BIRDS OF NORTH ANB MIDDLE AMERICA. 183 



CfiKstrus guatimozinus Oassin, Proc. Ac. Nat. Sci. Phila., 1867, 71, part (Turbo, n. 

 Colombia). 



Gymnostinops guatimozinus Sclatee, Cat. Birds Brit. Mus., xi, 1886, 314 (Reme- 

 dies).— Salvin and GoDMAN, Biol. Centr.-Am., Aves, i, 1886, 439, pi. 32. — 

 Robinson, Flying Trip to Tropics, 1895, 160 ( lower Magdalena R. , Colombia) . 



Genus OSTINOPS Cabanis. 



Ostinops^ Cabanis, Mus. Hein., i, Sept., 1851, 187. (Type, Oriolus cristatus 

 Gmelin, =Xanthomus decumanus Pallas. ) 



Very large arboreal Icteridse with bill longer than head, straight, 

 acute elongate-conical, with basal outline of mandibular rami nearly 

 vertical, truncate, the basal portion of culmen elevated and expanded, 

 forming a narrow but prominent frontal shield; head completely 

 feathered. 



Bill slightly longer than head, elongate-conical, acute, compressed, 

 with nearly straight outlines, its basal depth decidedly less than dis- 

 tance from nostril to tip of maxilla, its basal width nearly half that 

 measurement; culmen straight, slightly decurved terminally, the basal 

 portion slightly elevated, arched, and expanded, forming a narrow 

 frontal shield, the rounded posterior extremity of which is about on 

 line with anterior angle of eye; gonys straight, decidedly more than 

 half as long as culmen but shoi"ter than distance from nostril to tip of 

 maxilla; commissure straight to behind nostril, where decidedly 

 deflexed to the rictus; mandibular rami posteriorly widened and 

 truncate, but not swollen. Nostril much below lateral median line of 

 maxilla, small, broadly oval or nearly circular, bored directly into the 

 horny rhinotheca, slightly beveled anteriorly, posteriorly touching 

 the loral feathering. Wing long (more than four times as long as 

 culmen), the tip long (much longer than culmen) and wedge-shaped; 

 ninth (outermost) primary intermediate between fifth and fourth; 

 seventh or sixth primary longest; four outer primaries gradually con- 

 tracted terminally and pointed, their inner web faintly sinuated. 

 Tail between three-fourths and four-fifths as long as wing, graduated, 

 with middle pair of rectrices shorter than third pair and differently 

 colored from the others, the rectrices rather narrow but not contracted 

 terminally. Tarsus longer than maxilla from nostril, very stout, its 

 anterior scutella very distinct; middle toe, with claw, decidedly 

 shorter than tarsus (about equal to maxilla from nostril); outer toe 

 with claw reaching slightly beyond base of middle claw, the inner 

 slightly shorter; hallux nearly as long as inner toe, much stouter, its 

 claw decidedly shorter than the digit. Head completely feathered, a 

 sparse crest of narrow elongated feathers springing from middle of 

 crown. 



Coloration. — Black and chestnut, or olive-green, olive-brown, or 

 russet, with the tail mostly yellow. 



1" oiTirod, knocheru, und Sip, mTto6, -q Gesicht, Antlitz." 



