ORIOLES. 255 



inches long. $ , iridescent black ; head of a warm silky 

 brown. $ , smaller, entirely brown ; beneath, paler (and of- 

 ten streaky ?). 



b. The eggs average .90 X .65 of an inch, though greatly 

 varying in size, and are white, thickly sprinkled, or finely 

 blotched, with brown and generally faint lilac. 



c. The Cow-birds, like the Cuckoos of Europe, 10 present 

 a most interesting phenomenon in nature, for, instead of pro- 

 viding for their young, they deposit their eggs in the nests of 

 other birds. They are also, unlike all our other birds, poly- 

 gamous, being equally without conjugal or parental affection. 

 I shall here follow their history from the earliest period of 

 their life, when they are left to the mercies or care of their 

 foster-parents, among whom I may enumerate, from my own 

 observations, the Bluebirds, Golden-crowned "Thrushes," 

 Maryland "Yellow-throats," Black and White "Creepers," 

 Summer Yellowbirds, several other Warblers, Red-eyed and 

 White-eyed Vireos, " Chippers," several other Sparrows, and 

 the Pewees ; also, on the authority of others, the Goldfinches, 

 Meadow Larks, and Brown Thrushes. Commonly one egg, 

 sometimes two, and rarely three, or even four, are found in the 

 chosen nest. I am satisfied, from indirect evidence, that the 

 eggs are often laid near the nest, if on the ground, and after- 

 wards placed in it. Generally they are laid later than those 

 of the rightful owners, though sometimes earlier. The pro- 

 prietors, on discovering the intrusion, occasionally destroy the 

 foundling, still more rarely build over it a second story, or 

 even a third, which becomes the nursery for their own young, 

 or, in some cases, even desert their home ; but more often, after 

 manifestations of their displeasure, they adopt the helpless 

 stranger. As the Cow-bird's egg is almost invariably some- 

 what larger than others in the nest, it receives a larger share 

 of warmth, in consequence of which the others frequently 

 become stale, when they are removed and destroyed by the 

 parents. Even should the legitimate eggs receive an equal 

 share of warmth, those of the parasite are first hatched, since 



100 Our Cuckoos, who build their own nests, have been called "Cow-birds " 

 from their notes. 



