Nciu Birds from NortJiwcMern Mexico. 29 



Distrilmtiini.— Coast lowlands of western Mexico from Miizathin nt least 

 to sonthern border of the Territory of Tepic. 



f:>Hhi<p('clfic chumders. — Similar to Arremonops superciliosa siimichmiili, l)iit 

 the median line of crown and sides of head more ashy ; foreback dis- 

 tinctly shaded with ashy and rest of back clearer and less olive <;reeii ; 

 nnder i)arts paler and less bnffy. Median and superciliary crown streaks 

 darker ashy than in typical superciliosa, the rufous lateral stripes paler; 

 chin and throat much paler and less buffy— about as in SLimichrasti ; 

 back a little grayer. 



Dimensions of type.— ^Yu•^g 66; tail 56 ; culmenlS; tarsus 20.5. 



General notes.— By a slip of the pen in the 'Auk' for April, 1898, p. 157, 

 I placed A. sumichrasti as a subspecies of ritfivirgata. In fact it is a sub- 

 species of the quite distinct .-J. superciliosa, which (with all its subspecies) 

 belongs to the west coast of Central America and Mexico. .1. rufirirgata 

 and its subspecies belong to the east coast. 



Basileuterus rufifrons caudatus subsp. nov. Sonora Warbler. 



Type No. 164260, cP ad., U. S. Nat. Mus., Biological Survey Collection, 

 from vicinity of Alamos, Sonora, Mexico. Collected January 8, 1899, by 

 E. A. Goldman. 



Distribution.— Southwestern Sonora and northern Sinaloa, Mexico. 



Subspecific characters.— 't^mn\'M- to Basileuterus rufifrovsjouyi from which 

 it differs in the paler and more restricted rufous area on crown; ratlier 

 paler gray of back ; more fulvous color on crissum combined with shorter 

 wing and longer tail and tarsus. 



Dimensions of type.— Wing 51 ; tail 60 ; culmen 10 ; tarsus 2;]. Type of 

 B. r. jouyi. —W\ng 52 ; tail 56 ; culmen 9 ; tarsus 20. 



Thryothoius felix pallidus subsp. nov. Mazatlan Wren. 



7///»f No. 164270, $ ad., U. S. Nat. Mus., Biological Survey Collection, 

 from Chacala, Durango, Mexico. Collected February 27, 1899, by E. A. 

 Goldman. 



Distrihutioii.— Arid tropical region of western Mexico, from northern 

 Sinaloa and western Durango to southwestern Puebla and northern 

 Guerrero, Mexico. 



Snhspecific characters.— Generidly similar to typical T. felix, but slightly 

 smallei-, with upper parts less rufous and more olive brown ; tail paler 

 brown, with nuich more distinct black bars ; under parts paler, and under 

 tail coverts barred with dingy whitish and l)lack instead of rufous browni 

 and black. 



Dimensions of type. — Wing 56 ; tail 53; culmen 14; tarsus 21. 



General notes. — Thryotltorus felix was described from southwestern 

 Oaxaca. We have a winter specimen taken at Ometepec, Guerrero, so near 

 the type locality both in distance and climatic conditions that I am safe 

 in considering it typical, and have used it as such in the foregoing com- 

 parison. Numerous specimens from Tepic, Sinaloa, and western Durango 

 agree with the type of Thryotluirus f. pallidus. 



