BIRDS OF NORTH AND MIDDLE AMERICA. 739 



rump, upper tail-coverts, and basal half of tail buff. Similar also to 

 EwMypis, but tarsus relatively longer (at least one-third as long as 

 wing), ninth primary shorter than fourth (instead of longer), and 

 without white on rectrices. 



Bill decidedly shorter than head, sometimes scarcely more than half 

 as long, but very variable as to relative length and width and extent of 

 depression (sometimes the width at nostrils equal to, usually decidedly 

 less than, length of exposed culmen); culmen rather distinctly ridged, 

 nearly straight for basal third or more, becoming gradually more decid- 

 edly curved terminally, the tip of the maxilla moderately produced, but 

 scarceh' uncinate; gonys very faintly convex; maxillary tomium nearly 

 straight to near tip, where faintly concave, with distinct subterminal 

 notch. Nostril longitudinal, nearly linear, in lower anterior portion 

 of nasal fossse, overhung by a broad membraneous operculum. Rictal 

 bristles very distinct, but variable as to development, usually extending 

 but little if any beyond nostrils (when directed forward), sometimes 

 reaching considerably beyond. Wing rather short to rather long, more 

 or less rounded (eighth to fifth, seventh, seventh and sixth, or sixth and 

 fifth primaries longest, ninth shorter than fifth, usually shorter than 

 second, sometimes shorter than first) ; wing-tip variable, always shorter 

 than middle toe with claw, sometimes much shorter than middle toe 

 without claw. Tail more or less shorter than wing, or at least not 

 longer (except in B. rufifrons)^ usually equal to or longer than distance 

 from bend of wing to tips of secondaries, more or less rounded (some- 

 times almost even), the rectrices usually rather narrow, with tips sub- 

 acuminate. Tarsus one-third to much more than one-third as long as 

 wing, rather stout, its scutella fairly distinct; middle toe, with claw, 

 much shorter than tarsus, its basal phalanx united for more than half 

 its length to outer toe, for about half (more or less) its length to 

 inner toe. 



Coloration. — No white on rectrices; wings unicolored; pileum three - 

 striped (two black lateral stripes, inclosing a median one of chestnut, 

 rufous, rufous-orange, 3'ellowish, or grayish), or else wholly chestnut- 

 rufous or (if unicolored and concolor with the back) the lower rump, 

 upper tail-coverts, and basal half of tail buff orochraoeous-buff; upper 

 parts (except as described) plain olive, olive-green, or grayish; under 

 parts yellowish (with or without whitish or grayish throat), yellow 

 anteriorly and whitish posteriorly, or whitish or buffy medially and 

 grayish or olive laterally. 



Nidification. — Unknown. 



Hcmge.— The whole of continental Tropical America. (Numerous 

 species, mostly South American.) 



The thirty -odd species which compose this group as characterized 

 above (and as usually recognized) vary so much in the details of 

 external structure that were it not for certain species of intermediate 



