(Cobán, Guatemala; Belize); Proc. Zool. Soc. Lond., 1870, 837 (San Pedro, Honduras). — Salvin and Sclater, Ibis, 1860, 36 (Yzabál, Guatemala). — Salvin, Proc. Zool. Soc. Lond., 1867, 145 (Santa Fé de Verágua, w. Panamá); 1870, 195 (Mina de Chorcрa and Bugaba, w. Panamá). — Lawrence, Ann. Lyc. N. Y., ix, 1868, 109 (Angostura, Costa Rica). — Frantzius, Journ. für Orn., 1869, 305 (Costa Rica). — Boucard, Proc. Zool. Soc. Lond., 1878, 61 (San Carlos, Costa Rica); Ann. Soc. Linn. Lyon, 1878, 39 (Guatemala). — Nutting, Proc. U. S. Nat. Mus., vi, 1883, 386 (Sucuyá, Nicaragua), 405 (Los Sábalos, Nicaragua). — Zeledón, Anal. Mus. Nac. Costa Rica, i, 1887, 115 (Pacuare, Jiménez, and Pozo Azúl, Costa Rica). — Salvin and Godman, Biol. Centr.-Am., Aves, ii, 1892, 214, part (Playa Vicente and Sochiapa, Vera Cruz; Belize, Brit. Honduras; Chiséc, etc., Guatemala; San Pedro, Honduras; Matagalpa, etc., Nicaragua; Tucurríqui, etc., Costa Rica; Bugaba, Mina de Chorcha, and Santa Fé de Verágua, Panamá). — Richmond, Proc. U. S. Nat. Mus., xvi, 1893, 501 (Rio Escondido, Nicaragua; habits). — Cherrie, Expl. Zool. Merid. Costa Rica, 1893, 42 (Lagarto, Boruca, Térraba, and Buenos Aires, s. w. Costa Rica). — Underwood, Ibis, 1896, 440 (Volcan de Miravalles, Costa Rica).
- [Cercomacra] tyrannina Sclater and Salvin, Nom. Av. Neotr., 1873, 73, part. — Sharpe, Hand-list, iii, 1901, 28, part.
- Cercomacra tyrannina tyrannina Carriker, Ann. Carnegie Mus., v, no. 1, Oct. 1, 1908, 9, in text (s. w. Costa Rica).
- Cercomacra crepera Bangs, Auk, xviii, Oct., 1901, 365 (Divala, Chiriquí, Panamá; coll. E. A. and 0. Bangs). — Dearborn, Pub. 125, Field Mus. Nat. Hist., 1907, 109 (Los Amates, e. Guatemala; crit.).
- Cercomacra tyrannina crepera Bangs, Auk, xxiv, 1907, 296 (Boruca, Paso Reál, Pozo del Rio Grande, and Barranca, s. w. Costa Rica). — Carriker, Ann. Carnegie Mus., v, 1908, 8 (e. Costa Rica; crit.); vi, 1910, 612 (Costa Rica; crit.; habits). — Ferry, Pub. 146, Field Mus. N. H., orn. ser., i, no. 6, 1910, 271 (Guayabo, Costa Rica).
Genus GYMNOCICHLA Sclater.
- Gymnocichla Sclater, Proc. Zool. Soc. Lond., 1858, 274, (Type, Myiothera nudiceps Cassin.)
Medium-sized Formicariidæ (length about 140-160 mm.) resembling the larger and stouter species of Myrmeciza, but with bill weaker, less compressed anteriorly and less strongly uncinate, the culmen less distinctly ridged; nostril smaller; relatively shorter tarsus (only two-fifths as long as wing) , with acrotarsium distinctly scutellate; tail shorter (not more than four-fifths as long as wing), the adult males with loral and suborbital regions (sometimes whole pileum) naked.
Bill about as long as head, narrowly wedge-shaped in vertical profile (with nearly straight lateral outlines), its width at posterior end of nostrils about equal to its depth at same point and equal to a little less than half the distance from nostril to tip of maxilla; culmen slightly ridged, straight to near tip where abruptly decurved, the point of maxilla slightly or minutely uncinate; tomium straight, with
small subterminal notch, that of the mandible less distinct; gonys
