BIRDS OF JSrORTH AND MIDDLE AMERICA. 325 



dd. Sides of chest not extensively, if at all, blue, and feathers of lower. median 



portion of chest whitish, with indistinct grayish edges. 



e. Larger (adult male averaging wing 143, tail 147, exposed culmen 27, 



tarsus 43); no distinct white superciliary streak. (Southern portion of 



Mexican plateau, in States of Tlaxcala, Vera Cruz, Puebla, and Oaxaca.) 



Apheloooma sumichrasti (p. 336) 

 ee. Smaller (adult male averaging wing not more than 133.5, tail 146, exposed 

 culmen 27.5, tarsus 40.5); a distinct while superciliary streak. 

 /. Darker, the blue of a light cobalt or azure hue, back and breast dis- 

 tinctly brownish gray; bill and feet much stouter (exposed culmen of 

 adult female averaging 26, depth of bill at base 9.5, tarsus 39.5). 

 (Southwestern Texas, from Davis Mountains east to Kerr County.) 



Aphelocoma texana (p. 337) 

 /■.^ Paler, the blue of a light grayish cerulean hue, back and breast ashy 

 gray; bill and feet much more slender (exposed culmen of adult 

 female 25, depth of bill at nostrils 8, tarsus 38). (Southern Chi- 

 huahua.) Apheloooma grisea (p. 337) 



hb. Tail decidedly shorter than wing; no streaks on throat or che.st, the under 

 parts being plain grayish, deeper on chest, paler (oft#,n white) posteriorly. 

 (.-. Tail distinctly rounded at tip. (Ajihelocomn siehi'i-ii.) 



li. Larger (wing of adult male averaging more than 166, tail a\rraging more 

 than 146). 

 ('. Brighter colored, the pileum, liindiierk, wingt;, upper tail-coverts, and 

 tail distinctly blue. 

 /. Darker, the blue of a cobalt hue; posterior under parts jiale grayish, 

 even the under tail-coverts at least partly gray. (Southern portion of 

 Mexican plateau, in States of Vera Cruz, Puebla, southern Hidalgo, 

 Mexico, Morelos, and Michoacan. ). Apheloooma sieberii sieberii (p. 338) 

 ff. Paler, the blue of a cerulean hue; posterior under parts white, the under 

 tail-coverts pure white or with the longer ones but slightly grayish. 

 g. Larger, except bill and feet (wing of adult male averaging 178, tail 

 158.5); breast, etc., more brownish gray. (Southwestern part of 

 Mexican plateau in States of Jalisco and Colima. ) 



Apheloooma sieberii colimee (p. 339) 



gg. Smaller, except bill and feet (wing of adult male averaging 167, tail 



146.5); breast, etc., more bluish gray. (Northeastern portion of 



Mexican plateau, in States of Hidalgo, eastern San Luis Potosi, 



southern Tamaulipas, southern Coahuila, and eastern Zacatecas. ) 



Apheloooma sieberii potosina (p. 340) 



ee. Duller colored, the pileum, hindneck, wings, tail, etc., dull grayish blue. 



(Southern Arizona and New Mexico; northern Chihuahua and Sonora. ) 



Apheloooma sieberii arizonse (p. 340) 

 dd. Smaller (wing of adult male averaging less than 158.5, tail averaging less 

 than 139.5). 

 e. Larger, with smaller bill (wing of adult male averaging 158, tail 136, 

 exposed culmen 26.5, depth of bill at nostrils 9.5); coloration slightly 

 paler. (Northwestern and central portion of Mexican plateau, in States 

 of western San Luis Potosi, Zacatecas, northern Jalisco, southwestern 



Chihuahua, and Sinaloa.) Apheloooma sieberii wollweberi (p. 341 ) 



ee. Smaller, with larger bill (wing of adult male averaging 146, tail 126.5, 

 exposed culmen 29, depth of bill at nostrils 10); coloration slightly 

 deeper. (Northeastern Mexico, in State of Nuevo Leon and north to 



Ohisos Mts., southwestern Texas.) 



Apheloooma sieberii couchi (p. 342) 



cc. Tail even or truncated at tip. ("Mexico.") .Apheloooma ultramarina (p. 343) 



