walking after the grazing cattle and feeding upon the insects dislodged from the grass by their cropping. Other birds build a home and seek a mate, often remaining with the same one a lifetime. The Cowbirds are polygamous, liv. ing in roving flocks, building no nests, and providing in no way for their offspring. When the laying impulse seizes them, they slyly deposit the egg in the nest of some smaller bird. This shows forethought, however; for there is less likelihood of the eggs being thrust out, and it also obtains a greater share of warmth than the other eggs in the nest and hatches more rapidly.
Many birds do not allow themselves to be so imposed upon, and either eject the strange egg, build a new nest over it, or abandon their nest entirely; others seemingly less intelligent will rear the ungainly stranger, even though from its greater size and appetite it crowds and starves the legitimate tenants of the nest. I have many and many a time seen a young Cowbird, after leaving the nest, being fed by a bird so much smaller than itself that the poor foster parent had to stand on tiptoe.
Cowbirds' eggs have been found in the nests of the Chat, Baltimore Oriole, Wood Thrush, Mourning Dove, Kingbird, Towhee, Vireos, Warblers, and all the Sparrows, and even in the secluded hut of the Ovenbird, while many nests are so unfortunate as to contain more than one of these eggs.
Vagrants as the Cowbirds are in the breeding-season, after the nesting the young do not continue with their foster parents, but return to the flocks of their progenitors, and remain with them. Thus these Cowbirds are the socialists among birds, and are like their human prototypes, who send their young to free kindergartens and mission schools that they may be fed and clothed at the expense of others; then drawing them surely back, with their inherited principles unchanged. Some evils are inextrieably mixed up with the foundations of things.
168
