May, 1918 117 



THE DISTRIBUTION OF THE SUBSPECIES OF THE 

 BROWN TOWHEE (PIPILO CRISSALIS) 



By H. S. SWARTH 



WITH MAP AND FIGURES 



(Contribution from the Museum of "Vertebrate Zoology of the University of California) 



THE RECENT acquisition by the Museum of Vertebrate Zoology of series 

 of Brown Towhees (Pipilo crissalis) from sections not previously repre- 

 sented in the collection, notably from many points in the Sierra Nevada, 

 suggested the desirability of an examination of the entire group. The revision 

 of the ranges of the three recognized subspecies, as here set forth, is based 

 mainly upon the collection of the California Museum of Vertebrate Zoology, to- 

 gether with the Grinnell, Morcom and Swarth collections, deposited in that 

 institution. In addition the writer is indebted for the use of specimens from 

 Oregon, loaned by the University of Oregon Museum, through the courtesy of 

 Dr. John F. Bovard, and for the privilege of examining the extensive series of 

 these birds in the collection of J. and J. W. Mailliard, including many speci- 

 mens from critical points not represented in the collection of the Museum of 

 Vertebrate Zoology. Altogether, 383 specimens were used in this study. 



The Brown Towhee is one of several species of birds characterizing the Sono- 

 ran zones in California, that are so closely restricted in their range as hardly to 

 extend beyond the confines of the state. While the Brown Towhee (Pipilo cris- 

 salis) of California is obviously similar to the Canon Towhee (Pipilo fuscus) of 

 the southern Rocky Mountain region, the two being doubtless but recently de- 

 rived from a common ancestry, the wide hiatus now existing between their ranges, 

 together with the lack of intergradation between them, is sufficient justification 

 for their being regarded as distinct species. Indeed, the point is worth empha- 

 sizing that while the range of Pipilo crissalis is comparable to the ranges of cer- 

 tain other Pacific Coast species, such as Psaltriparus minimus, Aphelocoma cali- 

 fornica, and the west Calif ornian races of Pipilo maculatus, all with related 

 forms in the Rocky Mountain region comparable to Pipilo fuscus, the Brown 

 Towhee has no representative race in eastern California such as is possessed by 

 each of the other bird species cited. It seems remarkable that no towhees of this 

 group should exist on the east slope of the Sierras and in the Upper Sonoran zone 

 of the desert mountains. 



The California Brown Towhee was first made known to science through the 

 description by Vigors of Fringilla crissalis fZool. Voy. "Blossom'', 1839, p. 19). 

 His type specimen is listed in the collection of the British Museum as from Mon- 

 terey (Sharpe, Cat. Birds Brit. Mus., xn, 1888, p. 754). Birds from the vicinity 

 of Monterey belong to the reddish-colored race of the central coast region of Cali- 

 fornia (though they do not show the extreme manifestation of the characters of 

 that subspecies), and as there is no question of the migration of individuals to 

 cause confusion, for the Brown Towhees are non-migratory, the name crissalis, 

 applied to a specimen from this region, must, of course, be used for the central 

 coast race. 



The species, long regarded as a subspecies of Pipilo fuscus, was not further 

 divided until the description by Anthony (Auk, xn, 1895, p. Ill) of Pipilo fuscus 

 senicula, from San Fernando, Lower California. In 1899 McGregor (Bull. Coo- 



