26o PACIFIC YELLOW-THROAT 



abode, many miles of arid unfavorable country often separating neigh- 

 boring colonies." 



Eggs. — 4 or 5, usually 4. Ground color and markings the same in 

 all respects as in the eastern subspecies. Size; a set of 4 from Utah 

 measures, .74X.54, .74X.54, .73X.54 and .75X.54. 



Pacific Yellow-throat 



GEOTHLYPIS TRICHA3 ARIZELA Ober. 



SubspecMc Characters. — In Oregon, as far east, at least, as the Klamath 

 Lakes, Washington, and British Columbia the breeding Yellow-throat shows an 

 approach to the eastern form in the decrease in yellow on the underparts, and 

 the somewhat narrower margin of the grayish border to the black mask. These 

 characters, however, are variable, some specimens having the mask border fully 

 as wide as in extreme examples of occidentalis though it averages a shade 

 bluer in color. 



In central California, whether in the interior or on the coast, the name 

 arizela can be applied with no precision. Breeding specimens from Stockton 

 may be referred to either arizela or occidentalis and, in fact, have been referred 

 to both. A breeding bird from Monterey is assuredly to be referred to occiden- 

 talis rather than to arizela. 



Specimens from Westminster, Ducks, Revelstoke, and Banff exhibit the 

 intermediate character which distinguishes arizela and it may possibly prove to 

 be desirable to restrict this name to the Yellow-throats breeding at the northern 

 part of the range of occidentalis. Wing, 2.20; tail, 2.10; bill, .42. 



General Distribution. — Northwestern United States and southern 

 British Columbia. 



Summer Range. — Northern California, Oregon, Washington, and 

 southern British Columbia eastward, at least, to Banff. (See, however, 

 under a discussion of the bird's characters.) 



Winter Range. — Mexico. 



The Bird and its Haunts. — In the vast tule-grown areas of the 

 Klamath Lake region this bird was even more abundant than I have 

 ever found the eastern form, which, it may be added, it resembles in 

 actions. 



Walter Fisher (MS.) writes of this form: "In California the 

 Pacific Yellow-throat breeds in favorable spots west of the Sierra Ne- 

 vada and north of the Tehachapi Mountains. Like other Yellow-throats 

 it is local in occurrence, frequenting rule patches that border sloughs, 

 lakes or sluggish rivers. In the northwest coast district the patches of 

 high grass and tule are usually of limited extent, so that the colonies are 

 small, but along the sloughs of Clear Lake the birds are abundant." 



Song. — The song resembles in form that of the eastern Yellow- 

 throat but differs from it sufficiently to sound somewhat strange and 

 unfamiliar to ears accustomed to the song of North Atlantic coast birds 



