419. Merrill Parauque (Nyctidromus albicollis merrilli). L. 12; T. 6.2. Outer tail-feather without white. Two color phases, one gray, one rusty. Ad. ♂. Outer tail-feather black with sometimes a little rusty, next feather white on inner web, third feather white except at base. Ad. ♀. Outer tail-feathers brownish with broken rusty bars; next two with white at tip. Notes. A vigorous ker-whee-you repeated and sometimes running into a whit-whit-whit, ker-whee-you. Range.—Mexico north to southern Texas; winters chiefly south of Rio Grande. 420. Nighthawk (Chordeiles virginianus). L. 10; W. 7.8. Primaries blackish with a white bar and no rusty spots; darkest of our Nighthawks. Ad. ♂. Above black with white and buff markings; throat and band near end of tail white. Ad. ♀. Throat rusty, no white band in tail. Notes. A nasal peent; and in the breeding season, a booming sound produced by diving from a height earthward. Range.—Eastern United States, chiefly, breeds from Florida to Labrador, west and northwest to northern California, British Columbia, and Alaska; winters south of United States. 420a. Western Nighthawk (C. v. henryi). Similar to [No. 420], but markings above rusty and more numerous; belly washed with rusty. Range.—Western United States, east to the Plains, wintering south of United States; exact distribution unknown. 420b. Florida Nighthawk (C. v. chapmani). Similar to [No. 420], but smaller (L. 8.6; W. 7.1;) and paler; white and buff markings above larger and more numerous. Range.—Florida, west along Gulf Coast to eastern Texas; south in winter to South America. 420c. Sennett Nighthawk (C. v. sennetti). Similar to [No. 420b], but still paler, white and buff prevailing on back and scapulars; palest of our Nighthawks. Range.—Great Plains north to Saskatchewan; winters south of the United States. 421. Texan Nighthawk (Chordeiles acutipennis texensis). Wing quills with rusty spots; outer primary shorter than one next to it; belly conspicuously washed with rusty buff. Ad. ♂. Throat-patch and band near end of tail white. Ad. ♀. No white band in tail. Notes. A mewing call and a tapping accompanied by a humming sound. (Merrill.) Range.—Central America; breeding north to southern Texas, southern New Mexico, southern Utah, southern Nevada, and Lat. 38° in California; winters south of United States.

Swifts

422. Black Swift (Cypseloides niger borealis). L. 7; W. 6.5. Tail without spines, slightly forked. Ads. Sooty black, paler below; a black spot before the eye; forehead whitish. Notes. Generally silent. (Bendire.) Range.—Breeds from Central America north, in mountains of western United States, to British Columbia; east to Colorado; winters south of United States; more common in Pacific coast states. 423. Chimney Swift (Chætura pelagica). L. 5.4; W. 4.9. Tail with protruding spines. Ads. Above sooty, rump and underparts paler; throat whitish. Notes. A rolling twitter. Range.—Eastern North America, west to the Plains; breeds from Florida to Labrador and Manitoba; winters south of United States, to Central America. 424. Vaux Swift (Chætura vauxii). L. 4.5; W. 4.4. Ads. Similar to [No. 423], but smaller and somewhat browner. Notes. Resemble those of [No. 423], but are less frequently uttered. (Bendire.) Range.—Western United States; breeds on Pacific coast, locally, north to British Columbia; east casually to Montana and Arizona; winters south of United States to Central America. 425. White-throated Swift (Aëronautes melanoleucus). L. 6.5. Tail forked, without spines. Ads. Above sooty brownish black; breast, middle of belly and flank patches white. Notes. A sharp, metallic twitter. Range.—Western United States; east to western Nebraska and Black Hills; breeds in Rocky Mountains north to Montana; on Pacific coast north to Lat. 38°; winters south of United States to Central America.

