630 



BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



rior portion of sides; flanks more or less tinged with brown; maxilla 

 horn color or duskj^ brown, with paler tomia; mandible pale (lilaceous 

 or pale pinkish gray in life;" iris brown;" legs and feet light horn 

 color. 



Young. — Similar to adults in coloration of upper parts, but under 

 parts dull white medially, yjale rusty brown laterally, without dusky 

 bars or bands, but the lower throat indistinctly streaked or flecked 

 with dusky, the chest mottled with the same; superciliarj^ stripe much 

 less distinct than in adults. 



Adult mafe.— Length (skins), 130-154 (141); wing, 63-69.5 (66.1); 

 tail, 49-58.5 (53.9); exposed culmen, 17-19 (17.8); tarsus, 20.5-24 

 (22.2); middle toe, 12-15 (13.9).* 



Adult feynale.—hengih (skins), 125-144 (184); wing, 59.5-65.5 

 (61.3); tail, 46.5-54.5 (48.9); exposed culmen, 16-18 (16.7); tarsus, 

 20.5-22.5 (21.6); middle toe, 12-15 (13.7). '^ 



Southeastern Mexico, in States of Guerrero (Apiluluca;*^ Kio Balsas'*), 

 Oaxaca (Chimalapa; Tapana; Santa Efigenia; Guichicovi; San Juan 

 del Rio), and Chiapas; Guatemala (Vera Paz) ? ; Salvador (Conchagua) ?; 

 Honduras ? 



Thryothorus pleurostictus Sclatee, Ibis, ii, Jan., 1860, 30 ("Vera Paz," Guatemala; 

 coll. P. L. Sclater); Cat. Am. Birds, 1862, 21, pi. 4; Proc. Zool. Soc. Lond., 

 1870, 551, part (Mexico; Guatemala). — Lawrence, Bull. IT. S. Nat. Mus., 

 no. 4, 1876, 13 (Tapana, Guichicovi, and Santa Efigenia, Oaxaca; habits; 

 descr. eggs) . 



[Thryothm-us'] pleurostktus Baied, Review Am. Birds, 1864, 121 (diagnosis). 



aSumichrast. 

 i Nineteen specimens. 

 " Fourteen specimens. 



Specimens from different geographic areas compare in average measurements as 

 follows: 



Locality. 



MALES. 



Two adult males from interior of Guerrero. . 



Three adult males from coast of Guerrero 



Ten adult males from Oaxaca 



Four adult males from Chiapas 



FEMALES. 



Two adult females from interior of Guerrero 

 One adult females from coast of Guerrero . . . 



Eight adult females from Oaxaca 



Four adult females from Chiapas. .*. 



Middle 

 toe. 



13.7 

 13.5 

 13.7 

 U. 7 



13.5 

 14 

 13.2 

 15 



Specimens from the interior of Guerrero (Rio Balsas and Apiluluea) show a 

 decided approach in coloration toward T. p. nisorius. 



'^ Specimens from these two localities show a decided approach in coloration to 

 T. p. nisorius. 



