BIBDS OF FIELD AND GARDEN. 321 



Throughout the season the sexes intermingle promiscu- 

 ously, from the time the females arrive in the spring. As 

 usual with other species, the males come first, and may be 

 seen singly, in small iiocks, or with other species of Black- 

 birds. They perch in the tops of tall trees, and their only 

 song is a long, thin whistle, high keyed and little varied. 

 The common note is a chuck. 



The females soon arrive from the south, and then flocks 

 may be seen in which they usually predominate. The eggs 

 are deposited from April to June, in the nests of other and 

 usually smaller birds. An egg is dropped slyly when the 

 owner of the nest is absent, and generally after she has laid 

 some of her own. Sometimes the little foster mother refuses 

 to adopt 'the offspring of another, and abandons the nest, 

 or builds another nest above the first one ; but usually she 

 good-naturedly settles down upon her nest to incubate. 



The Cowbird's egg is larger than those of the foster mother, 

 and is commonly deposited in the center of the nest. Per- 

 haps it gets more heat than the other eggs, for it hatches first. 

 The young Cowbird grows faster than the other chicks, and 

 gets about all the food. It is soon able to dislodge its smaller 

 and weaker foster brothers and sisters, who perish ; then the 

 young Cowbird monopolizes the entire time and care of its 

 foster parents. It is no uncommon thing to see a small War- 

 bler or a Chipping Sparrow feeding a young Cowbird twice 

 its own size ; but as soon as the stranger is well able to 

 shift for itself, it joins a flock of its own species. 



Grasshoppers seem to be its favorite animal food, but leaf 

 hoppers, also very destructive to grass, are freely taken. 

 Undoubtedly the Cowbird is of great benefit to pastures, 

 where it follows the cattle about, picking up insects that 

 start up around them. Weevils and curculios are commonly 

 eaten ; also caterpillars, but to a less extent than other Black- 

 birds eat them. Cowbirds take wasps, ants, and flies in small 

 quantity, and a number of spiders. Vegetable food, however, 

 forms the main part of the Cowbird's subsistence in spring 

 and fall, and, according to Professor Beal, it constitutes 

 nearly seventy per cent, of all the food for the year. A 

 large part of this, however, is weed seed, of which the seed 



