BIEDS OP NOKTH AND MIDDLE AMEBIC A. 655 



ft. Larger; adult male averaging, wing 63.5, tail 54, exposed culmen 25.6, tarsus 

 19.6; adult female, wing 60.5, tail 51.3, exposed culmen 21.7, tarsus 18.5. 

 (Northeastern and east-central portion of Mexican plateau.) 



Catherpes mexicauns albifrons (p. 657) 

 bb. Smaller; adult male averaging, wing 58.2, tail 50.5, exposed culmen 20, tarsus 

 17.7; adult female, wing 57.2, tail 49.5, exposed culmen 18.3, tarsus 17.3. 

 (Colorado, Utah, Nevada, southeastern California, and parts of Arizona.) 



Catherpes mexicanns couspersns (p. 658) 



Variously intermediate between the two smaller northern and two larger southern 



forms, as characterized above. (Texas, New Mexico, Arizona, southern California, 



Lower California, Sonora, and Chihuahua. ) .Catherpes mexicanns polioptilTis (p. 660) 



CATHERPES MEXICANUS MEXICANUS (Swainson). 

 MEXICAN CANYON WREN. 



Adults {sexes alike). — Above, deep sepia or bistre brown, the back, 

 scapulars, and rump (especially the last) more chestnut-brown or van- 

 dyke, the whole surface (except wings) more or less distinctly vermicu- 

 lated with dusky and more or less profusely dotted or flecked with 

 white;" upper tail-coverts chestnut with a subterminal small, blackish 

 spot of dusky, and usually one of whitish, often with additional indis- 

 tinct narrow, blackish bars, very rarely wholly immaculate; tail clear 

 chestnut or deep cinnamon-rufous, crossed (on both webs) by distant 

 narrow bars* of black, these much broader on the lateral than on the 

 middle rectrices; malar and suborbital regions, lower half (approxi- 

 mately) of auricular region, chin, throat, and upper chest immaculate 

 white; rest of under parts rich chestnut, fad,ing anteriorly (on lower 

 chest) into pale cinnamon-rufous, the deeper colored (chestnut) por- 

 tion more or less distinctly barred or speckled with black and dotted 

 or flecked with white;" maxilla dusky horn color, with paler tomia; 

 mandible dull whitish (in dried skins) basally, becoming grayish or 

 dusky terminally; iris brown; legs and feet blackish or dark brown. 



Young. — Similar to adults, but upper parts more coarsely vermicu- 

 lated with dusky and with few if any white specks or dots; chestnut 

 of abdomen, etc., duller, immaculate, or with very indistinct narrow 

 dusky bars, mostly on flanks. 



Adult maZfi.— Length (skins), 138-156 (147.9); wing, 64.5-72 (68); 



« There is great individual variation in the amount or extent of this white dotting 

 or speckling, which rarely is so sparse as to be nearly absent. Occasionally the white 

 markings take the form of short streaks, but usually they are more or less roundish 

 in form. 



6 There is great individual variation in the width of these black bars, those on the 

 middle rectrices varying (on different specimens) from less than one millimeter to 

 nearly two millimeters in width, those on the lateral rectrices from about one and a 

 half to three millimeters. 



"The white speckling sometimes obsolete, especially in worn summer plumage. 



