The Cowbirds 



flight. And to these a low, rambling song, delivered sotto voce, — your 

 jay of whatever species is always modestly "practicing" — and you have 

 quite an extended repertory. 



Although common enough on Mt. Shasta, and of regular occurrence 

 through the heavy forests of the northwestern counties, the eggs of 

 Perisoreus jays have only once been reported from this State. The bird 

 builds a very substantial nest of twigs, grasses, plant-fiber, and mosses, 

 without mud, and it provides a heavy lining of soft, gray mosses for the 

 gray-green eggs. The nest is placed, usually, in a fir sapling, at a 

 height ranging from ten to eighty feet, and so well concealed that its 

 discovery is well nigh impossible, save for the visits of the bird. Only 

 one brood is reared in a season, and family groups hunt independently 

 of their more distant kinsmen until late midsummer. 



No. 12 



Cowbird 



No. 12a Nevada Cowbird 



A. O. U. No. 495 part. Molothrus ater artemisiae Grinnell. 



Description. — Adult male: Head, neck, and throat broadly light seal-brown, or 

 bone-brown; remaining plumage black with metallic greenish or bluish reflections. 

 Bill, feet, and legs black; iris brown. Adult female: General color fuscous above and 

 drab below, the feathers chiefly with obscurely darker centers, or shaft-streaks, and 

 occasionally show'ng faint greenish reflections; head paler; throat drabby white, un- 

 marked. Very old birds are darker, with more iridescence and less streaking. 

 Immature birds resemble adult female, but are lighter and more varied; above brownish 

 gray (nearly hair brown), everywhere edged with grayish white; below grayish, heavily 

 streaked everywhere (save on throat), and especially on breast, with fuscous, and 

 varied by brownish buffy edgings. The young males present a striking appearance 

 when they are assuming the adult black, on the instalment plan, by chunks and blotches. 

 Length 190.5-203.2 (7.50-8.00). Average of 1 1 males from Humboldt County, Nevada, 

 (after Grinnell): wing 1 13.5 (4.55); tail 79.4 (3.13); bill 18.3 (.72); depth of bill at base 

 10.3 (.40); tarsus 27.7 (1.09). Females average decidedly less. 



Recognition Marks. — Towhee size; brown head and black body of male; blended 

 brown of female. Requires distinction from the resident Brewer Blackbird (Euphagus 

 cyanocephalus) , from which it differs in its much smaller size, brown instead of vio- 

 laceous head of male; shorter, more turgid beak; female with much lighter throat; and 

 posterior parts not glossy. Young Cowbirds bear a superficial resemblance to female 

 Redwings (Agelaius sp.), but are smaller and less sharply streaked. Close attendance 

 upon cattle distinctive. 



Nesting. — Parasitic: the Cowbird invariably deposits her eggs in the nests of 

 other birds. Eggs: I or 2, rarely 3 or 4, with a single hostess; white or grayish white, 

 sprinkled or spotted with grayish brown (Natal brown to fuscous, or buffy brown to 

 drab), if finely, then almost uniformly, if more coarsely, then sharply, and with tend- 



75 



