TELE; WHITE-THROATED SWIFT. 455 
is undertaken even as late as August if the first has proven unsuccessful” 
(Birds of Ohio). 
Save in the matter of nesting, the Vaux Swift does not differ 
essentially in habit or appearance from the well-known Chimney Swift, 
referred to in the preceding paragraphs. It is, however, very much less 
common and is only of local distribution, chiefly in the lower mountain 
valleys. Local attachments are doubtless largely determined by the presence 
of large cottonwood timber, but the birds descend to the lowlands, especially 
after the close of the nesting season, in small roving parties, somewhat after 
the fashion of the Cloud Swifts, with which indeed they frequently asso- 
ciate. They have thus been regularly reported by West-side observers at 
Tacoma, Seattle, and Bellingham, and I have seen them at Blaine, and in 
the valleys of the Nooksack (at Glacier), Skagit, Nisqually (in Rainier 
National Park), and Quillayute Rivers. The only East-side records appear 
to be those from the north fork of the Ahtanum, in Yakima County, and 
the valley of the Stehekin, in Chelan County. 
Vaux’s Swift with us nests only in the hollow recesses of tall dead 
cottonwood trees, where they glue a shallow bracket of broken twigs, 
cemented with hardened saliva, to the curving inner wall. In California, 
however, they are said to be adopting the ways of civilization, and are be- 
ginning to nest in chimneys, after the fashion of C. pelagica. 
No. 161. 
WHITE-THROATED SWIFT. 
A. O. U. No. 425. Aeronautes melanoleucus (Baird). 
Synonyms.—Rock Swrrt. Mountain Swirt. Rocky Mountain Swirt. 
WHITE-THROATED Rock SWIFT. 
~ Description— Adults: Plumage black (variable, sooty brown to glossy 
black) ; forehead and line over eye paler; lore velvety black; chin, throat, breast, 
and belly, centrally, white—also outer edge of outer primary, tips of secondaries, 
lateral tail-feathers, and a conspicuous patch on flank, sometimes nearly meeting 
fellow across rump; bill black. Length 7.00 (177.8) or under; wing 6.50-7.00 
(165.1-177.8) ; tail 2.65 (67.3). 
Recognition Marks.—Sparrow size but larger to appearance; exceedingly 
rapid flight with flashing white underparts and flank patches distinctive. 
Nesting.—‘“The nest is securely placed far in holes or crevices of rocks or 
indurated earths, usually at a great height; it is a saucer-like structure, about 
5x2 inches, with a shallow cavity, made of various vegetable materials well 
glued together with saliva, and lined with feathers. Eggs several, in one instance 
