36 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



bb. Pileum partly white, 

 c. Pileum with more or less of white on basal portion of feathers. ( Thamnophilus 

 doliatus.) 

 d. Darker, with white bars of upper parts narrower and black bars of under 

 parts broader. 

 e. Wing averaging longer (75.5 in adult male),« tail relatively shorter (aver- 

 aging 63 in adult male). (Guianas; Venezuela?). 



Thamnophilus doliatus doliatus, adult male (extralimital).^ 

 ee. Wing averaging shorter (72.6 in adult male), tail relatively longer (aver- 

 aging 62.8 in adult male). (Atlantic slope of Mexico, except Yucatan 

 and Campeche, and Central America.) 



Thamnophilus doliatus mexicanus, adult male (p. 40). 



dd. Paler, with white bars of upper parts broader and black bars of imder parts 



narrower. 



e. Averaging smaller (wing averaging 70.1, tail 58.4), with black bars on 



under parts usually broader. (Pacific slope, from Chiapas to western 



Panama.) Thamnophilus doliatus pacificus, adult male (p. 43). 



ee. Averaging larger (wing averaging 72, tail 63.2), with black bars on under 

 parts usually narrower. (Yucatan and Campeche.) 



Thamnophilus doliatus jnicatanensis, adult male (p. 44). 

 cc. Pileum spotted or barred with Avhite. (Eastern Panama and Colombia.) 



Thamnophilus multistriatus, adult male (p. 45). 

 aa. Plumage largely rufescent (back, wings, etc., plain chestnut or tawny). 



b. Under parts dull slate-gray streaked with whitish. {Thamnophilus virgatus.) 

 c. Wings and tail clearer chestnut-tawny (more rufescent); white streaks on 

 pileum broader, those on under parts extended over greater part of abdomen. 



(Northwestern Colombia.) Thamnophilus virgatus virgatus (p. 46). 



cc. Wings and tail duller chestnut- tawny (more cinnamomeous); white streaks 

 on pileum narrower, those on under parts also narrower and on abdomen 

 confined to median line. (Central Colombia.) 



Thamnophilus virgatus nigriceps (extralimital).c 

 hh. Under parts buffy or tawny (with or \vithout transverse bars). 

 c. Under parts distinctly barred with blackish. 



Thamnophilus multistriatus, adult female (p. 45). 

 cc. Under parts not distinctly if at all barred. 



Thamnophilus radiatus and subspecies, adult female.*^ 

 Thamnophilus doliatus and subspecies, adult female. <^ 



« No females of this form have been examined by me. 



^[Lanius] doliatus Linnaeus, Syst. Nat., ed. 12, i, 1766, 138 (South America; based 

 on Lanius cayanensis striatus Brisson, Orn., ii, 187; etc.). — Thamnophilus doliatus 

 Vieillot, Nouv. Diet. d'Hist. Nat., iii, 1816, 315 (Cayenne); Sclater, Cat. Birds Brit. 

 Mus., XV, 1890, 207, part. — L[anius] {ferrugineus) (not of Gmelin, 1788) Richard and 

 Bernard, Actes de la Soc. d'Hist. Nat. Paris, i, pt. i, 1792, 116 (Cayenne). — Lanius 

 (ferruginatus) Reich (G. C), Mag. des Thierreicha, i, Abth. 3, 1795, 129 (emendation 

 of L. ferrugineus Richard and Bernard). — Lanius rubiginosus Bechstein, Allgem. 

 iJbers. de Vogel, i, 1793, 696 (new name for L. ferrugineus Richard and Bernard); 

 Latham, Index Orn., Suppl., 1801, p. xix. 



c Thamnophilus nigriceps Sclater, Proc. Zool. Soc. Lond., 1868, 571 (Bogota, 

 Colombia; coll. P. L. Sclater); Cat. Birds Brit. Mus., xv, 1890, 194, pi. 12. 



d The differences between adult females of the several forms of these two species are 

 not sufficiently definite to be intelligibly expressed in a key — at least not without 

 expenditure of much more time than I am able to give the subject. 



