TEXAS NIGHTHAWK.
421. Chordeiles acutipennis texensis. 10 inches.
The markings of this species are much finer and more mottled with a reddish brown color than the preceding. They are very abundant in Arizona, southern Texas and quite common in southern California.
BLACK SWIFT.—Family Micropodidæ.
422. Cypseloides niger borealis. 7 inches.
The plumage of the Swift is a dull sooty black, somewhat lighter on the under parts. The tail is slightly forked and does not have the spines which are usual with this family. Although the general habits of this species are well known, but little is known of their nesting; they are seen during the breeding season about the higher ranges of their United States range, and are supposed to nest in the crevices of cliffs at high altitudes.
VAUX SWIFT.
424. Chætura vauxi. 4½ inches.
This small Swift is not nearly as common as the preceding, is much paler in color and white on the under parts and throat. Their habits are much like the last, only that they make use of hollow trees in which to place their nests, which are made of twigs glued to the tree with the glutinous saliva of the birds, forming a very shallow platform in which they deposit three or four pure white eggs. They are on the wing much of the time during the day catching insects, or several pairs seemingly at play in the air, generally at quite high elevations, toward dusk returning to their nesting places.