372 BtrLLETIN 50, TJNITED STATES NATIONAL MUSEUM. 



ee. Tail moderately rounded, the lateral rectrices three-fourths as long as 

 middle pair; wing more pointed, the longest primaries decidedly 

 longer than secondaries; bill less depressed, its depth at nostrils equal to 

 decidedly more than half the distance from nostril to tip of maxilla, the 

 gonys more convex, more strongly ascending terminally. 



Nystactes (extralimital).o 



dd. Bill relatively shorter, its width at rictus equal to length of gonys; bristly 



antrorse feathers round base of bill less strongly developed; side of head 



unicolored (tawny); general color of upper parts tawny, narrowly barred, 



including tail, with black; under parts of body neither barred nor spotted. 



Bucco (extralimital).6 



56. Bill compressed, its width at nostrils much less than its depth at same point. 



c. Tip of maxilla strongly bifid (cleft medially); bristly antrorse feathers round 



base of bill longer; longest primaries decidedly longer than secondaries; 



general color of upper parts grayish brown, indistinctly spotted with grayish 



white; a black pectoral band (sometimes a jugular band also); tail plain 



grayish brown ; bill wholly black Hypnelus (p. 380) . 



cc. Tip of maxilla not distinctly if at all bifid ; bristly antrorse feathers round base 



of bill shorter; longest primaries only slightly longer than secondaries; upper 



parts distinctly spotted with brown, tawny, or bufiy on dusky ground; tail 



barred; bill red, orange, or horn color. 



d. Bill shorter, the culmen from base much less than half as long as wing, less 



compressed, its width at nostrils equal to about one-third the length of 



exposed culmen Ecchaunomis (p. 384). 



dd. Bill longer, the culmen (from base) nearly half as long as wing, more com- 

 pressed, its width at nostrils equal to about one-fourth the length of 



exposed culmen Nystalus (extralunital).": 



aa. Bill weaker, more gradually decurved terminally, with tip of maxilla not uncinate, 



the gonys more or less decurved terminally. (Malacoptilinss.) 



b. Tenth (outermost) primary at least half as long as ninth, the fifth to seventh 



longest; tail much more than half as long as wing; bill decinved only terminally. 



c. Feathers of anterior portion of malar region elongated and pointed, forming a 



conspicuous tuft on each side of chin ; tail more strongly rounded or graduated, 



the lateral rectrices not more than three-fourths as long as middle pair 



(usually much less); coloration varied (usually more or less streaked or 



spotted). 



d. Tail relatively longer, less strongly graduated, unicolored; under parts not 



white, striped with black Malacoptila (p. 387). 



a Nystactes Gloger, in Eroriep's Notizen, xvi, 1827, 277. (Type, Biuxo tamatia 

 Gmelin.) — Nyctactes (emendation) Gray, List Gen. Birds, 1840, 10. — Chaunornis Gray. 

 List Gen. Birds, 1841, 13. (Type, Bucco tamatia Gmelin.) 



Amazon Valley to Guiana. (Two species ?) 



6 Bucco Brisson, Om., iv, 1760, 92. (Type, Bujxo capensis Linn8eus=5. collam 

 Latham.) (See Newton, Ibis, 1876, 94r-l0i.)—Eutamatia Fitzinger, Sitz. k. Akad. Wiss. 

 Wien (Math.-nat. Classe), xxi, heft 2, 1856, 298. (Type, Bum) capensis Linnaeus.) 



Amazon Valley to Guiana. (Monotypic.) 



Nystalus Cabanis and Heine, Mus. Hein., iv, heft 1, Jan. 15, 1863, 139. (Type, 

 Alcedomaculata Gmelin.) ("Von viamXoc {=vuax&Krric, schlafrig) entnehmen, sind." 

 (Cabanis and Heine.) 



Brazil to Bolivia and Paraguay. (Two species.) 



