BLACKBIRDS, ORIOLES, ETC. 287 



GENUS MOLOTHRUS. 



General Characters. Bill short, stout, conic, about two thirds as long as 

 head, broad ridge running well up on forehead ; wings moderate or long 

 and pointed ; tail shorter than wings, even, or a little rounded ; feet strong ; 

 tarsus not shorter than middle toe with claw. 



KEY TO SPECIES. 



1. Length (male) 6.60-7.65 ater, p. 287. 



1'. Length (male) 6.00-7.10. Texas and Arizona . obscurus, p. 288. 



495. Molothrus ater (Bodd.). COWBIRD. 



Adult males. Head, neck, and chest uniform brown ; rest of plumage 

 glossy black with green and purple reflections. 

 Adult female : smaller than male, streaked 

 brownish gray, darker above, lighter on throat. 

 Young male : upper parts dull grayish brown Fi 



or dark brown, feathers bordered with pale 

 buffy or grayish brown and whitish ; under parts broadly streaked with 

 brownish, dull buffy, or whitish. Young female : like young male, but 



Ealer, under parts mainly dull buffy, streaked with grayish brown. Male: 

 mgth (skins) 6.60-7.65, wing 4.15-4.56, tail 2.76-3.15, bill .6S-.77. Female : 

 length (skins) 6.10-7.10, wing 3.68-4.12, tail 2.43-2.77, bill .60-.67. 



Distribution. From southern British America south throughout the 

 United States, breeding west to eastern Oregon ; migrating to eastern 

 Mexico. Less common in the western part of its range. 



Eggs. Deposited, usually singly, in nests of other birds, 8 to 12, whit- 

 ish, whole surface covered with brown specks and blotches, usually heaviest 

 about the larger end. 



Food. Mainly noxious weed seed and insects, with a small amount of 

 grain. 



" ' Buffalo bird' used to be one of the names of the cowbird on the 

 Plains, and Major Bendire says that in the prairie states now ' one 

 will rarely see a bunch of cattle without an attendant flock of cow- 

 birds, who perch on their backs, searching for parasites.' This 

 occupation is not interrupted by the ordinary cares of family life, 

 for the cowbird builds no nest of its own, but foists its offspring 

 upon its neighbors. 



" Probably the historic cause for this remarkable habit would give 

 us more charity for the. bird, but it does such violence to the one 

 redeeming instinct of the lowest types of man and beast, that it is 

 hard not to regard the bird with unqualified aversion. Not only is 

 it entirely lacking in the maternal but in the conjugal instincts, for 

 it practices polyandry. On the other hand, the male cowbird is 

 polygamous. . . . The only thing that can be said in favor of the 

 female cowbird is that she takes pains to place her eggs where they 

 are most likely to be hatched. Major Bendire gives a list of ninety- 

 one birds in whose nests she has been known to leave her eggs ; but 

 though this includes woodpeckers, flycatchers, orioles, thrushes, 



