BIRDS OF NORTH AND MIDDLE AMERICA. 235 



KEY TO THE SPECIES ATJD SUBSPECIES OF ME6AQUISCALUS. 



a. Plumage glossy purplish black or dark steel blue, becoming violet anteriorly, 

 more greenish on wings and tail (sometimes on posterior parts of body also). 

 (Adult males. ) 

 b. Bill larger and stouter (culmen not less than 36.1, depth of bill at base not less 

 than 12.7); plumage more highly glossed, the gloss violet only on head and 

 neck, or on head, neck, and anterior portions of body. {MegaquiscaZus 

 major. ) 

 c. Tail much shorter than wing; violet color of anterior portions confined to 

 head, neck, and chest (wing averaging 182.4, tail 171). (South Atlantic 

 and Gulf coasts of United States. ) 



Megaqniscalas major major, adult male (p. 236) 



CO. Tail not much shorter than wing, sometimes longer; violet color of anterior 



portions extending at least to upper back and upper breast. 



d. Tail averaging longer than wing; breast and anterior portion of sides 



violet. 



e. Larger, with proportionally longer and more slender bill (wing averaging 



189, tail 217.2, culmen 44.7, depth of bill at base 14.7). (Southern 



Texas and through eastern Mexico and Central America to northern 



Colombia. ) Megaquiscalns major maoroums, adult male (p. 238) 



ee. Smaller, with proportionally shorter and thicker bill (wing averaging 

 180, tail 188, culmen 41.7, depth of bill at base 14.7). (Coast of south- 

 western Mexico, from State of Guerrero to Territory of Tepic.) 



Megaquiscalus major obscurns, adult male (p. 241) 

 dd. Tail averaging shorter than wing; breast and sides mostly steel blue. 

 e. Larger, with shorter and stouter bill (wing averaging 165.9, tail 163.6, 

 culmen 38.6, depth of bill at base 12. 9). (Coast of western Mexico in 



state of Sinaloa.) Megaquiscalus major graysoni, adult male (p. 241) 



ee. Smaller, with longer and more slender bill (wing averaging 164.6, tail 

 161, culmen 39.6, depth of bill at base 12.9). (Coast of northwestern 

 Mexico, in State of Sonora. ) 



Megaquiscalus major nelsoni, adult male (p. 242) 



66. Bill smaller and more slender (culmen not more than 34.3, depth of bill at base 



not more than 10.2) ; plumage with a duller gloss of violet extending over 



entire under parts, back, and rump. 



V. Wing more than 165, tail 177.8 or more; bill much more slender terminally, 



with tip very slightly decurved; inner webs of primaries not conspicuously 



widened. (Valley of Mexico. ) 



Megaquiscalus tenuirostris, adult male (p. 243) 

 cc. Wing 127; tail not more than 139.7; bill but slightly tapering terminally, 

 with tip strongly decurved; inner webs of primaries conspicuously widened 

 beyond middle. (Interior of Nicaragua. ) 



Megaquiscalus nicaraguensis, adult male (p. 244) 

 (la. Plumage mainly dusky brown above, paler brown, tawny, buffy, or whitish 

 below. (Adult females.) 

 6. Larger (wing more than 127, tail more than 114); under parts brown (grayish 

 brown, buffy brown, cinnamon-brown, etc.). 

 c. Pileum, hindneck, and upper back grayish brown, not conspicuously differ- 

 ent from color of rump; bill distinctly decurved at tip. 

 d. Larger, with relatively longer tail (wing averaging more than 143.5, tail 

 averaging more than 137.2); under parts darker, more grayish brown. 



