ICTERIDyE — THE ORIOLES. ] 57 



^Ir. Xuttall staies that if a ( Vnv Jilackliinl's egg is deposited in a iu>st- alone 

 it is luiifoniily forsaken, and he also enumerates the Sunimcr Yellowhird as 

 one of tlie nurses of the Cowl)ird. In botii respects I think he is mistaken. 

 So far from forsaking her nest when one of these eggs is deposited, the Eed- 

 eyed Vireo has been known to commence incubation without having laid 

 any of her own eggs, and also to forsake her nest when the intrusive egg 

 has been taken and her own left. The D. a:Miva, I think, invariably covers 

 up and destroys the Cowbird's eggs when deposited behjre her own, and even 

 when deposited afterwards. 



Tlie Cow Blackbird has no attractions as a singer, and has nothing that 

 deserves the name of song. His utterances are harsh and unmelodious. 



In September they begin to collect in large tlocks, in localities favorable 

 for their sustenance. The Fresh Pond marshes in Cambridge were once 

 one of their chosen places of resort, in which they seemed to collect late in 

 September, as if coming frona great distances. There they remained until 

 late in October, when they passed southward. 



Mr. Eidgway only met with this species in two places, the valley of the 

 Humboldt in September, and in June in the Truckee Valley. Tlieir eggs 

 were also obtamed in the Wahsatch Mountains, deposited in the nest of Pas- 

 serella schistacea, and in Bear Kiver Valley in the nest of Gmililypis trichas. 



Mr. Boardman informs me that the Cow Blackljird is a very rare bird in 

 the neighborhood of Calais, Me., so much so that he does not see one of 

 these birds once in five years, even as a bird of passage. 



The eggs of this species are of a rouuded oval, tliough some are more 

 oblong than others, and are nearly equally rounded at either end. TJiey 

 vary from .8.^) of an inch to an inch in length, and from .65 to .70 in breadth. 

 Their ground-color is white. In some it is so thickly covered with fine dot- 

 tings of ashy and purplish-brown that the ground is not distinguishable. In 

 others the egg is blotched with bold dashes of purple and wine-colored 

 brown. 



On the Eio Grande the eggs of tlie smaller southern race were found in 

 the nests of Virco helli, and in each of tlie nests of the Vino pusillus found 

 near Camp Grant, Arizona, there was an egg of this species. At Cape St. 

 Lucas, Mr. Xantus found their eggs in nests of the Polinptila vidanura. 

 We have ui' information in regard to their habits, and can only infer that 

 they must be substantially tlm .'^,ame as those of the nortiiern l)irds. 



The eggs of the var. obscnrus exhibit a very marked \ariatiou in size from 

 those of the var. pecoris, and have a different appearance, though their colors 

 are nearly identical. Tiieir ground-color is wliite, and their markings a 

 claret-brown. These markings are fewer, smaller, and less generally dis- 

 tributed, and the ground-color is much more apparent. They measure 

 .60 by .55 of an inch, and their capacity as compared witli the eggs of the 

 ■pecoris is as 33 to 70, — a variation that is constant, and apparently too large 

 to be accounted for on climatic difl'ereuces. 



