BIRDS OF NORTH AND MIDDLE AMERICA. 313 



belonging to one leading type, of which the toothed bill is the most 

 prominent feature. The same may be said of Barhatula and Smi- 

 lorhis, and Megalsema and Cyanops." (Shelley, Cat. Birds Brit. 

 Mus., Vol. XIX, p. 13.) 



The authors of a beautiful monograph of the family, Messrs. 

 C. H. T. and G. F. L. Marshall, have divided the Capitonidse into 

 three subfamilies, Pogonorhynchinse, Megalaeminae, and Capitonin£e, 

 but later writers ignore these subdivisions. 



KEY TO THE AMERIQAN GENERA OP CAPITONID^. 



a. Tomia smooth, without distinct, if any, subterminal notch or denticulation; tip of 

 mandible simple (normal) ; bill more slender, its width at base less than length 

 of maxilla from nostril; mesorhinium broadly rounded or flattened; tail very little 

 more (often less) than two-thirds as long as wing, the outermost pair of rectrices 

 two-thirds to more than three-fourths as long as middle pair; adult males without 

 a nuchal tuft; sexes distinctly different in coloration. 

 b. Bill more slender; nostrils narrower, separated by a much narrower mesorhinium; 

 tail more than two-thirds as long as wing, the outer pair of rectrices much less 

 than three-fourths as long as middle pair; outermost (tenth) primary about 

 half as long as ninth, relatively broad; back, etc., plain green; sexes with col- 

 oration of head and neck very different Eubucco (p. 314). 



bb. Bill stouter; nostrils circular, separated by a much broader mesorhinium; tail 

 less than two-thirds as long as wing, the outer pair of rectricesnearly tomore 

 than three-fourths as long as middle pair; outermost (tenth) primary much less 

 than half as long as ninth, relatively very narrow; back, etc., black, streaked, 

 etc., with yellow or orange (or both), or plain glossy blue-black; sexes with 

 coloration of head not essentially different (except, sometimes, throat). 



Capito (p. 319). 



an. Maxillary tomium conspicuously notched and toothed subterminally; tip of 



mandible bifurcate; bill stouter, its width at base greater than length of maxilla 



from nostril; mesorhinium narrowly ridged; tail much more than two-thirds as 



long as wing, the outer pair of rectrices less than two-thirds as long as middle 



pair; adult males with a nuchal tuft of elongated, glossy black feathers, the sexes 



otherwise alike in coloration. 



b. Lateral base of maxilla more swollen; mesorhinium less distinctly ridged; middle 



toe, without claw, much more than two-thirds as long as tarsus; outermost 



rectrices slightly more than half as long as middle pair; coloration much more 



varied, the chest bright red, pileum glossy black with a white spot on each 



side of occiput Semnornis (extralimital)." 



bb. Lateral base of maxilla less swollen; mesorhinium more distinctly ridged; mid- 

 dle toe, without claw, not more than two-thirds as long as tarsus; outermost 

 rectrices nearly two-thirds as long as middle pair; coloration plain, without 

 red, glossy black (except nuchal tuft of adult male), or white. 



Dicrorhynchus (p. 324). 



« Tetragonops (not of Gerstacker, February or March, 1855) Jardine, Edinburgh 

 Philos. Journ., n. s., ii, no. 2, October, 1855, 404 (type, T. ramphastinus Jardine).^ 

 Pan (not of Oken, 1816) Richmond, Auk, xvi, January, 1899, 77 (to replace Tetra- 

 gonops J andine, preoccupied). — Semnornis Richmond, Auk, xvii, April, 1900,179 (to 

 replace Pan Richmond, preoccupied). 



A monotypic genus, the single known species of which is confined to eastern 

 Ecuador. 



