512 University of California Publications in Zoology | Vou. 17 
Monterey County: Headwaters of Big Creek, 2. Ventura County: Mt. Pinos, 
2. Kern County: Kiavah Mt., 7000 ft., near Walker Pass, 2. Tulare County (not 
typical): Taylor Meadow, 7000 ft., 8; Cannell Meadow, 7500 ft., 1; Pine Flat, 
7500 ft., 1; Long Meadow, 7700 ft., 1; Sirretta Meadows, 9000 ft., 3; Trout 
Creek, 6000 ft., 10; near Trout Creek, 7500 ft., 2; Jackass Meadow, 7750 ft., 3; 
Troy Meadows, 8000 ft., 1. Los Angeles County: Mt. Wilson, 25; Buckhorn 
Canyon, near Mt. Waterman, 2; near Pasadena, 9 (vagrants); Verdugo, 1 
(vagrant). San Bernardino County: near Cucamonga, 1; San Bernardino Mts., 
35; Victorville, 3 (vagrants). Riverside County: San Jacinto Mts., 29; Thomas 
Mt., 1; Santa Rosa Mts., 10. Orange County: Santa Ana Mts., 3000 ft., 1 
(vagrant?). San Diego County: Julian, 1; Cuyamaca Mts., 6. 
General remarks.—In making use of the intrinsic color characters, 
which are important here in distinguishing subspecies, it is, of course, 
essential that the effects of extraneous factors be taken into account. 
Prolonged wear and fading evidently serve to weaken the intensity of 
the color tones, more especially the buffy ones. Then, too, chickadees 
seem peculiarly susceptible to discoloration by smoke, soot and charred 
wood; for example, our series from Cisco and Blue Cain, stations 
along the Central Pacific Railway over the Sierra Nevada, even though 
taken in September and October almost immediately after completion 
of the fall molt, are obviously more or less begrimed with soot. On 
the other hand, the autumn- and winter-taken series from the Yosemite 
region and from the Siskiyou Mountains are clean, and show their 
intrinsic color tones to good advantage. 
Intergradation undoubtedly connects the four races of the Moun- 
tain Chickadee into a continuous series of forms. Abundant material 
at hand from that portion of the Sierra Nevada immediately south of 
Mount Whitney shows complete transition from Penthestes gambeli 
baileyae to P. g. abbreviatus; in fact, many of the specimens ean only 
be placed arbitrarily in one category or the other. Several examples 
from the vicinity of Mono Lake, in Mono County, California, and 
from along the west flank of the Sierras in Inyo County, insensibly 
bridge the interval between P. g. abbreviatus and P. g. inyoensis, espe- 
cially when considered in connection with the individual variation to 
which each race is subject in about normal degree. 
Material at hand from different parts of the Great Basin is unsat- 
isfactory either in that it is seanty or because of the worn state of the 
plumage. A summer-taken series of 13 Mountain Chickadees (nos. 
8952-8964, Mus. Vert. Zool.) from the Pine Forest Mountains, Hum- 
holdt County, Nevada, shows in color no approach to P. gambeli gam- 
beli. In this respect it is like P. g. inyoensis, but the tail averages 
nearly as short as in P. g. abbreviatus. Taking all features into 
a 
