34 N'elson — JVorth American Mainland 3Iyiarchus. 



central southern Texas south to northern Lower California, central 

 Sonora and at least to Zacatecas on the southern part of the Mexican 

 tableland. 



ir7«^'v /YOi^e. — Migrates over all of Lower California and the rest of 

 Mexico (except the southeastern tropical parts) at least to Guate- 

 mala. 



Zonal distribution. — L^pper and lower Sonoran. 



Specific clinracters. — Upper parts grayish brown: crown a little darker 

 than back; inner webs of tail feathers mainly rufous but tipped more or 

 less broadly with dusky on outer feather. 



Description of fresh phimage. — Top of head grayish bistre brown, 

 iisually a little darker than back; back dark hair brown, becoming paler 

 and grayer in worn plumage; back of neck sometimes paler or more ashy 

 than back; upper tail coverts dark hair brown, sometimes edged slightly 

 with raw umber or russet (never in worn specimens); wing 

 coverts and tertials broadly, and secondaries narrowly edged with 

 grayish white; primaries (except first) edged with rufous; primaries, 

 secondaries, tertials and top of tail feathers clove brown, palest on ter- 

 tials; underparts from chin over breast and wash over fore-part of ab- 

 domen pale cinereous gray, becoming whitish in faded plumage; abdo- 

 men and under tail coverts primrose yellow (becoming whitish in faded 

 plumage); basal half or three-fourths of outer web of outer tail feather 

 distinctly whitish, latter color replaced on distal end by dusky line 

 bordering shaft and widening toward end of feather in proportion to ex- 

 tent of same color on inner web of feather; inner web of outer feather 

 cinnamon rufous from base to middle of feather, the rufous replaced along 

 shaft at varying distances beyond this to within one-fifth of length from 

 tip by dusky line gradually broadening to include entire tip and sometimes 

 extending back as narrow border some distance along inner side of 

 feather; extent of dusky tip varies from narrow border to half an inch 

 or more; tips of other tail feathers except middle pair with similar 

 pattern but amount of dusky decreasing inward. 



Female. — Dusky on inner web of outer tail feather not rarely restricted 

 to narrow wedge shaped line along shaft on terminal part of feather 

 much as in M. nuttingi; but such birds are readily distinguishable by 

 their much greater size. 



Young in first plumage (Pecos River, northwest of Comstock, Tex., 

 August 1, 1902). — Top of head dull rusty brown; back dull hair brown; 

 upper tail coverts and tail mainly light cinnamon rufous, including middle 

 pair of feathers; outer web of outer feather paler, except tip; narrow dusky 

 shaft lines on distal third of all tail feathers and broad dusky band along 

 basal two-thirds of shaft except on middle pair; vinderparts pale ashy 

 whitish to breast: abdomen and under tail coverts yellowish white. 



Measurements. — Averages of ten adult males from western Texas: 

 Wing, 101.5 (99-103); tail, 95.2 (93-98); culmen, 18.9 (17.5-20); tarsus, 

 23.7 (23-24). 



Averages of ten adult females from western Texas: Wing, 94.7(91-98); 

 tail, 87.9 (82-93); culmen, 17.9 (16.5-19); tarsus, 22.7 (21-24). 



