260 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



j. Larger (wing averaging 107.2); back more broadly streaked or 

 spotted with black (the black sometimes prevailing) ; orange 

 color less intense, never (?) inclining to scarlet on head. 

 (State of Oaxaca, southern Mexico, to Nicaragua.) 



Icterus sclateri, adult male (p. 297) 



jj. Smaller (wing averaging 100.8) ; back more narrowly streaked 



with black; orange color more intense, frequently inclining 



to scarlet on head.' (Southern plateau and Pacific coast 



district of Mexico. ) Icterus pustulatus, adult male (p. 295) 



ii. Back very sparsely and narrowly, or not at all, streaked with black. 

 j. Larger (wing more than 100, exposed culmen more than 24); 

 middle wing-coverts pale yellow; general color yellow, never 

 orange. (Tres Marias islands, n. w. Mexico. ) 



Icterus grayaouii, adult male (p. 298) 

 jj. Smaller (wing less than 95, exposed culmen less than 20); 

 middle wing-coverts white; general color rich orange, rarely 

 orange-yellow. (Yucatan.) 



Icterus auratus, adult male (p. 299) 

 hh. Middle wing-coverts bright lemon-yellow, like lesser coverts; con- 

 cealed bases of greater coverts black. {Icterus xantkornus.) 

 i. Bill much shorter (culmen of male not more than 25.4, averaging 

 22.3). (Caribbean coast district of Colombia, Venezuela, and 

 Guiana; Trinidad; Isthmus of Panama?.) 



Icterus xanthornus xanthornus, adult male and female (p. 300) 

 ii. Bill much longer (culmen 25.9-27.9, averaging 26.9). (Island 

 of Curagao, Caribbean Sea. ) 



Icterus xanthornus curasoensis, adult male and female (p. 303) 

 gg. Outer webs of greater wing-coverts entirely white. 

 h. Pileum, hindneck, back, and rump yellowish olive-green. (Island 

 of Jamaica, Greater Antilles. ) 



Icterus leucopteryx, adult male and female (p. 303) 

 hh. Pileum, hindneck, and rump yellowish. 

 i. Yellow of pileum, etc., very slightly, if at all, tinged with olive. 

 (Island of Grand Cayman, Greater Antilles.) 



Icterus bairdi, adult male and female (p. 304) 

 ii. Yellow of pileum, etc., strongly tinged with olive. Island of St. 

 Andrews, Caribbean Sea. ) 



Icterus lawrencii, adult male and female (p. 305) 

 66. Tail distinctly bicolored (black and yellow or black and orange, in sharply 

 contrasted areas), 

 c. Pileum and hindneck yellow. (Icterus mesomelas. ) 

 d. Longer innermost secondaries conspicuously edged with white; smaller 

 (wing averaging 90.4 in male, 86.6 in female). (Southeastern Mexico to 

 Honduras. ) . .Icterus mesomelas mesomelas, adult male and female (p. 305) 

 dd. Longer innermost secondaries without any white edgings; larger (wing 

 averaging 96.3 in male, 92.7 in female). (Nicaragua to Colombia.) 



Icterus mesomelas salvinii, adult male and female (p. 307) 

 cc. Pileum (except, sometimes, forehead) and hindneck black. 

 d. Breast black; exposed culmen 20.8-24.6. (Mexican plateau and adjacent 

 portions of southwestern United States; Lower California.) 



Icterus parisorum, adult male (p. 308) 

 dd. Breast orange or yellow; exposed culmen less than 20.8. 



' Earely, however, the color decidedly yeHpw., 



