100 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
rusty or whitish; interscapulars extensively white basally; under 
parts plain deep tawny or rufous-tawny to nearly chestnut, the color 
deepest on chest, palest on abdomen, the flanks tinged with olive; 
maxilla blackish, becoming more horn colored terminally; mandible 
horn color, paler (sometimes whitish) terminally; iris brown; legs 
and feet horn color (bluish gray or grayish blue in life); length 
(skins), 148-152 (150); wing, 72-76 (73.6); tail, 53.5-57 (55.4); 
culmen, 19-20.5 (19.7); tarsus, 28-30 (29.2); middle toe, 18-19.5 
(18.8).¢ 
Eastern Panama (Loma del Leén; Panam4) and adjacent portion 
of northwestern Colombia (Rio Atrato). 
Myiothera nudiceps Casstn, Proc. Ac. Nat. Sci. Phila., 1850, 106, pl. 6 (Isthmus 
Panamé; coll. Acad. Nat. Sci. Phila.). 
Pyriglena nudiceps ScutatER, Proc. Zool. Soc. Lond., 1854, 118, part (Isthmus 
Panam4); 1857, 47, in text. 
Gymnocichla nudiceps SctatTER, Proc. Zool. Soc. Lond., 1858, 274 (monogr.); Cat. 
Birds Brit. Mus., xv, 1890, 272, part (Lion Hill; Panam4).—Lawrence, Ann. 
Lyc. N. Y., vii, 1862, 295 (Lion Hill; Panam4).—SciatTer and Satviy, Proc. 
Zool. Soc. Lond., 1864, 356 (Lion Hill, crit.; descr. female) —Satvin and 
Gopman, Biol. Centr.-Am., Aves, ii, 1892, 223; part (Lion Hill, Panamé).— 
Banes, Proc. New Engl. Zool. Club, ii, 1900, 24 (Lion Hill, Panama). 
[Gymnocichla] nudiceps SctaTER and Satvin, Nom. Av. Neotr., 1873, 73, part.— 
Suarre, Hand-list, iii, 1901, 32, part. 
Glymnocichla] nudiceps nudiceps Rrpaway, Proc. Biol. Soc. Wash., xxi, 1908, 194, 
in text. 
Pithys rufigularis (not of Sclater, ex Turdus rufigula Boddaert) Lawrence, Ann. 
Lyc. N. Y., vii, 1862, 293 (Lion Hill, Panam4; —adult female). 
Myrmeciza ferruginea LAwRENCcE, Ann. Lyc. Nat. Hist. N. Y., vii, 1862, 470 
(Lion Hill, Panam4; =adult female; see Sclater and Salvin, Proc. Zool. 
Soc. Lond., 1864, 356). 
Myrmelastes corvinus (not Thamnophilus corvinus Gould) Lawrence, Ibis, v, 
April, 1863, 182 (Lion Hill, Panam4 Railway; coll. G. N. Lawrence); Ann. 
Lyc. N. Y., viii, 1863, 485 (Lion Hill). 
Myrmelastes lawrencti, part, Sauvin and Gopman, Biol. Centr.-Am., Aves, ii, 
1892, 226, part (Lion Hill, Panam). 
a Six specimens. 
Locality. Wing. | Wait. ye | ter. | Maas 
MALES. 
Eight adult males from eastern Panama....................--- 76.1) 57.1} 20.5] 29.6 18.9 
Two adult males (G. w. erratilis?) from western Panama 
(Divala) sete acidsonsiccnesissesendaeacetotaaende so eeaceciemeees, besos 60.5 21.2 28.7 19 
Ten adult males (G. n. erratilis) from southwestern Costa Rica.| 78.9 61.7 20.9 30 19.4 
One adult male (G. ”. sanctx-martx) from Colombia......-.... 81 60.5 21.5 30 18.5 
FEMALES. 
Six adult females from eastern Panamé...............--......- 73.6| 55.4] 19.7] 29.2 18.8 
Ten adult females (G. n. erratilis) from southwestern Costa Rica.| 75.1 59.3 19.9 29.4 18.9 
One adult female (G. . sanctx-martz) from Colombia.......... 74 58 18.5 30.5 19.5 
