598 Annals of the Carnegie Museum. 



h. More or less of a chestnut-brown patch on sides of neck. 

 i. Brown on sides of neck confined to the postocular region, 

 scarcely visible from below. 



Formicarius umbrosus, $ , 9 • 

 ii. Brown patch passing around on front of throat, almost 

 meeting on jugulum, forming an interrupted jugular 

 collar; lower parts dull grayish-olive. 



Formicarius hoffmanni, $ , 9 . 



hh. No brown on sides of neck; whole head, neck, and chest 



black, breast fading into sooty-slate on abdomen and 



flanks. Formicarius nigricapillus, $ , 9 • 



f. Throat slate-color or else black, spotted with white. 



g. Chest concolorous with abdomen or bright brown, not slaty; 

 throat slate-color. 

 h. Lower parts dark seal-brown; whole pileum and nape slaty- 

 black (Carribean lowlands). Myrmeciza exsul, 9« 

 hh. Lower parts rich ruddy-brown, only fore part of pileum 

 slaty-black; (Pacific lowlands). 



Myrmeciza occidentalis, 9 • 

 gg. Chest dark slate-color; throat black, spotted with white; 

 flanks and back dark, rich brown. 



Myrmeciza Icemosticta, 9 • 



dd. Under tail-coverts variously colored, but not uniformly brown or 



chestnut. 



e. Back bright chestnut-brown, wing-coverts and tertials broadly 



tipped with cinnamon-buff or brown. 



/. Throat black; breast white, heavily spotted with black; flanks 



ashy. Hylophylax ncevioides, $ . 



ff. Throat whitish; spots on chest olive-brown; flanks grayish-olive. 



Hylophylax ncevioides, 9 • 

 ee. Back not bright chestnut-brown. 



/. Whole throat and median portion of chest and breast pure white; 

 upper parts dark seal-brown. 



Gymnopithys bicolor olivascens, $ , 9 • 

 ff. Throat and breast not white (immaculate). 



g. Throat or chest or both, streaked or mottled with white and 

 black or dusky; never uniformly colored. 

 h. Sides of head and neck cinnamon-buff. 

 i. Bill long and slender (longer than tarsus); throat indis- 

 tinctly mixed with white and blackish; rest of lower 

 parts bright buffy. Rhamphoccenus rufiventris, $ , 9 • 

 ii. Bill shorter than tarsus; centre of throat whitish, sur- 

 rounded by black; breast ashy; flanks dull grayish-brown. 

 Rhamphoccenus semitorquatus, $ , 9 • 

 hh. Sides of head and neck not cinnamon-buffy. 



*. Middle and greater wing-coverts prominently tipped with 

 buff-ochraceus or white. 



