BIRDS OF NORTH AND MIDDLE AMERICA 69 



covered uniformly with rough or granular small hexagonal or quadrate 

 scales, only the terminal phalanges with transverse scutellae; claws 

 rounded beneath; wing very long and narrow, swallowlike, the outer- 

 most primary longest and none of the primaries sinuated on inner 

 web; tail ternlike, nearly as long as wing, forked for about half its 

 length, the lateral rectrices much attenuated; coloration, bluish gray 

 above, white beneath; size rather small. 



Genus ELANUS Savigny 



Elanus Savigny, Descr. figypte, Hist. Nat., i, 1809, 69, 97. (Type, by monotypy 



E. caesius S&vigny = Falco melanopterus Daudin.) 

 Aelanus (emendation) RiJppell, Neue Wirbelth., Vogel, 1839-40, 115. 

 Milans Boie, Isis, x, Heft 5, 1822, 549 (unintentional emendation of Milims). 



Medium-sized kitelilve hawks (wing about 270 to 342 mm.) with, 

 claws smooth and rounded underneath, tail much less than three- 

 fifths as long as wing, and adults with entire lower parts immaculate 

 white, the upperparts plain bluish gray with lesser wing coverts 

 black. 



Bill relatively small, compressed anteriorly but rapidly widening 

 from anterior margin of cere, its width at edge of frontal feathering 

 more than double that at anterior margin of cere ; cuhnen very nearly 

 as long as or sometimes a little longer than claw of hallux, regularly 

 and strongly decurved, the tip of maxilla (unguis) well produced; 

 gonys about one-third as long as cuhnen, faintly convex, not promi- 

 nent basally, very indistinctly if at all ridged; maxillary tomium 

 nearly straight; gape very wide and long, the rictus beneath middle 

 of eyes; cere strongly sinuated, very convex in front of nostril, reced- 

 ing and faintly concave below; nostril relatively large, longitudinally 

 oval or elliptical-oval. Wing very long and pointed, the longest 

 primary exceeding distal secondary by decidedly less, to a little more, 

 than half the length of wing; second primary or second and third 

 primaries longest, the first (outermost) equal to or longer than fourth; 

 one or two outer primaries with distal part of inner web shallowly 

 emarginated ; tips of longer primaries obtuse or rounded. Tail much 

 less, to decidedly more, than half as long as wing, its tip double-round 

 (the lateral rectrices sometimes longer, sometimes shorter than middle 

 pair). Tarsus as long as or slightly longer than middle toe with claw, 

 about as long as distance from tip of maxilla to middle of eye, rela- 

 tively stout, the upper half or more feathered in front and on sides, 

 elsewhere covered with minute roundish, rather indistinct scales, as 

 are also the first and second phalanges of the toes; outer and inner 

 toes equal in length or (sometimes) the outer slightly shorter than 

 the inner, extending to about middle of third phalanx of middle toe; 

 claws moderate in size and curvature, graduated in size (but that of 



