THE BIRD BOOK 
420c. Sennett’s Nighthawk. 
Cordeiles virginianus sennetti. 
• * 
420 — 421 
of gray, brown and lilac. 
421. Texas Nighthawk. 
Chordeiles acutipennis texensis. 
Range.- — Mexico and Central America, breed 
ing north to southern Utah and California. 
The pattern of the 
marking of this species 
is finer and more mot- 
tled with rusty than 
the Nighthawk. Its 
habits do not differ to 
any extent from those 
of the preceding spe- 
cies; they lay their two Grayish white 
mottled gray eggs up- 
on the bare ground, often on the dry sand and 
in arid regions 
where they are 
exposed, with 
no protection, 
to the scorch- 
ing rays of the 
sun. The eggs 
vary endlessly 
in extent of 
markings, some 
being very pale 
and others 
very dark gray, 
mottled with 
various shades 
Size 1.10 x .75. 
Range. — A very pale species with little or 
no tawny; found in the Great Plains from 
Texas north to the Saskatchewan; winters 
south of the United States. 
SWIFTS. Family MICROPODID^ 
422. Black Swift. Cypseloides niger 
borealis. 
Range.— Mountain ranges from Central Amer- 
ica north to British Columbia, locally distribut- 
ed throughout its range. 
The plumage of this Swift is entirely sooty 
black, darkest above; the tail is slightly forked 
and is without spines; length of bird, 7 inches. 
Although the general habits of this species are 
well known, little is known of their nesting; 
they are seen during the breeding season about 
the higher ranges throughout their United 
States habitat, and are supposed to nest in 
crevices on the face of cliffs at a high altitude. 
268 
422 — 424 
