Vol. VI] SWARTH— RACES OF BEWICK WREN 67 



Thryomanes bewicki spihtrus (Vigors) 



Type locality — Near San Francisco or Monterey, Cali- 

 fornia. 



Range — Coast region of central California (Santa Cruz 

 faunal district) ; southern and eastern sides of San Francisco 

 Bay, south to southern end of Monterey Bay. Restricted to 

 the region west of the Coast Range. 



Specimens examined from the following localities: Contra 

 Costa County: Martinez, 1. Alameda County: Berkeley, 

 3 ; Oakland, 7 ; Piedmont, 2 ; Alameda, 1 ; San Lorenzo, 1 ; 

 Haywards, 2. San Mateo County : La Honda, 1 ; Woodside, 

 2; Pescadero, 2. Santa Clara County: Palo Alto, 24; Mil- 

 pitas, 1. Monterey County: Pacific Grove, 3; Monterey, 1. 

 Total, 51. 



Distinguishing characters — Most nearly like T. b. marinen- 

 sis, whose range adjoins that of spilurus at the north, but of 

 lighter brown coloration dorsally, and of slightly greater size. 

 Compared with drymoecus it is brighter reddish above. From 

 charienturus it differs in deeper red coloration, and in differ- 

 ent proportions. In spilurus the tail is slightly shorter 

 than the wing ; in charienturus the tail is longer than the wing. 



Remarks — Thryomanes bewicki spilurus, as here restricted, 

 ranges over a limited area in the central coast region of Cali- 

 fornia between San Francisco and Monterey bays. Geograph- 

 ically it occupies a position between marinensis and charien- 

 turus, and analysis of the characters of spilurus demonstrates 

 that in this latter respect also it is a transitional step between 

 the races to the northward and to the southward. Palo Alto 

 specimens present the best manifestation of the characters of 

 spilurus of any of the series at hand. These birds are quite 

 uniformly bright reddish above, the only exceptions being two 

 or three individuals, rather duller colored, and apparently 

 verging toward drymoecus. 



Birds from the east shore of San Francisco Bay (Berkeley, 

 Oakland, etc.) present a certain peculiarity of coloration, for 

 with hardly an exception they are extremely dark and sooty 

 in appearance, as remarked by Oberholser (1898, p. 439). 

 This is undoubtedly partly, but not altogether, due to smoke 

 stain, the darkenirtg effect of which has been noted in certain 



