BIRDS OF NORTH AND MIDDLE AMERICA. 797 



berculate; bill broader basally and more depressed; nostril sur- 

 rounded by membrane ; bristles of frontal antise, rictus, and chin less 

 developed. 



Bill small (less than half as long as head), depressed, and triangular, 

 its width at frontal antiai about equal to distance from nostril to tip 

 of maxilla and about twice its depth at same point; gonys about as 

 long as mandibular rami. Nostril rather large, longitudinally oval, 

 surrounded by membrane, this about equally wide in front, above, 

 and below. Rictal bristles anil bristly tips of latero-frontal plumules 

 and those of chin moderately developed. Wing rather long and 

 pointed, the primaries exceeding secondaries by about the length of 

 tarsus; ninth and eighth primaries longest, the seventh but little 

 shorter, the outermost (tenth) nearly as long as sixth. Tail about as 

 long as distance from bend of wing to tip of secondaries or slightly 

 shorter, faintly emarginate. Tarsus moderately long (about two- 

 ninths as long as wing), slender, its scutellation ultra-pycnaspidean, 

 the planta tarsi, except on extreme upper portion, covered with 

 numerous small, approximately diamond- or lozenge-shaped scutella, 

 which become gradually more distinct on the lower portion where 

 roughened and subtuberculate, the scutella of the acrotarsium with 

 lower margins elevated, especially on lower part of tarsus, where the 

 scutella are more irregular, more or less reduced in size, and rough- 

 ened; middle toe, with claw, decidedly shorter than tarsus, its basal 

 phalanx united to outer toe for much the greater part of its length, to 

 inner toe for about half its length; outer toe (without claw) reaching 

 to middle of subterminal phalanx of middle toe, the inner toe decidedly 

 shorter; hallux about as long as outer toe, but much stouter, its claw 

 decidedly shorter than the digit; all the claws rather strongly curved 

 and sharp, much compressed. Head without crest. 



Coloration. — Pileum plain slate color; back, etc., plain olive-green; 

 wings dusky, with olive-yellowish edgings and crossed by two bands 

 of pale olive-yellow or yellowish white; under parts pale yellowish, 

 tinged with olive on chest and passing into white on throat; a white 

 superciliary streak. 



Nidificatio n . — (Unkno \\' n . ) 



Range. — Costa Rica. (Monotypic'O 



IDIOTRICCUS ZELEDONI (Lawrence). 

 ZELDON'S TYF.ANNULET. 



Adult male. — Pileum and hindneck plain slate color, the former 

 margined below by a white superciliar}' streak, broadest anteriorly 

 where involving greater part of loral region; an indistinct spot of 

 dusky grayish immediately in front of eye on lower posterior portion 

 of loral region; a rather broad postocular streak of slate color, con- 

 fluent with color of hindneck; suborbital region and lower portion of 



