60 Grinnell, A New Screech Owl. [jan. 



31) from Nicasio, Marin County, which is situated in the northern 

 humid coast belt, it remains to name the southern race. 



Otus asio quercinus, new subspecies. 



Type. — Male adult, no. 5678, coll. J. G. ; Pasadena, Los Angeles County 

 California; April 21, 1904; collected by J. Grinnell. 



Diagnosis. — Characters in general like Otus asio bendirei (see Brewster, 

 1. c); differs in paler coloration: Light drab or ashy rather than hazel 

 tones prevail dorsally, while beneath the black markings are sharper in 

 outline, with very little or none of the ferruginous marginings. The restric- 

 tion or absence of ferruginous on the chest, around the facial rim, and on 

 the ear-tufts, is a good character. 



Geographical Distribution. — Records of Screech Owls are well dis- 

 tributed over California west and north of the southeastern deserts, from 

 the Mexican line nearly to the Oregon line. In absence of specimens from 

 most of this area, however, it is impossible to fix the boundary lines accu- 

 rately or to designate the strips of country where intergradation occurs. 

 These can only be inferred, in a general way, from the behavior of better 

 known groups of birds. The material at hand divides up as follows: Otus 

 asio bendirei: Guerneville, Sonoma County, 1; Freestone, Sonoma County, 

 1; Santa Rosa, Sonoma County, 1; San Geronimo, Marin County, 3; 

 Nicasio, Marin County, 1; Oakland, Alameda County, 1; Walnut Creek, 

 Contra Costa County, 4; Palo Alto, Santa Clara County, 2. Otus asio 

 quercinus: west slope Walker Pass, Kern County, 2; Bodfish, Kern County, 

 5; vicinity of Santa Monica, Los Angeles County, 2; vicinity of Los 

 Angeles, 2; vicinity of Pasadena, 7; Mount Wilson, Los Angeles County, 1; 

 Cuyamaca Mountains, San Diego County, 1. 



Remarks. — Birds from the coast belt north of San Francisco Bay 

 are most typical of the race bendirei as here restricted. Specimens from 

 Palo Alto, Santa Clara County, and Walnut Creek, Contra Costa County, 

 show more or less departure towards quercinus. The palest examples of 

 the latter form are from Walker Pass, Kern County; but there is still 

 plenty of difference between these and Otus asio gilmani, of the Colorado 

 River valley. The darkest winter examples of quercinus, from Los Angeles 

 County,. are darker than Palo Alto skins; but this darkness consists in 

 extension of black and not in a pervasion of warm browns as in Marin and 

 Sonoma County bendirei. The latter undoubtedly approach closely to 

 Otus asio brewsteri, recently described by Ridgway (Birds N. and Mid. 

 Amer., vi, 1914, p. 700). I have a topotype of the latter, from Salem, 

 Oregon. This specimen is larger than average bendirei and is decidedly 

 more pervaded with ferruginous tints on the posterior lower surface. There 

 is thus a series of intergrading forms along the Pacific coast, with Otus asio 

 kennicottii at the extreme north, succeeded towards the south by brewsteri, 

 bendirei and quercinus. Of these, so far as yet known, only the latter two 

 occur within the state. The form gilmani is distinct, there being no evi- 

 dence of intergradation between it and quercinus. 



