^0 BULKETIN 60, UNITED STATES NATIONAL MUSEUM. 



[Rarnphocxnus] semitorquatus Sclater and Salvin, Nom. Av. Neotr., 1873, 73. 



Rhavrphocxnus semitorquatus Sclater, Ibis, 1883, 96 (Veragua, Panama; Antio- 

 quia, Colombia; crit.); Cat. Birds Brit. Mus., xv, 1890, 262 (Veragua; 

 Antioquia). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 219 

 (La Balsa, Rio Sucio, and San Carlos, Costa Rica; Santiago de Veragua, 

 Calovevora, and Lion Hill, Panama; Colombia). — Bangs, Proc. New Engl. 

 Zool. Club, iii, 1902, 42 (Volcan de Chiriqui, Panama, 1,000-2,000 ft.).— 

 Carriker, Ann. Carnegie Mus., vi, 1910, 612 (Caribbean lowlands to 1,500 

 ft., Costa Rica; habits). 



[Rhamphocxnus] semitorquatus Sharpe, Hand-list, iii, 1901, 28. 



{?)Rhamphocsenus dnereiveniris (not of Sclater?) Sclater and Salvtx, Proc. 

 Zool. Soc. Lond., 1879, 525 (Antioquia, Colombia; crit.). 



Genus CERCOMACRA Sclater. 



Cercomacra Sclater, Proc. Zool. Soc. Lond., 1858, 244. (Type, Myrmothera 

 cserulescens Vieillot.) 



Medium-sized Formioariidae (length about 120-135 mm.) with 10 

 rectrices, distinct rictal bristles, and color plain gray or blackish 

 with concealed white dorsal patch and narrow wliite tips to wing- 

 coverts (sometimes with broad white tips to lateral rectrices), the 

 adult female of some species brown above, tawny or ochraceous 

 below. 



Bill shorter than head, moderately stout, rather broad and de- 

 pressed basally, its width at frontal antias much greater than its 

 depth at same point and equal to at least half the distance from 

 nostril to tip of maxilla; culmen distinctly ridged, straight basally, 

 gently decurved for about terminal half, the tip of maxilla distinctly 

 but not conspicuously uncinate; maxillary tomium nearly straight, 

 minutely notched subterminally ; mandibular tomium nearly straight, 

 minuteh^ (very indistinctly) notched subterminally; gonys faintly 

 convex (more decidedly so basally), moderately ascending terminally. 

 Nostril exposed, posteriorly in contact with feathering of latero- 

 frontal antiae, small, broadly oval, margined above and posteriorly 

 by very narrow membrane, with an internal tubercle showing within 

 posterior portion. Rictal bristles distinct; feathers of chin and 

 malar apex with distinct terminal setfe. Wing moderate, with 

 longest primaries distinctly longer than secondaries; sixth, fifth and 

 fourth, or fourth and fifth primaries longest, the tenth (outermost) 

 one-half to nearly three-fifths as long as the longest, the eighth 

 about as long as secondaries. Tail as long as wing or a little shorter, 

 graduated (graduation about equal to length of tarsus), the rectrices 

 (10) broad, rounded terminally. Tarsus much longer than whole 

 culmen (a little more than one-third as long as wing), slender, the 

 acrotarsium rather distinctly scutellate, the planta tarsi completely 

 fused; middle toe, with claw, much shorter than tarsus (about as 

 long as exposed culmen) ; outer toe, without claw, reaching to 

 beyond middle of subterminal phalanx of middle toe, the inner toe 



