j 8 6 J Thayer on Protective Coloration. 3*9 



though they only passed for details of the ground beyond the 



egg- 

 It was to' this latter experiment that I alluded in a footnote 

 (1. c., p. 127), when I said that brilliant top colors scarcely tend to 

 interfere with the gradation's power. This statement does not 

 apply, however, to creatures in which, as in a Blue Jay, the 

 bright color so predominates as to form a silhouette shaped like 

 the creature, but only when the bright pattern goes, as it were, its 

 own way, not accompanying the animal's form. 



Yet, even in the Jay's case, his gradation down to white 

 under throat and belly diminishes so greatly his conspicuousness 

 in the dim forest shade, that he may be suspected of great 

 indebtedness to this arrangement of color as he skulks among the 

 leaves. He must often be much helped, also, by the fact that 

 whenever his gradation works its charm and denies his substan- 

 tiality, his blue is likely, at least, to appear to belong to whatever 

 surface, far or near, forms his background for the beholder's eye 

 at the moment ; as for instance a bit of blue distance seen 

 through the leaves. And often when he is not concealed to this 

 degree, his ghostly appearance still tends to cause the beholder 

 to think him further off than he is, which may be sometimes 

 equivalent to concealment. The reader should compare a graded 

 blue egg with one blue all over, both seen in deep woods. Let 

 me urge the reader to understand these color-phenomena, which 

 are the open door into a new world of most charming study of 

 special cases of protective coloration hitherto misunderstood. 



One must remember that by far the greater part of the objects 

 he espies as he walks are first caught sight of out of the side of his 

 eye; and it is this faint seeing against which all this faint appearing 

 is so potent, in countless cases where the animal could not elude 

 the direct eye. In my former article I omitted to emphasize the 

 device of nature by which she accomplishes, in the only possible 

 way, the bringing the top, sides, throat, and belly of an animal to 

 the exact color of the surrounding earth, as well as to the same 

 degree of darkness. 



The animal's top is brown like the ground about him, and from 

 this brown his color grades steadily colder till it becomes cold 

 white on his under surfaces. The latter being in shadow and 



