580 BULLETIN 5 0, UNITED STATES NATIONAL MUSEUM 



its northern limit in Veragua, while another (Daptrius americanus) 

 extends no farther northward than Guatemala and Honduras. The 

 remaining two extend northward only to the limits of the subtropical 

 country, or to about latitude 30°; Polyborns cheriway is more or less 

 abundant along the southern border of the United States, from 

 southern California to Florida, as well as throughout Middle America, 

 thence southward, and also on the islands of Socorro and Tres Marias, 

 off the western coast of Mexico, and in Cuba; P. lutosns is restricted 

 to the Guadalupe Islands, off the coast of Baja California, between 

 latitudes 28°45' and 29°10' N. In South America the range of the 

 group is much more extensive, every portion of the continent, even to 

 its extreme southern limits, being inhabited by one or more of the 

 species. 



Genus DAPTRIUS Vieillot 



Ibyder Vieillot, Analyse, 1816, 22. (Type, "Petit aigle de I'Amerique, Buff."= 



Falco americanus Boddaert). 

 Ibtder (emendation) Katjp, Mus. Senckenburg, iii, Heft 3, 1845, 262. 

 Daptrius Vieillot, Analyse, 1816, 22. (Type, by special designation, D. ater 



Vieillot (Analyse, p. 68).) 

 Gymnops Spix, Avium Species Novae (Av. Bras.), i, 1824, 11. (Type, G. fasctatus 



Spix = Daptrius ater Vieillot.) 



Arboreal, mostly frugivorous and insectivorous, Polyborinae with 

 tarsus scarcely if at all longer than middle toe with claw; outer toe 

 very much longer than inner toe, which is but little longer than hallux; 

 inner webs of primaries very shallowly sinuated, and prevailing color 

 uniform glossy black, the naked skin of face and throat, and the legs 

 and feet, bright red in life. 



Bill much as in Milvago, but cere relatively much larger, its length 

 on top equal to more than one-third (sometimes equal to one-half) 

 the chord of culmen, the lower portion of its anterior outline less 

 receding; nostril small, nearly circular, with obvious, but not con- 

 spicuous central tubercle. Remiges (22) unusually developed but 

 primaries (10) much longer than secondaries, the fourth or fifth 

 (from outside) longest, the fii*st (outermost) intermediate between 

 eighth and tenth, the outer five with inner webs shallowly sinuated. 

 Tail long and broad (about two-thirds as long as wing), much rounded, 

 the rectrices (10) broad, with rounded tips. Tarsus about as long 

 as middle toe with claw, covered with very irregularly hexagonal 

 scales, then somewhat larger on acrotarsium, especially on lower 

 portion; outer toe very much longer than inner toe, the hallux about 

 three-fourths as long as the latter; web between basal portion of outer 

 and middle toes well developed; claws normal, rather long and acute. 



Plumage and coloration. — Plumage in general compact and lustrous, 

 but soft and downy on posterior underparts, full but more loose-webbed 

 on head, the loral and orbital regions, more or less of malar region, 



