290 CALIFORNIA ACADEMY OF SCIENCES, 



portion of the feathers of the neck of Corvus cryptoleucus, 

 and no way of accounting for it can be suggested. 



FAMILY ICTERID^. The Blackbirds, Orioles, etc. 



Yellow, red and black are emphatically the colors of 

 this family, with brown as the generalized shade. White 

 is almost completely excluded except in the bobolink 

 (Dolichonyx), which, in respect to its colors, is more 

 closely allied to the Fringillidse than to this group. 

 Nearly all the genera are very highly developed in their 

 colors, in most instances the specialized colors covering 

 the entire body. 



Genus Dolichonyx. The Bobolinks. 



(5) Male in breeding plumage differs from female; 

 young with peculiar first plumage, but similar to that of 

 adult female. 



Prevailing colors, black, white, buffy, gray, brown. 



I am utterly at a loss for any explanation of the colors 

 of this bird either in accordance with the general laws 

 of growth or any principle of utility. The only resort 

 is to suppose the breeding plumage of the male to be 

 wholly the result of sexual selection, but this seems to 

 be a very unsatisfactory means of accounting for it. 

 Mr. Frank M. Chapman* has described the manner in 

 which the breeding plumage of the male is assumed, 

 partly by a moult and partly by the wearing away of the 

 tips of the feathers. 



Genus Molothrus. The Cowbirds. 

 (8) Adult male more conspicuously colored than 

 female; young with a peculiar first plumage. 

 Prevailing colors, black, brown, gray, buffy. 

 The young plumage with the breast lighter colored 



''Ank, vii, pp. 120-124. 



