356 LIFE-HISTORIES OF BIRliS 



grata, Clisiocampq, Americana, Colias pkilodice^ 

 arid many of the Noctuidise, Tortricidcs, and Tineidee 

 in their larval and perfect stages. 



The Cowbird delights to visit ploughed grounds, 

 where in small flocks it will glean for a long time, 

 unless disturbed. In pasture-grounds where the 

 cattle are grazing, it is a common visitor, nestling 

 among the cattle and sometimes alighting upon 

 their backs and relieving them of their dipterous 

 tormentors whith serve it as food; or else search- 

 ing among their droppings for the same. At 

 times it is somewhat rasorial. 



It has no attractions as a singer, and scarcely 

 deserves the name. Its notes are harsh and 

 unmusical. 



The species which seem to be the objects of its 

 special regard in this section, are comprehended 

 within the three families of the Sylvicdlidcs, Vireo- 

 nidcB, and Fringillidce. We have detected its eggs 

 within the nests of the following species: — 

 Geothlypis trichas, Dendrceca cestiva, SeiuriLs aii- 

 rocapillus, Sctophaga ruii cilia, Vireo olivaceus, V. 

 noveboraccnsis, V. gilvus, Spizclla socialis, Melospiza 

 melodia, and Cyauospisa cyanca. There is usually 

 but one <i.g^ deposited in the nest, although we 

 have frequendy discovered two, and but rarely 

 three. When the &gg is laid within the nest of 

 the Summer Yellow Bird, a remarkable degree of 

 sagacity is manifested when there is lacking ability 

 necessary to its removal. To frustrate the design 

 of its author by preventing its hatching, the birds 



