752 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
dd. Lateral rectrices more extensively white (the basal black on outermost 
pair restricted to a small area entirely concealed by under tail-coverts). 
(Panamé to western Ecuador.) 
Trogon strigilatus chionurus, adult male (p. 754). 
bb. Pileum and chest ‘‘dead” slate-black or slate color, without trace of metallic 
gloss (except, sometimes, very faintly, on occiput and hindneck). 
ce. Outermost pair of rectrices with much less than terminal third white. (Trogon 
melanocephalus.) 
d. Head, neck, and chest slate-black to blackish slate. (Eastern Mexico 
to northeastern Costa Rica.) 
Trogon melanocephalus melanocephalus, adult male (p. 756). 
dd. Head, neck, and chest slate color to slate-gray. (Pacific coast district 
of Costa Rica and Nicaragua.) 
Trogon melanocephalus illztabilis, adult male (p. 759). 
cc. Outermost pair of rectrices with terminal half, or more, white. (Western 
Mexico.) 
Trogon citreolus, adult male (p. 759). 
aa. Back, scapulars, rump, upper tail-coverts, and middle rectrices blackish slate to 
slate-gray, like head, neck, and chest. (Adult females.) 
b. Wing-coverts and secondaries narrowly barred with white or pale gray; lateral 
rectrices barred with white. 
ce. Posterior under ae reddish orange or orange-red. 
Trogon bairdii, adult female (p. 753). 
ce. Posterior under parts orange-yellow. (Trogon strigilatus.) 
d. Lateral rectrices with white much less extended. 
Trogon strigilatus strigilatus, adult female (extralimital). 
dd. Lateral rectrices with much more white. 
Trogon strigilatus chionurus, adult female (p. 755). 
bb. Wing-coverts and secondaries plain blackish slate or slate color; lateral rectrices 
not distinctly (if at all) barred with white. 
c. White tip to lateral rectrices much shorter, with anterior outline more directly 
transverse. (Trogon melanocephalus.) 
d. Head, neck, and chest darker (slate-blackish). 
Trogon melanocephalus melanocephalus, adult female (p. 757). 
dd. Head, neck, and chest more grayish (slate color to slate-gray). 
Trogon melanocephalus illetabilis, adult female (p. 759). 
cc. Whitetip tolateral rectrices much longer, with lateral outlinesstrongly oblique. 
Trogon citreolus, adult female (p. 760). 
TROGON BAIRDII Lawrence. 
BAIRD'S TROGON. 
Similar to T. strigilatus chionurus, but posterior under parts bright 
orange or orange-red instead of orange-yellow. 
Adult male.—Pileum and hindneck black, usually more or less 
glossed. with violet-blue; back, scapulars, anterior lesser wing-coverts, 
Anim. in Menag., pt. iii, Jan. 1, 1838, 332 (Brazil; coll. W. Swainson); Gould, Mon. 
Trog., ed. 1, 1838, pls. 10, 11, and text.— A[ganus] venustus Cabanis and Heine, Mus. 
Hein., iv, Feb., 1863, 194 (Colombia; coll. Heine Mus.).—T[rogon] cyanurus Finsch, 
Proc. Zool. Bae. Lond., Nov., 1870, 559, in text (Cayenne; coll. Bremen Mus.; ex 
Hartlaub, manuscript). 
Like many other of the South American Trogons, this species unquestionably 
requires subdivision. The specimens from southeastern Brazil, for example, are 
very different from those from Cayenne, etc. 
