in- 

 habit similar places, and if the elaborate arrangement of sky or water 

 and foliage in which Mr. Thayer has placed his peacock and wood-drake 

 represented (which they do not) their habitual environment, a peahen 

 and wood-duck could not be regarded as protectively colored at all; 

 whereas of course in reality, as every one knows, they are far more difficult 

 to see than the corresponding males. Again, he shows a chipmunk among 

 twigs and leaves, to make it evident that the white and black markings 

 conceal it; but a weasel which lacks these markings would be even 

 more difficult to see. The simple truth is that in most woodland, moun- 

 tain and prairie surroundings, any small mammal that remains motionless 

 is, unless very vividly colored, exceedingly apt to escape notice. I do 



