THE GENUS CHOKDEILES SWAINSON OBERHOLSEB. 59 



central northern Kansas; southwestern Nebraska; Wray and Love- 

 land, northeastern Colorado; Laramie Peak, southeastern Wyoming; 

 Greybull and Germania in Bighorn County, northwestern Wyoming ; 

 west to Germania and Fort Bridger, western Wyoming ; and Parley's 

 Park, Wasatch Mountains, central northern Utah; south to the 

 Uinta Mountains, northeastern Utah; Grand Junction, central west- 

 ern Colorado; Twin Lakes, central Colorado; the Rio Grande and 

 Trinidad, central southern Colorado; Sierra Grande and Cuervo, 

 northeastern New Mexico; Hereford and Lamb County, northwest- 

 ern Texas; San Angelo and Giddings, central Texas; east to Gid- 

 dings, central Texas; Terrell and Bonham, central northern Texas; 

 Lawton, central southern Oklahoma ; Cairo, Hamilton, Turkey Creek, 

 and the RejDublican River, middle Kansas. Migrates through eastern 

 Mexico and Central America, and casually east to Grant County, 

 southwestern Minnesota, and Warsaw, western Illinois. Winters 

 probably in South America. 



Remarhs. — The male of this new race differs from that of CJwr- 

 deiles mrgimanus henryi in lighter upper surface, particularly on 

 the scapulars and tertials, the dark areas being more brownish (less 

 blackish) and the light markings finer and usually much less deeply 

 tawny or ochraceous; and in the lighter lower surface, which is less 

 deeply buffy on posterior portion and less rufescent on the anterior 

 part. From Cliordeiles virginianus hesperis he may readily be dis- 

 tinguished by his much paler upper parts, the dark brown areas less 

 blackish, the light mottlings much more numerous ; and by the paler, 

 anteriorly less rufescent, posteriorly more buffy, and more narrowly 

 or brokenly barred lower surface. He is so very different from Chor- 

 deiles virginianus virgimanus by reason of his much paler, more 

 brownish, and much more numerously ochraceous- and buffy-marked 

 upper parts; lighter, less blackish (more brownish) anterior lower 

 surface ; and lighter, less heavily barred breast and abdomen, that he 

 is distinguishable almost at a glance. 



The female is usually more brownish, decidedly more mottled with 

 ochraceous on the upper parts, and much more buffy below than is 

 the male. This makes the female more closely resemble the female 

 of Chordeiles virginianus henryi than the male does the male of 

 Chordciles v. henryi, but she nevertheless is separable from the 

 female of Chordeiles v. henryi by her lighter, more rufescent (less 

 blackish) brown upper parts, with paler, usually finer and more 

 numerous markings; and by the lighter jugulum (both as regards 

 the ground color and the tawny and buff markings), throat, and 

 posterior lower parts. From the female of Chordeiles virginianus 

 sennetti she may be distinguished on the upper parts by her much 

 more brownish (less grayish) and lighter ground color, and much 

 more ochraceous light markings; and below by the more rufescent, 



