434 MICHIGAN BIRD LIFE. 
TECHNICAL DESCRIPTION. 
Adult male in spring: Entire top of head glossy black; occiput, nape and hind neck 
rusty white, buffy, or pure white; outer scapulars, rump and upper tail-coverts white or 
whitish; interscapulars mainly black, usually streaked with rusty or whitish; entire under 
parts clear black except for whitish or rusty edgings on some feathers of abdomen and under 
tail-coverts; wings and tail pure black, the tertiaries rather broadly margined with whitish, 
and the first three primaries with very narrow white edges; bill bluish black; iris dark 
brown; legs and feet brown. 
Adult female in spring: Top of head deep brown, with a median stripe of grayish buff, 
which is also the ground color of the entire upper parts, but plentifully streaked and spotted 
with dark brown and blackish, most heavily on the scapulars and interscapulars; under 
parts clear buff or grayish buff, more or less streaked on sides, flanks and under tail-coverts 
with blackish, the chin nearly pure white; wings and tail brownish, with narrow light 
edgings; upper mandible reddish brown, lower flesh colored; feet and legs pale; iris light 
brown. 
Adult male in autumn: Similar to summer female, but the ground color a deeper, richer 
buff, and the streaking more pronounced. Autumn females, and young of both sexes, 
are similar but paler than the autumn male, the females usually separable by smaller 
size. 
Male: Length 7 to 7.60 inches; wing 3.50 to 4; tail 2.75 to 3; culmen about .55. Female 
averaging about one-half inch shorter, the wing about one-fourth inch less. 
196. Cowbird. Molothrus ater ater (Bodd.). .(495) 
Synonyms: Cow Blackbird, Cow Bunting, Lazy Bird, Brown-headed Blackbird.— 
Oriolus ater, Boddaert, 1783.—Molothrus pecoris, Aud., Bonap., Baird, and others.— 
Emberiza pecoris, Wils. 
Plate NLIV. 
Smallest of our blackbirds. Male, metallic greenish black, the entire 
head and neck brown; female, dirty grayish brown. 
Distribution.—United States from the Atlantic to the Pacific, north 
into southern British America, south in winter into Mexico. 
This, the smallest of our blackbirds, is abundant throughout the state 
and well known not only from its constant association with cattle in the 
pasture, where it is seen feeding about their feet and perching upon their 
backs, but also on account of the remarkable habit of laying its eggs in the 
nests of other birds. It never builds a nest of its own, nor does the female 
take any care whatever of its young. The birds are polygamous and are 
commonly found during spring and summer in small flocks of twenty or 
less in which the males may outnumber the females or vice versa. 
When the female is about to lay she searches for the nest of some smaller 
bird, preferably a warbler or a sparrow, and watching her opportunity 
deposits her egg in the nest while the owner is temporarily absent. Usually 
the owner of the nest accepts the situation and hatches the egg along with 
her own, and eventually the young cowbird is reared, very often at the 
expense of the other young; for, being larger, stronger and more voracious, 
the young Cowbird demands and receives the larger part of the food brought 
by the parents, so that, if not crowded out of the nest, the rightful young 
are often starved to death. That this is not always the case is shown by 
the fact that nests are occasionally found containing a single young Cowbird 
and two or more young warblers or sparrows all nearly or quite ready to 
leave the nest. It is much more common, however, to find a pair of warblers 
or vireos feeding a single young Cowbird. It is claimed that the Cowbird 
is careful to select a nest already containing eggs, but this certainly is not 
true in Michigan, since scores of deserted nests are found each year con- 
