66B BULLETIN 50, UNITED STATES NATIONAL M0SE0M. 



slightly shorter than outer; hallux (without claw) slightly shorter 

 than outer toe (without claw), its claw decidedly shorter than the digit; 

 basal phalanx of middle toe adherent to outer toe for greater part 

 (sometimes nearly all) of its length, to inner toe for about two-thirds 

 of its length. 



Coloration. — Above brown, usually barred or squamated with dusky, 

 the remiges and rectrices uniform dusky; sometimes a white bar across 

 greater wing-coverts; under parts grayish, becoming brown on sides, 

 flanks, and posterior parts, more or less barred or squamated (espe- 

 cially on lateral and posterior portions) with dusky. 



Range. — Southern Mexico to Gruiana and eastern Ecuador. 



KEY TO THE SPECIES OF MICEOCERCULnS.<2 



a. Back and gcapulars plain brown, without dusky margins to the feathers. (Adults. ) 

 y. Ground color of chest and breast brownish gray or grayish brown. 

 u. Brownish gray of breast, etc., uniform, or with extremely faint brownish 



bars. (Isthmus of Panama.) Microcercnlus luscinia, adults (p. 669) 



cc. Brownish gray of breast, etc. , not uniform, but varied with dusky or dusky 

 and whitish. 

 d. Brownish gray of breast with V-shaped marks of dusky; flanks darker 

 brown, uniform. (Eastern Costa Rica.) 



MiorooeroTiliis daulias, adults (p. 668) 

 dd. Grayish brown of breast with V-shaped and irregular marks of white and 

 dusky; flanks lighter brown, faintly barred with dusky. (Coast of Ven- 

 ezuela.) Microcercnlus pectoralis, adults (extralimital ) & 



hh. Ground color of chest and breast white (barred with dark grayish brown). 

 (Province of Santa Marta, northeast Colombia.) 



Microcercnlus corrasus, adults (extralimital)<! 

 aa. Back and scapulars marked with crescentic bars, or terminal margins, of dusky. 

 (Young.) 

 6. Chin and throat brownish gray, not very different from rest of under parts. 



(Guatemala.) MicroceTculns philomela, young^^ (p. 667) 



hh. Chin and throat dull white, 

 c. Throat spotted with brown; median portion of chest and breast pale buffy 

 grayish, conspicuously marked with spots and crescentic bars of dusky. 



Microceroulus daulias, young (p. 668) 



cc. Throat immaculate dull white; whole chest and breast nearly uniform 



brownish gray Microcercnlus luscinia, young (p. 670) 



"Including two allied extralimital species. 



i Microcercnlus pectoralis Richmond [in Robinson and Richmond] Proc. U. S. Nat. 

 Mus., xxiv, no. 1247, Oct. 3, 1901, 178 (La Guaira, Venezuela; coll. U. S. Nat. Mus.) 



<^ Microcercnlus marginatus {not Beterocnemis marginatus Sdnter) Bangs, Proc. Biol. 

 Soc. Wash., xiii, 1899, 107 (Chirua, Santa Marta, Colombia) ; Allen, Bull. Am. Mus. 

 N. H., xiii, 1900, 180 (Onaca, Santa Marta). — Microcerculus corrasus Bangs, Proc. New 

 Engl. Zool. Club, iii, Mar. 31, 1902, 87 (Chirua, Santa Marta, Colombia, 7,000 ft. alt.; 

 coll. E. A. and O. Bangs). 



This form is closely allied to Microcerculus sguamulatus Sclater and Salvin (Proc. 

 Zool. Soc. Lond., 1875, 37, pi. 6), of northwestern Venezuela, and may possibly be 

 the same. 



''I have not seen the adult of this species, which appears to be undescribed, and 

 hence can not include it in the key. 



