PEOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 375 



Adult in spring. — Above uniform russet-olive (much as hi IT. ustulat a) ; 

 jugulum and lower part of throat pale buff, as in ustidata, much lighter 

 than in fuscescens, the markings, however, small and narrow as in the 

 latter. Sides of head dull grayish, without trace of lighter orbital 

 ring ; sides of breast, sides, and li'auks ash-gray (rather deeper than in 

 fuscescens), the breast very faintly or not at all spotted with darker. • 



Adult in fall and rcinter. — Above darker, more umber, brown; jugu- 

 lum and lower part and sides of throat deeper buif, with nuich darker 

 spots. 



The general appearance of this bird at first glance is more that of 

 H. ustuiata than true H. fuscescens, the upper paits and anterior lowei' 

 parts being quite similarly colored. A close examination, however, im- 

 mediately reveals radical differences, the most important of which is 

 the total absence of any light orbital ring, which is always i^resent, and 

 very distinct, in ustuiata. The wings and tail, instead of being ap- 

 preciably more rufescent than the back and rump are, on the other 

 hand, less so ; the buff of the jugulum gives way very abruptly to the 

 ■ash-gray on the sides of the breast, and the spots end quite as abruj)tly, 

 the breast being plain ash-gray laterally, and white medially, with very 

 indistinct spots of grayish between the white and the gray. In ustuiata 

 the sides are decidedly brown, with very distinct transverse spots of a 

 darker shade of the same color entirely across the breast. Another ex- 

 cellent character consists in the color of the axillars and lining of the 

 wing, which are light grayish in the present bird, and deep brownish 

 buff in ustuiata. 



The differences from typical fuscescens of the Atlantic States, as in- 

 dicated in the above diagnosis, are exceedingly constant. 



A specimen from Chicago, 111., in the collection of 11. K. Coale, of 

 that city (No. 1568, Coll. H. K. C, Sept. 10), is referable to this race, 

 and is evidently a fall straggler from the Rocky Mountain district. It is 

 even more olive above than most specimens from that region, having 

 almost exactly the same shade of color as a fall specimen of H. swainsoni 

 from Massachusetts, the latter, however, an unusually brown example. 

 The entire absence of any light orbital ring, the narrow, almost linear, 

 streaks of the jugulum, and the peculiar proportions, however, refer it 

 at once to fuscescens. 



I have called this new form salicicola on account of its marked pre- 

 dilection for willow thickets, to which, along the streams in the valleys 

 and lower canons of the Eocky Mountain region, it is chiefly confined 

 during the breeding season. 



