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THE CONDOR 
Vol. XV 
the male of arcticus the black of the upper parts is usually more mixed with 
olivaceous or grayish, and the white markings, especially of the scapulars and 
rectrices, are rather more extensive and noticeable, but these differences are not 
especially conspicuous, and at a casual glance the males of the two forms look 
very much alike. There are no differences of moment in size or proportions. 
The females of the forms are so dissimilar, however, as to leave no doubt 
as to the distinctness of the two. In ciirtatiis the female is of the type of the 
western races of P. maculatus in general, with the head and the ground color 
of the upper parts very dark (a dull slate color), with little or no indication of 
brown. In the female of arcticus these same areas are so overlaid with a brown- 
ish suffusion as to give a decidedly different and lighter tone of color to the 
whole bird. This is not a difference requiring close scrutiny for discernment, 
but is something that is readily apparent at a glance, When series of females of 
P. m. curtatus, P. m. arcticus, and P. erythrophthahniis are laid out side by side, 
so as to produce a general “mass effect” of each of the three, the body color of 
arcticus appears to be almost intermediate between the slaty hue of curtatus and 
the brown of erythrophthahniis. 
Thus the study of this material leads directly to the conclusion that the 
name curtatus should not be considered a synonym of arcticus, as has been 
claimed, but that it represents a distinguishable subspecies, apparently inter- 
mediate between the paler colored Rocky Mountain forms and the more intense- 
ly black Pacific Coast races. The material available in the present study shows 
unbroken intergradation from curtatus through falcincllus to the extremely dark 
me galonyx , though not between curtatus and arcticus. 
In this connection the probability suggests itself of the breeding bird of the 
central Rocky Mountain region (Utah, Colorado, etc.) being of the form cur- 
tatus rather than montanus, to which it is at present referred, but the pertinent 
material at hand does not warrant more than the suggestion. 
In differentiating curtatus from the other California forms the pale color of 
the chestnut areas in the former appears to be an excellent character. A molting 
bird at hand from the Warner Mountains (Mus. Vert. Zook, no. 14861), in 
which many of the chestnut-colored side and flank feathers are still partly en- 
sheathed, nevertheless has these parts lighter colored than examples of falci- 
nelliis or mcgalonyx. The absolutely fresh and unworn condition of the feathers 
in this case is conclusive evidence against the assumption that the paler color of 
curtatus is due to fading, being produced by the fiercer heat and sunshine to 
which it is exposed. 
LITERATURE CITED 
American Ornithologists' Union Committee, J. A. Allen, Chairman and Editor. 
1910. Check-List of North American birds. Ed. 3, revised (New York, American 
Ornithologists’ Union), 430 pp., 2 maps. 
1912. Sixteenth supplement to the American Ornithologists’ Llnion check-list of Nortli 
American birds. Auk, 29, pp. 380-387. 
Goldman, E. A. 
1908. Summer birds of the Tulare Lake region. Condor; 10, pp. 200-205. 
Grtnnell, J. 
1902. Check-list of California birds. Pacific Coast Avifauna, 3, pp, 1-98, 2 pis. (maps). 
1911. Description of a new spotted towhee from the Great Basin. Univ. Calif. Publ. 
ZooL, 7, pp, 309-311. 
Linton, C. B. 
1908. Pipilo clementae excluded from Santa Cruz Island avifauna. Condor, 10, p. 208. 
1909. Further notes from San Clemente Island. Condor, 11, pp. 193-194. 
Ridgway, R. 
1899. New species, etc., of American birds. — TV. Fringillidae (concluded) ; Corvidae 
(part). Auk, 16, pp. 254-256. 
1901. The birds of North and Middle America. U. S. Nation. Mus. Bull., 50, part 
1, XXX-1-71S pp., 20 pis. 
1906. “Atratus versus megalonyx.” Condor, 8 , p. 100. 
SWARTH, H. S. 
1905. Atratus versus megalonyx. Condor, 7, pp. 171-174, 1 fig. (map). 
