2io VERTEBRATES: BIRDS. 



The Mexican Junco, J. clncrcus, Cab., of Mexico, is six 

 and two fifths inches long, the wing over three inches. 



The Oregon Snow-Bird, J. orcgonus, Sclat., of the Pa- 

 cific coast to the eastern side of the Rocky Mountains, is 

 six and a half inches long, wing three inches, the head 

 and neck all round sooty black, the interscapular region 

 and the wings dark rufous brown, a lighter tint of the 

 same on the breast and below, the rump brownish ash, 

 and the outer two tail-feathers white. 



The Gray-headed Snow-Bird, J. canlccps, Baird, of the 

 Rocky Mountains, is six inches long, the wing about three 

 and a quarter inches. 



The Black Snow-Bird, J, hy emails, Sclat., of the United 

 States east of the Missouri, is six and a quarter inches 

 long ; grayish or dark ashy-black, deepest before ; the 

 middle of the breast and belly, the under tail-coverts, 

 and the first and second external tail-feathers white, and 

 the third tail-feather white margined with black. These 

 birds appear in flocks in winter, and are very tame. 



The Genus Poospiza is represented by only two species 

 in the United States. 



The Black-throated Sparrow, P. bilineata, Sclat., of the 

 Rio Grande, is nearly five inches long, the wing two and 

 three quarters inches ; the color above ashy gray, the 

 under parts and superciliary stripe white, the chin and 

 throat black. 



Bell's Finch, P. Belli, Sclat, of Southern California, 

 is six and a quarter inches long, the wing nearly three 

 inches ; the upper parts bluish ash, under parts pure 

 white. 



The Genus Spizclla is distinguished from Zonotrichia 

 by the smaller size, and a longer and forked tail. 



The Tree Sparrow, 5. monticola, Baird, of North Amer- 

 ica, is six and a quarter inches long, the wing three inches ; 

 the feathers of the back dark brown centrally, then rufous, 



