30 Nelson — New Birds from Northivestern Mexico. 



Heleodytes stridulus .s]>. nov. Brown-backed Wren. 



Type No. 164261, ? ad., U. S. Nat. Mas., Biological Survey Collection, 

 from Sierra de Choix, northeastern Sinaloa, Mexico. Collected October 

 16, 1S98, by E. A. Goldman. 



Distrihiawn.—kxi& mountain slopes of northeastern Sinaloa and adja- 

 cent parts of Sonora, Mexico. 



Description of type.— Crown blackish brown, darkest on forehead ; super- 

 ciliary stripe from bill to nape white, washed with fulvous ])rown ; loral 

 and postocular stripe blackish; cheeks from gape dingy whitish ; malar 

 stripe black ; sides of neck dingy whitish, streaked with dull blackish and 

 thinly washed with dull fulvous ; back and scapulars burnt umber brown, 

 marked witli irregular white shaft streaks and obscure blackish spots ; 

 upper tail coverts transversely baried with umber brown, black and 

 whitish ; outside of wings marked with spots of umber brown, black and 

 whitish; middle tail feathers ashy brown, indistinctly and narrowly 

 barred with blackish ; lateral feathers black, with dingy ashy tips and a 

 series of brownish white spots along outer webs; chin, throat, breast, 

 and middle of belly white, faintly washed with brown and spotted on 

 breast and flanks with black ; flanks posteriorly and entire crissum cin- 

 namon brown, brightest on under tail coverts. 



Measurements of type.— Wmg 7') ; tail 76 ; culmen 19.5; tarsus 24. 



General notes.— This species is nearest //. gnluris, from whicli it is easily 

 distinguished by the blackish brown crown, blackish postocular stripe, 

 and darker l)rown back. The black spots on breast and flanks are rounded 

 instead of being mainly pointed anteriorly (and thus subtriangular), as in 

 H. gularis. Typical specimens of H. gularis in the Biological Survey 

 Collection from the Sierra Nevada de Colima, southern Jalisco, and from 

 the Sierra Madre of southern Sinaloa and the Nayarit Mountains of Tepic, 

 just west of I^>olanos, outline the known range of this species, and the 

 specimens from the mountains of Sonora referred to //. gularis by Salvin 

 and (iodman (Ibis, 1889, p. 235) are, no doubt, referable to //. slridnhis. 



Myadestes obscurus cinereus subsp. nov. Sonora Solitaire. 



Type No. 164262, $ ad., TJ. S. Nat. Mus., Biological Survey Collection, 

 from mountains near Alamos, Sonora, Mexico. Collected January 3, 

 1899, by E. A. Goldman. 



Distribution. — Arid mountains of southern Sonora and adjacent part of 

 Sinaloa, Mexico. 



Suhspecific c/(ar«dcrs.— Most like M. yadestes o. insaluris but with the ashy 

 gray of upper parts even paler than in that form and extending ferther 

 down over fore back : rump and middle tail feathers clearer ashy and 

 interscapular area less suffused with brown. Under ])arts nuich as in 

 M. 0. occidentalls but clearer ashy, with white area on abdomen more re- 

 stricted tluin in iii.^tilarl.s. 



^feasnrelnents of I y])i:—\\\u<i lO-i; tail 104; culmen 11.5; tarsus 20. 



General notes. — This form equals Alyadeste.'^ o. occidentalis in size but is 



