108 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



Similar to Spinu-s but bill relatively smaller, or less produced,' and 

 none of the species with yellow at base of remiges nor rectrices. 



Owing to the circumstance that the numerous species of Spiniis and 

 AstragaUnus differ so much among themselves in structural details, I 

 am unable to give a better diagnosis of the present group than the 

 above. The difference between the two groups in style of coloration 

 seems all the more important when it is taken into consideration that 

 in other respects as to coloration there is a very great range of varia- 

 tion in both groups. 



KEY TO THE SPECIES AND SUBSPECIES OF ASTKAGALINUS. 



a. No yellow on outer surface of wing-coverfs nor remiges. 

 h. Under tail-coverts white; upper tail-coverts white or grayish; inner webs of 

 exterior rectrices with white at tips, but not at base nor in middle portion, 

 c. White or otherwise light-colored markings of wings and tail more restricted 

 (adult male averaging, wing, 72.64; tail, 46.99). (Eastern United States, 



west to Great Plains. ) Astragalinus tristis tristis (p. 109) 



cc. White or otherwise light-colored markings of wings and tail more extended. 

 d. Larger and paler than A. t. tristis (adult male averaging, wing, 74.93; tail, 

 50.29) . (Rocky Mountain district of United States. ) 



Astragalinns tristis pallidus (p. Ill) 

 dd. Smaller and darker than A. t. trislis (adult male averaging, wing, 70.10; 

 tail, 44.45). (Pacific coast district of the United States.) 



Astragalinns tristis salicamans (p. 112) 

 66. Under tail coverts yellow; upper tail-coverts black or clive-green; inner webs 

 of exterior rectrices with basal or middle portion white or else without any 

 white, 

 c. Inner webs of exterior rectrices partly white. 

 d. Pileum glossy black; inner webs of exterior rectrices white to near tips. 

 e. Back, scapulars, and auricular region olive-green. (Rocky Mountains to 



California. ) Astragalinns psaltria psaltria, adult male (p. 114) 



ee. Back, scapulars, and auricular region glossy black or partly so. 

 /. Back, scapulars, and auricular region mixed black and olive-green (in 

 varying relative proportion ) . ( Southwestern border of United States 

 and northern Mexico, occasionally to California and Colorado. ) 



Astragalinns psaltria arizonse, adult male (p. 115) 

 ff. Back, scapulars, and auricular region uniform glossy black. 



g. Under parts pale yellow (canary yellow or between canary yellow 

 and citron yellow) ; wing and tail longer, averaging 64.77 and 41.15, 

 respectively. (Mexico in general, and southern Texas.) 



Astragalinns psaltria mexioanns, adult male (p. 117) 



gg. Under parts bright yellow (lemon yellow) ; whig and tail shorter, 



averaging not more than 62 48 and 38.10, respectively. 



h. Larger, with under wing-coverts mostly blackish and with more 



black on flanks; wing averaging 62.48; tail, 38.10; exposed cul- 



men, 9.91; depth of bill at base, 7.62; tarsus, 12.70. (State of 



Chiapas, southern Mexico, to Panama. ) 



Astragalinns psaltria crocens, adult male (p. 118) 



^ A few of the South American species of Spinus have the bill essentially like that 

 of AstragaUnus, but the style of coloration is always different and diagnostic of the 

 group. 



