BIRDS OF NORTH AND MIDDLE AMERICA. 3 



d. Outermost primary much longer than third, usually equal to or longer than 

 fourth; if wing less than 71.1 the outermost primary equal to fifth. 

 e. Exposed culmen decidedly shorter than middle toe without claw. 

 /. Tarsus decidedly longer than middle toe with claw, more than one-third 



as long as tail Calospiza ( p. 34 ) 



ff. Tarsus not decidedly, if at all, longer than middle toe with claw, not 

 more than one-third as long as tail. 

 >j. Head unicolored (blue, gray, or olive); maxillary tomium nearly 



straight Tanagra (p. 54) 



gg. Head conspicuously striped w ith black and white; ' maxillary tomium 



concave anteriorly, convex posteriorly Spindalis (p. 62) 



ee. Exposed culmen not shorter than middle toe without claw. 

 /. Bill stouter, more or less tumid basally; maxillary tomium with a more 

 or less distinct median tooth, or else plumage unicolored (red in 

 adult males, yellowish in females and young) ; adult males with more 



or less of red Piranga (p. 75) 



//'. Bill more slender, compressed, the culmen .sharply ridged; maxillary 



tomium without trace of median tooth, and plumage parti-colored; 



adult males without any red (except sometimes a supra-auricular 



stripe). 



g. Larger (wing more than 76.2); bill deeper (depth at base nearly half 



exposed culmen); outermost (ninth) primary shorter than fifth; 



under parts black or gray, with white axillary patcli. 



Heterospingus (p. lOo) 

 gg. Smaller (wing less than 76.2) ; bill shallower (depth at base decidedly 

 less than half exposed culmen ) ; outermost (ninth ) primary longer 

 than fifth; under parts yellow or partly yellow. 



Hemithraupis (p. 105) 

 dd. Outermost (ninth) primary little, if any, longer than third, or else {Tachy- 

 phonas, part ) wing less than 71.1, and outermost primary shorter than fifth. 

 e. Loral and frontal feathers stiff, erect, dense, plush-like. 

 /. Mandibular rami enlarged and swollen, longer than gonys; sexes differ- 

 ent in color (adult males black and red or black and yellow, adult 



females much duller) Ramphocelus (p. 107) 



//'. Mandibular rami not unusually developed, shorter than gonys; sexes 



alike in color (black and red) Phlogothraupis (p. 120) 



ee. Loral and frontal feathers normal. 

 /. Maxilla strongly hooked at tip, its tomium with a conspicuous median 



"tooth" Lanio (p. 122) 



//'. Maxilla not strongly hooked at tip, its tomium without a conspicuous 

 (if any) "tooth." 

 g. Bill larger, the exposed culmen two-thirds, or more, as long as tarsus. 

 h. Bill more slender (depth of maxilla immediately in front of nos- 

 trils less than one-third the distance from nostril to tip). 

 i. Tail even, shorter than distance from bend of wing to tips of 

 secondaries; ninth primary longer than third; color olive-green 

 above, gray or gray and white below; head bhu-k and white; 



sexes alike in color Phaenicophilus (p. 126) 



ii. Tail rounded, equal to or longer than distance from bend of wing 

 to tips of secondaries; ninth primary shorter than third; adult 

 males black, usually with white on wing coverts (sometimes 

 with red, yellow, etc., on pileum); adult females rufous 

 brownish, olive, or yellowish Tachyphonus (p. 129) 



' Except in females and young. 



