164 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
reaching to beyond middle of subterminal phalanx of middle toe, 
the inner toe conspicuously shorter, reaching (without claw) only to 
subterminal articulation of middle toe; hallux longer than inner but 
shorter than outer toe; claws moderate in size and curvature to 
rather large and strongly curved, much compressed, that of the 
hallux shorter than the digit. 
Coloration.—Plain brownish, the rump and upper tail-coverts 
usually more rufescent, sometimes bright or deep chestnut; under 
parts paler than upper, the throat sometimes gray or whitish or 
squamated. Sexes alike. 
Nidification—Nest (of S. umbretta) composed of leaf-ribs placed 
in a rounded chamber at the end of a gallery in the ground. Eggs 
white.¢ 
Range.—Southern Mexico to Cayenne, Argentina, and Peru. 
(About twelve species.) 
KEY TO THE SPECIES AND SUBSPECIES OF SCLERURUS. 
a. Lower rump and upper tail-coverts chestnut, distinctly different from color of 
back. 
6. Chin and throat whitish or grayish, distinctly different from color of chest. 
.¢. Chin and throat dull white or grayish white, the feathers margined or tipped 
with dusky. (Southern Brazil.)........ Sclerurus umbretta (extralimital).> 
cc. Chin dull white deepening into gray on throat, the feathers without distinct, 
if any, darker margin or tip. 
d. Back, etc., brown; chest tawny brown or dull rusty. (Sclerurus albigularis.) 
e. Back, etc., olive-brown; chest tawny brown; throat grayish white, deep- 
ening into pale gray on lower portion. (Venezuela; Tobago.) 
Sclerurus albigularis albigularis (extralimital).¢ 
ee. Back, etc., burnt-umber brown; chest dull rusty; throat smoke gray. 
(Northeastern Colombia.) 
Sclerurus albigularis propinquus (extralimital).¢ 
@ Goeldi, Ibis, 1896, 305. 
b M{yiothera] wmbretta Lichtenstein, Verz. Doubl., 1823, 43 (Bahia, Brazil).— 
Myioturdus umbretta Ménétriés, Mem. de 1l’Acad. St. Petersb., ser. 6, Sci. Nat., i, 
1835, 468 (Bahia).—Flormicarius] wmbretta Gray, Gen. Birds, i, 1840, 211.—Sclerurus 
umbretta Sclater and Salvin, Proc. Zool. Soc. Lond., 1867, 574 (lower Amazon Valley); 
Burmeister, Syst. Ueb. Th. Bras., ili, 1856, 45; Ridgway, Proc. U. 8. Nat. Mus., xii, 
1890, 22 (monogr.); Sclater, Cat. Birds Brit. Mus., xv, 1890, 114.—Sclerurus cenudat- 
cutus umbretta Hellmayr, Novit. Zool., xiv, 1907, 56 (crit.).—Ozypyga scansor Méné- 
triés, Mém. de l’Acad. St. Petersb., ser. 6, Sci. Nat., i, 1835, 520, pl. 11 (Rio de 
Janeiro, Brazil).—T[inactor] fuscus Maximilian, Beitr. Naturg. Bras., iii, 1831, 1106, 
part (female only). 
¢ Sclerurus albigularis ‘‘Sw[ainson] Braz. B. t. 78” Bonaparte, Consp. Av., i, 1850, 
210 (nomen nudum); Sclater and Salvin, Proc. Zool. Soc. Lond., 1868, (pub. April, 
1869), 630 (Venezuela; diagnosis); Sclater, Cat. Birds Brit. Mus., xv, 1890, 114, 
part (excl. syn. S. canigularis).—Sclerurus albogularis Ridgway, Proc. U. 8. Nat. 
Mus., xii, 1889 (1890), 24 (monogr.; Venezuela; Tobago). 
4 Sclerurus albigularis propinquus Bangs, Proc. Biol. Soc. Wash., xiii, Nov. 11, 1899, 
99 (Chirua, Santa Marta, Colombia, 7,000 ft.; coll. E. A. and O. Bangs). 