Hummingbirds

426. Rivoli Hummingbird (Eugenes fulgens). L. 5.1. A small white spot behind eye. Ad. ♂. Crown purple, throat bright green, back bronzy green; tail somewhat more bronzy. Ad. ♀. Above bronzy green, all but central tail-feathers with blackish ends and narrow grayish tips; below grayish, all but throat feathers green centrally. Yng. ♂. Throat with more or less green, belly and above more bronzy than in ♀. Range.—Nicaragua, north in mountains to mountains of southeastern Arizona, and southwest New Mexico; winters south of United States. 429. Black-chinned Hummingbird (Trochilus alexandri). L. 3.5; W. 1.7. Ad. ♂. Chin and upper throat black, lower throat amethyst; tail forked, feathers pointed. Ad. ♀. Throat grayish white; chin buffy; tail feathers more rounded, three outer ones tipped with white. Yng. ♂. Similar ♀, but throat with dusky spots. Range.—Western United States; breeds from San Antonio, Texas, New Mexico, Arizona, and California north to Montana and British Columbia; rare on Pacific coast north of southern California; winters south of United States. 430. Costa Hummingbird (Calypte costæ). L. 3.1. No rusty in plumage. Ad. ♂. Crown, throat and lengthened neck-feathers amethyst, back dull green. Ad. ♀. Below grayish white; above grayish green; outer tail-feathers gray at base, then black and at tip white. Yng. ♂. Similar to ♀, but throat usually with some amethyst spots; tip of outer tail-feather grayish. Range.—Northwestern Mexico; breeds north throughout Lower California, to southern California, northern Nevada, southwestern Utah, and southwestern New Mexico; winters from Mexican border southward. 437. Lucifer Hummingbird (Calothorax lucifer). L. 3.6; B. .8. Ad. ♂. Throat purplish pink, feathers at its side much lengthened; tail feathers very narrow, the outer ones less than .05 in. wide on end half. Ad. ♀. Below nearly uniform rusty buff, above bronzy green; tail-feathers white-tipped. Range.—"From western Texas and southern Arizona south to the city of Mexico and Puebla." (Bailey.) 440. Xantus Hummingbird (Basilinna xantusi). L. 3.6. A white streak behind eye. Ad. ♂. Chin, forehead and cheeks black; throat green; tail rusty brown. Ad. ♀. Below uniform rusty, above green; outer tail-feathers rusty brown. Range.—Lower California, north to Lat. 29°; most common in Cape Region.

427. Blue-throated Hummingbird (Cœligena clemenciæ). L. 5.2. A white stripe behind, and a smaller one before eye. Ad. ♂. Throat blue; belly grayish; back green; tail blue-black, outer feathers broadly white tipped. Ad. ♀. Similar but throat dusky gray. Range.—Southern Mexico north. In mountains to mountains of southwestern New Mexico and southern Arizona; winters south of United States. 438. Reiffer Hummingbird (Amazilis tzacatl). L. 4.1. Ads. Above, throat and breast shining green; belly grayish; tail square, rusty brown, narrowly margined with coppery. Yng. Similar but more rusty above. Range.—Northern South America; north, rarely, to Lower Rio Grande Valley, Texas. 439. Buff-bellied Hummingbird (Amazilis cerviniventris chalconota). Similar to [No. 438], but belly rusty gray, tail forked and broadly margined with coppery green. Range.—Central America, north, in spring, to Lower Rio Grande Valley, Texas. 440.1. White-eared Hummingbird (Basilinna leucotis). L. 3.7. A white line behind eye. Ad. ♂. Chin, forehead and cheeks blue, throat and breast green, tail blackish bronzy green. Ad. ♀. Crown rusty, back bronzy green, below gray spotted with green; outer tail-feathers tipped with gray. Yng. ♂. Similar. Range.—Nicaragua north, in spring, through mountains to southern Arizona. 441. Broad-billed Hummingbird (Iache latirostris). L. 4. Ad. ♂. Above green; below darker; throat purplish blue; tail darker. Ad. ♀. Below gray; outer tail-feathers green at base, then bluish black tipped with gray. Yng. ♂. Similar to Ad. ♀, but tail blue black with faint gray tips; throat with metallic green feathers. Range.—Southern Mexico; breeds north through mountains to southern Arizona and southwestern New Mexico. 428. Ruby-throated Hummingbird (Trochilus colubris). L. 3.5; W. 1.5. Ad. ♂. Throat ruby, chin blackish; tail forked, the feathers pointed. Ad. ♀. Throat grayish, tail-feathers rounded, three outer ones tipped with white. Yng. ♂. Like ♀ but throat with dusky spots. (See [next page]) Range.—Eastern North America, west to about Long. 100°; breeds from Florida and eastern Mexico, north to Labrador and Hudson Bay region; winters from southern Florida to Central America.