CAS BTTLLETIN Tk), UNITED STATES NATIONAL MUSEUM. 



and under parts white, the latter tinged with gra}- (especiall} on sides 

 of neck and breast), becoming pale brownish on flanks. 



Nidification. — Unknown . 



Range. — Southern Mexico (including Yucatan) and adjacent parts 

 of Guatemala. (Monotypic.) 



KEY TO TITE Sl'BSPECIES OF NANNORCHILUS LEUCOGASTER. 



a. Tail indistinctly barred; under tail-coverts pale brown, spotted, not barred with 

 darker brown, or else the bars grayish brown, not ])lackish. 

 h. Paler and more rufescent, the upper parts isabella color to brownish cinnamon. 



(Southwestern Mexico.) Nannorchilus leucogaster pacificus ({). 619) 



hit. Darker, the upper jjarts deep russet-brown. (Chiapas and Tabasco to eastern 



Guatemala.) Nannorchilus leucogaster musicus (p. 620) 



Intermediate in color between h and h\i. (Southern Tamauliiias to Oaxaca. ) 



Nannorchilus leucogaster leucogaster (p. 61 .S) 



aa. Tail distinctly barred with dusky; under tail-coverts whitish Itarred with dusky. 



(Yucatan and Campeche. ) Nannorchilus leucogaster brachyurus (p. 620) 



NANNORCHILUS LEUCOGASTER LEUCOGASTER (Gould). 

 GOULDS WREN. 



Adults in spring and^ suiwrner. — Above plain bufly grayish brown 

 (between broccoli brown and dark isabella color), the rectrices and 

 secondaries narrowly and very indistinctly barred with darker; outer- 

 most primaries edged with pale l>utiy gi'a}" or grayish bufl'y; a broad 

 and conspicuous superciliary stripe of white; a rather broad postocu- 

 lar streak of brown, involving more or less of upper portion of auric- 

 ular region; suborbital and auricular regions (except upper margin of 

 latter) grayish white, the feathers very narrowly and rather indistinctly 

 margined or edged with grayish brown; malar region, chin, throat, 

 chest, breast, and abdomen grayish white, the throat and abdomen 

 nearly pure white, the chest (especially laterally) faintly shaded with 

 pale gra}^; sides and flanks pale bufly brown or isabella color; under 

 tail-coverts similar but paler, tipped with whitish or very pale grayish 

 buffy, and marked with a subterminal spot or bar of deeper isabella 

 color; axillars and under wing-coverts dull white, tinged with grayish 

 bufly; inner webs of remiges edged (not sharply) with pale dull bufl'y; 

 maxilla horn color, with paler tomia; mandible pale brownish or dull 

 pale yellowish (in dried skins); legs and feet pale horn color (in dried 

 skins). 



Adults in autumn and vyinter. — Similar to the spring and summer 

 plumage, but color of upper parts decidedly browner (cinnamon-brown 

 or between russet and raw-umber). 



Young. — Similar in coloration to adults, but flanks much paler (dull 

 bufly whitish or very pale brownish i>ufly), and under tail-coverts 

 inunaculate pale bufl'y brown or isabella color. 



