first learn to look at them not solely from the point of view of man, who neither 

 flies nor climbs nor crawls, but also from that of the other animals, big and 

 little, winged and creeping, with whom the bearer of the costume in question 

 has in any way to deal. And by no other phenomenon of obliterative colora- 

 tion is this fact so forcibly brought home to one's mind as by the perfectly 

 consistent and unbrokenly intergraded chain of sky-picturing and ground-pic- 

 turing patterns and costumes of birds and mammals. 



One more notable phase of sky-picturing' s occurrence on birds must here 

 be cited, namely, its part in the costumes of some ground birds of the open 

 land. The American Bobolink (Dolichonyx oryzivorus) for instance, in the 

 summer plumage of the male, is marked and colored much like a skunk — as 

 its colloquial name "Skunk Blackbird" attests. Roosting at night in weeds 

 and grasses some inches above the ground — as it almost certainly does — it is 

 disguised, for the eyes of prowling predators, almost exactly as the skunk, 

 himself a prowling hunter, is disguised for the eyes of smaller ground animals. 

 The Black Lark Bunting (Calamospiza melanocorys) of middle western North 

 America, likewise a bird of the open ground, has a big, sky-matching white 

 patch on its wings; and several Longspurs (Calcarius, etc.) and Larks (Alau- 

 didce) have markings of the same nature, and kindred habits. 



Sky-picturing marks are sometimes found in evident cooperation with 

 wholly different disguising effects. Thus the common American Raccoon 

 (Procyon lotor) has a rim of white or very pale brown bordering its largely 

 dusky face ; and though in many views this must serve as an obliterative sky- 

 matching mark, like the many kindred markings of grubbing carnivorous and 

 half-carnivorous mammals, yet it also admirably serves to make the Raccoon's 

 whole face and head, in front view, look like the end of a hollow log or stump, 

 with a shadowy, dark interior and light, encircling outward rim. (See Fig. 120, 

 No. 36.) This trick of coloration, which has already been mentioned in con- 

 nection with the sloths (Chapter XX), is of widespread and frequent application 

 in the animal kingdom, as a glance at Fig. 1 20 will convince the reader. Here 

 we have many kinds of 'holes' with encircling light rims or margins; some 



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