BIRDS OF NORTH AND MIDDLE AMERICA. 181 
KEY TO THE SUBSPECIES OF PREMNOPLEX BRUNNESCENS. 
a. Throat more rufescent; general color darker, with black margins to feathers of 
under parts broader. 
b. Throat paler (ochraceous to tawny-ochraceous). (Central to northwestern 
Colombia.)...........- Premnoplex brunnescens brunnescens (extralimital.)¢ 
bb. Throat darker (deep tawny-ochraceous to rufous-tawny.) (Santa Marta dis- 
trict of Colombia.).......- Premnoplex brunnescens coloratus (extralimital).6 
aa. Throat paler (buff to ochraceous-buff); general color paler, with black margin to 
feathers of under parts narrower. (Costa Rica and Panamé.) 
Premnoplex brunnescens brunneicauda (p. 181). 
PREMNOPLEX BRUNNESCENS BRUNNEICAUDA (Lawrence). 
COSTA RICAN PREMNOPLEX. 
Adults (sexes alike).—Pileum olive or deep grayish olive, the 
feathers margined with dusky, those of the forehead with rather 
broad mesial streaks of buff; rest of upper parts mummy brown 
passing into vandyke brown on rump and upper tail-coverts, the 
scapulars and interscapulars indistinctly margined with dusky, the 
latter (especially on upper back) sometimes with narrow and mostly 
indistinct shaft-streaks of buff; tail darker or duller vandyke brown 
than rump, sometimes nearly seal brown; loral, superciliary, and 
supra-auricular regions buff, the latter streaked with dusky; auricu- 
lar and ‘suborbital regions dusky or dark sooty brown, streaked (the 
latter spotted or flecked) with buffy; malar region, chin, and throat 
deep buff, the feathers of throat usually indistinctly margined with 
blackish; rest of under parts olive, conspicuously variegated with 
large spots and streaks of light buff and black or dusky margins to 
the feathers, the former largest on chest, where occupying all of each 
feather except a broad black margin, narrower, more streak-like on 
sides, more indistinct on abdomen and flanks, indistinct or obsolete 
on under tail-coverts; maxilla black, mandible dull whitish or yellow- 
ish (Gn dried skins) with a sharply defined stripe of blackish along 
tomia; iris brown; legs and feet dusky or horn color (in dried 
skins). 
Young.—Similar to adults in coloration but under parts of body 
with margins to feathers rather broader and more blackish and 
mesial spots and streaks rather deeper buff. 
« Margarornis brunnescens Sclater, Proc. Zool. Soc. Lond., June 16, 1856, 27, pl. 
116 (Bogoté, Colombia; coll. P. L. Sclater); Cat. Birds Brit. Mus., xv, 1890, 123, 
part.—Premnoplex brunnescens brunnescens Bangs, Proc. Biol. Soc. Wash., xxi, July 
27, 1908, 159 (centr. and w. Colombia to Peru; crit.). 
b Premnoplex coloratus Bangs, Proc. New Engl. Zool. Club, iii, Mar. 31, 1902, 84 
(San Miguel, Santa Marta, Colombia, 7,500 ft.; coll. E. A. and O. Bangs).—Premno- 
plex brunnescens coloratus Bangs, Proc. Biol. Soc. Wash., xxi, July 27, 1908, 159 
(Sierra Nevada de Santa Marta; crit.). 
