The Swifts 



Distribution. — Lower California and extreme south- 

 ern California. 



Division 111. Scales of back small and of uniform size — 

 bluntly keeled. Tail with larger, spiny scales. 



stansbury's swift, U. slansburiana, Baird & Girard. 



Dark green or grayish, with two series of small, dark 

 blotches on the back, which are surrounded by scat- 

 tered, bluish dots. A pale band on the side, and 

 frequently a dark, brownish blotch behind the fore- 

 limb. Abdomen pale. One of the smallest species. 

 Following are the measurements of an adult specimen: 

 Total length, 4} inches; length of tail, 2} inches; 

 width of body, i an inch; width of head, I of an inch. 

 Distribution. — The most abundant species of the 

 genus. It occurs from western Texas to Cali- 

 fornia, inclusive, and northward to Nevada. 

 Very common in the deserts of Arizona and 

 eastern California. 



palmer's swift, U. pahnerii, Stejneger. 



Larger than the preceding. Bluish-drab, with numerous, 

 small, whitish dots, two to three scales large, irregu- 

 larly scattered over the body. No dark blotches on 

 the hack. A dark spot behind the forelimb. Attains 

 a length of about 6 inches. 

 Distribution. — San Pedro Martir Island, Gulf of 

 California. 



Division IV. Middle of the back with four to six rows of 



much enlarged, keeled scales. 

 Sub-division a. Enlarged scales of the back in five or six 

 irregular rows — smaller intermixed with larger ones. 



1. A row of sharply conical, close-set scales on each side. 

 ORNATE SWIFT, U. omata, Baird & Girard. 



Gray, with wavy, black cross-bands. Males with a large 

 blue patch on each side of the abdomen. Head broad. 

 Hind limbs shorter than the distance from vent to 

 fold of skin under neck. Attains a length of six to 

 eight inches. 

 Distribution. — Arid regions of New Mexico, Arizona 

 and California. 

 \a. No row of raised scales on the sides. 



OLIVE SWIFT, U. levis, Stejneger. 



Large scales of the back very feebly keeled. Greenish 

 above, without traces of other markings. The male 

 has a blue patch on each side of the abdomen. 

 Distribution. — New Mexico. Rare. 

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