122 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
Adult (sex not determined).—Length (skin), 173.5; wing, 93; tail, 
55; culmen, 22; tarsus, 31; middle toe, 20. 
Yucatan (Tizimin). 
Furnarius pallidus Lawrence, Ann. N. Y. Acad. Sci., ii, no. 9, May 29, 1882, 
288 (Yucatan; coll. G. N. Lawrence). 
Formicarius pallidus Lawrence, Ann. N. Y. Acad. Sci., ii, no. 9, 1882 (index).— 
Boucarp, Proc. Zool. Soc. Lond., 1883, 450 (Tizimin, Yucatan; crit.).— 
ReicHenow and ScHatow, Journ. ftir Orn., 1884, 388 (reprint of orig. 
descr.).—Ripeway, Proc. U. 8. Nat. Mus., xvi, 1893, 684 (monogr.). 
[Formicarius] pallidus SHarPe, Hand-list, iii, 1901, 39. 
Flormicarius] m[oniliger] pallidus Ripeway, Proc. Biol. Soc. Wash., xxi, Oct. 20, 
1908, 194, in text. 
[Myrmornis] pallidus Heine and ReicHENow, Nomencl. Mus. Hein. Orn., 1890, 
124. 
Formicarius montliger (not of Sclater, 1856) ScuatErR, Cat. Birds Brit. Mus., xv, 
1890, 308, part (Tizimin, Yucatan).—Satvin and Gopman, Biol. Centr.-Am., 
Aves, ii, 1892, 233, part (Tizimin). 
FORMICARIUS MONILIGER UMBROSUS (Ridgway). 
NICARAGUAN ANTTHRUSH. 
_ Similar to F. m. moniliger but without any chestnut across foreneck, 
the black of throat giving way, more or less abruptly, on chest to dull 
slate color or sooty gray; under tail-coverts darker, more castaneous, 
brown; terminal portion of auricular region, together with supra- 
auricular region (sides of occiput) and sides of neck, varying from 
chestnut to vinaceous-cinnamon. 
Young.—Much like adults but malar region, chin, and throat dull 
whitish or buffy, transversely mottled or barred with dusky, or else 
uniform dull sooty blackish; whitish abdominal area transversely 
spotted or clouded with grayish dusky. 
Adult male——Length (skins), 158-180 (164); wing, 86-93 (90.2); 
tail, 49.5-57 (53.7); culmen, 19-23.5 (21.4); tarsus, 31-36 (33.5); 
middle toe, 18-20.5 (19.1).% 
Adult female—Length (skins), 146-170 (161); wing, 86-91.5 
(88.3); tail, 48-55 (51.7); culmen, 19-22 (20.3); tarsus, 31.5-33.5 
(32.3); middle toe, 17.5-20 (18.8).° 
@ Fourteen specimens. b Twelve specimens. 
Locality. Wing. | Tail. | CU | rarsus,| Middle 
MALES. 
Ten adult males from eastern Costa Rica...........-...2...2-.- 90. 6 54. 4 20.9 33.9 19.2 
Four adult males from Nicaragua................0..202-2- 22 ee 89 52.1 22.5 32. 6. 18.9 
FEMALES. 
Ten adult females from eastern Costa Rica..........-.---.----- 88 ” 61.4 20.1 29 18.7 
Two adult females from Nicaragua..................-.222.222-- 89.7 53 21.3 32.3 19.3 
