THE GENUS CHORDEILES SWAINSON OBERHOLSEE. 65 



CHORDEILES VIRGINIANUS HENRYI Cassin. 



Chordeiles henryi Cassin, Illust. Birds Cal., Texas, Ore., Brit, and Russ. 

 Amer., vol. 1, 1855, p. 239 (Fort Webster, N. Mex.). 



Chars, suhsp. — Similar to Chordeiles virginianus howelli^ but up- 

 per surface, both ground color and markings, much darker, the 

 latter more tawny and also coarser; lower parts posteriorly more 

 buffy, anteriorly more rufescent. 



Iris dark brown ; bill black ; feet gray. 



Measurements. — Male: Total length (in flesh), 228.G-243 (average, 

 236.2 mm.; 1 extent of wing, 535.9-61T.5 (596.6). ^ 



Female: Total length (in flesh), 222.3-241.3 (232.5) ;2 extent of 

 wing, 573-603.3 (593.7). ^ 



Male 4; Wing, 188-209.5 (average, 199.7) mm.; tail, 104-116.5 

 (111.1) ; exposed culmen, 6.5-7.5 (7.0) ; tarsus, 13.9-15.8 (14.6) ; 

 middle toe, 14-16.5 (15). 



Female ^- Wing, 182-198 (189.5) ; tail, 102.5-117.5 (110) ; exposed 

 culmen, 6.0-7.5 (6.6) ; tarsus, 12.5-14.8 (14.1) ; middle toe, 13.2-16 

 (14.7). 



Type-locality. — Fort Webster, southern New Mexico. 



Geographical distrihution. — Southwestern United States and ex- 

 treme northwestern Mexico ; south in migration through Mexico, prob- 

 ably to South America. Breeds in the Lower Austral, Upper Austral, 

 Transition, and Canadian zones, north to Taos, central northern New 

 IMexico; Montrose, southwestern Colorado; Keam's Canyon in Navajo 

 County, San Francisco Mountain, and the Hualapai Mountains, in 

 north central Arizona; west to Mellen, central western Arizona; 

 Prescott, central Arizona ; Picacho Peak, south central Arizona ; and 

 Nogales, central southern Arizona ; south to Nogales, central northern 

 Sonora; Babicora, central western Chihuahua; and Alamito (Pre- 

 sidio County), central western Texas; and east to Fort Stockton and 

 Pecos City, central western Texas; Carlsbad and Roswell, south- 

 eastern New Mexico; with Santa Rosa and Glorieta, north central 

 New Mexico. Migrates through Mexico, east to Tamaulipas, and 

 west to Jalisco, and presumably through Central America. Winters 

 probably in South America. 



Remarhs. — The present race proves not to be relatively so light, 

 particularly on the upper parts, as it has credit for being, and is 

 darker than any of the other western United States forms excepting 

 Chordeiles virginianus hesperis. The male is similar to the same sex 

 of Chordeiles virginianus hesperis., but is lighter, more brownish 



1 Ten specimens. 



2 Six specimens. 



^ Five specimens. 



* Eleven specimens, from Arizona and New Mexico. 



6 Twelve specimens, from Arizona, New Mexico, and Chihuahua. 



