266 CALIFORNIA ACADEMY OF SCIENCES. 



important role to play than any utilitarian princij^le. 

 As is generally the case with long established groups, 

 the characters of the male have been generally either 

 completely or almost entirely transferred to the female, 

 while even the young vary little or not at all from the 

 adult. 



ORDER RAPTORES. BIRDS OF PREY. 



The birds of prey are eminently the despots of the 

 feathered realm. Having no formidable rivals outside 

 their own ranks, they have no need of protective colors, 

 these being absent in the entire group. Some species 

 are marked with agressive (anticryptic) colors, however, 

 enabling them to steal upon their prey unawares, but 

 the majority of them trust rather to the sharpness of 

 their eye and the fleetness of wing for their food. What 

 good would agressive colors be to an eagle swooping 

 upon a lamb, or a Cooper's hawk falling upon some 

 luckless chicken or rabbit? Nor would directive marks 

 be of any use, as a general rule, for these birds have no 

 enemies to escape from. It is a notable fact that bright 

 colors are wholly wanting in the order, and that there 

 are but few species in which an elaborate pattern of 

 coloration exists. A tendency towards melanism is 

 everywhere present, or else the color of the back is some 

 uniform shade of brown or gray, and the breast streaked 

 or barred with the same color. All this points to the 

 independence of these birds, so far as the color is con- 

 cerned, of utilitarian influences. The colors seem to 

 have been, for the most part, developed without the in- 

 terposition of natural selection, and simply in accord- 

 ance with the general principles of growth. The tail 

 is generally, and the head occasionally, colored with 

 recognition marks of some sort, discriminative, sexual, 

 socialistic, and possibly to a less extent directive. The 



