258 SINGING BIRDS — OSCINES. 



Female, light olivaceous-brown all over, lighter on the head and beneath. Length, S.fifi ; 

 extent, 13.60 ; wing, 4.40 ; tail, .3,40. Iris brown ; bill and feet black. 



Hah. United States from the Atlantic to California ; not found immediately on the 

 coast of the Pacific. 



I think that a few of thi.s .specie.? pas.s the winter in the Colorado 'S'allcy, 

 and, perhaps, also in the San Joaquin VaUey, Init I have not seen them at 

 any time in those nearer the coast. In the country east of the Sierra 

 Nevada they probably wander as far north as the Columbia Elver, as they 

 follow wagon-trains along the Platte in great flocks, and may be expected to 

 accompany them farther west. 



The remarkable habit of this bird of laying its eggs in the nests of other 

 birds, instead of Iniilding for itself, relieves it from the usual necessity of pair- 

 ing in the spring, and it remains gregarious at all seasons, though generally 



Female. 



the flocks are not large, except in autumn. They seemed to be migrating 

 northward through the Colorado Valley early in April, and on the 19th of 

 that month I found an egg of this bird in a nest of the yellow-breasted chat 

 {Idcria), showing that some of them are raised in the lat. of 35°, as well as 

 northward. 



According to Nuttall, the sexes are polygamous, not even pairing like 

 other small liirds for one year. In the East he found their eggs oftenest in 

 the nests of the Vino olivaceus, GcotUypis trichas, Spizclla socialis, Dcn- 

 drmca ccstiva, ruliopfila ccerulea, and other species corresponding to our 

 Vireo Huttoni, Sialia Mcxicana, Cyanospiza, amana, Mclospiza Hccrmanni, 

 Sayornis nigricam, and Turdus nanus, all of which may be supposed to act 

 as nurses for this foundling bird in California. Though all much smaller 

 than the cow-bird, and building in very diflerent situations, the foster-parents 

 usually take good care of the large egg found in their nest, especially if 

 laid after one of their own, ami frequently Ijegin to sit immediately, although 



