712 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



brown, the ground color deepening into pale to light brown beneath 

 and in front of eyes and iato deep brown or chestnut-brown imme- 

 diately above eyes; facial circle or rim (very distiact) nearly uniform 

 brownish black; under parts dull white (the feathers buffy beneath 

 surface), marked with conspicuous mesial streaks of black and nar- 

 row irregular bars of black or dusky brown, producing a very regular 

 "herring-bone" pattern over the whole of the lower surface, except 

 anal region and median portion of lower abdomen, which are immacu- 

 late pale buff or buffy white; legs pale brownish buff to dull buffy 

 whitish, barred, more or less heavily, with brown; bill pale dull yel- 

 lowish (in dried skins), the latero-basal portion grayish or horn color, 

 pea greenish ia life; iris light yellow; toes brownish (ia dried skins). 

 Young. — Eemiges and rectrices (if developed) as in adults; upper 

 parts mixed dull white and dull buff or clay-color narrowly and regu- 

 larly barred with dusky, the under parts similar but the bars lighter 

 or more brownish; a black facial (post-auricular) border, as in adults. 



Rufous phase. 



Adult female.'^ — ^Above bright russet or cinnamon-rufous, with 

 narrow mesial streaks of black, these broadest on crown, obsolete on 

 hindneck and rump; lower hindneck and upper back indistinctly 

 spotted with pale buff, each feather having two or three pairs of 

 roundish or, sometimes, transverse spots; occiput or upper nape 

 with large, partly concealed, blotches of pale buff, forming an incon- 

 spicuous interrupted band; outer webs of exterior scapulars mostly 

 white, tipped or terminally mai^iaed with black; outer webs of outer- 

 most middle and greater wing-coverts also with a lai^e subterminal 

 spot of white; outer webs of primaries broadly banded with cinna- 

 mon and dull ochraceous-buff, the spots of the former color becoming 

 dusky next to shaft, and the paler ones iaclining to white exteriorly 

 on proximal half of the second to sixth quills (counting from outside), 

 inclusive; tail banded with cimiamon-brown and light rusty cinna- 

 mon, the bands of the former color decidedly the broader (especially 

 on middle rectrices) and margined, as well as more or less mottled, 

 with dusky; face buffy whitish strongly tinged with rusty, especially 

 around eyes, the auricular region terminated by a broad bar (facial 



= Described from bo. 44818, coll. Am. Mus. Nat. Hist., from Bahia, Brazil, this 

 being the only example I have seen of the extreme rufous phase, which is very excep- 

 tional in South America and does not occur at all in the considerable series of speci- 

 mens examined from Panama and Costa Rica. 



The rufous phase of 0. choliba ia much paler than that of either 0. vermiculatus or 

 0. guatemalse, has the face whitish, instead of rufous, and bordered posteriorly by a 

 conspicuous postauricular bar of black, and the markings on the under parts are very 

 different, having a distinct and regular "herring-bone" pattern, as in the grayish 

 brown phase. 



