1920] Swarth: Revision of Avian Genus Passerella 159 



Range. — In summer the extreme northeastern corner of California, 

 in the mountains of Modoc and Lassen counties ; north into central 

 Oregon; east of the Cascades. The northernmost specimen at hand 

 is from Warmspring, Crook County, the easternmost from Burns, 

 Harney County. Winter home unknown. 



Specim€7is examined. — 89 (see list, pp. 201-202). 



Distinguishing characters. — Of the Schistacea group (see p. 89). 

 Bill intermediate in size between schistacea and mariposae; of about 

 the same size as in 7nonoensis, but more slender and attenuated than 

 the short and rather heavy bill of that subspecies (see fig. F). Color- 

 ation more brownish than in mariposae and monoensis ; about as in 

 schistacea. Wing and tail measurements somewhat less than in mari- 

 posae, about the same as in schistacea (see table 4). 



Remarks. — Size of bill will suffice to distinguish fulva from any 

 of the other fox sparrows of the Schistacea group save monoensis. 

 From the latter form fulva may be told by the somewhat differently 

 shaped bill, and by difference in coloration. In worn summer plumage 

 color differences are more or less obscured, but in freshly molted fall 

 specimens they are readily apparent. 



The large series of breeding birds at hand from the Warner 

 Mountains, California, is quite uniform in appearance throughout. 

 Breeding birds from various points in central Oregon exhibit consider- 

 able diversity in size and shape of bill and in relative grayness and 

 brownness of color, though all, I believe, are best referred to fulva. 

 This variation is in accordance with the geographical position of 

 the several specimens, showing different degrees of intermediateness 

 between fulva, schistacea, and mariposae. Birds from extreme 

 southern Lake County are typical fulva. One specimen from Burns, 

 Harney County, the easternmost point represented, in size of bill 

 approaches schistac&a. Examples from Fort Klamath and Sisters, 

 the westernmost points of record, have larger bills, apparently tending 

 toward mariposae. These latter specimens also are decidedly grayish 

 in color, as compared with Warner Mountains birds, in this respect 

 again showing an approach to mariposae. 



There is an abundance of breeding specimens of fulva at hand, and 

 from enough different localities to give a fairly accurate idea of the 

 summer habitat of this form, but there is practically no material that 

 would serve to shed light on migration route and winter home. There 

 is a specimen in the Mailliard collection (no. 4253), a typical example 

 of fulva, collected at Eagle Lake, Lassen County, October 1, 1899 ; 

 and one in the collection of Allan Brooks, collected by A. Van Rossem 



