86 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



Medium-sized Cuculinse (length about 345-395 mm.) with rela- 

 tively very small, conspicuously crested, head ; slender, nearly straight, 

 bill; long, strongly graduated tail with very broad rectrices, and with 

 feathers of rump and upper tail-coverts greatly elongated, the longest 

 of the latter reaching to tip of tail. 



Bill relatively small, slender and weak, very little decurved ter- 

 minally, its depth at anterior end of nostrils decidedly less than at 

 base of gonys, not greater than its width at same point, and equal to 

 less than one-third the distance from nostril to tip of maxilla; exposed 

 culmen shorter than middle toe without claw, straight or even slightly 

 depressed basally, gently decurved terminally, rather narrowly 

 rounded; gonys about as long as mandibular rami, straight, slightly 

 ascending terminally, prominent basally from narrowing of the rami; 

 maxillary tomium gently concave anterior to nostril, faintly convex 

 beneath nostrils, without trace of subterminal notch. Nostril linear, 

 longitudinal, along lower side of nasal fossa, overhung by a distinct 

 operculum. Wing rather long and pointed, the longest primaries 

 exceeding secondaries by combined length of tarsus and basal pha- 

 lanx of middle toe, or by more than one-fourth the length of wing; 

 fifth and sixth primaries longest, the fourth and seventh decidedly 

 shorter and about equal, the eighth slightly longer than third, the 

 ninth about equal to first, the tenth (outermost) less than half as long 

 as the longest — the three outer primaries strongly bowed or incurved. 

 Tail about one-fourth longer than wing, graduated for nearly half 

 its length, the rectrices extremely broad (width of lateral ones equal 

 to distance from point of bill to anterior angle of eye) . Tarsus more 

 than one and a half times as long as middle toe without claw, nearly 

 one-fourth as long as wing, slender. 



Plumage and coloration. — Orbital region naked immediately in 

 front of and behind eye, feathered above and below; eyelashes incon- 

 spicuous; no trace of bristles about base of bill; a conspicuous, 

 pointed, erectile occipital crest; plumage of under parts full, soft, 

 blended; feathers of back, etc., distinctly outlined, those of rump, 

 together with upper tail-coverts very long, rather narrow, with edges 

 semi-decomposed, the longer coverts reaching to tip of tail. Color 

 dusky above, with pale margins to feathers, these broader and more 

 whitish on wing-coverts; rump, upper tail-coverts, and tail more 

 grayish; rectrices (except middle pair) tipped with white, dusky sub- 

 terminally; underparts of body plain white; a broad white post- 

 ocular streak and beneath this a dusky brown auricular streak. 



Range. — Southeastern Mexico to Cayenne, southern Brazil, Bolivia, 

 and Paraguay. (Two species.) 



This is perhaps the most distinct of any of the American genera of 

 the Cuculinse, and it is difficult to determine its nearest relative. In 

 the slender and nearly straight bill, small head, thin neck and large 



