606 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 2 



of California. The perpallidus group is distinguished by a high degree 

 of contrast between pileum and dorsum, pale dorsal coloration, and a 

 black pectoral spot. These are the birds of Arizona, New Mexico, 

 Texas, and parts of Mexico. 



Throughout its range the species is strictly resident and highly 

 territorial. Movements within each population can only be inter- 

 preted as dispersal of young individuals. 



The climate varies considerably within the range of this species, 

 with maximum rainfall and lowest temperatures in southern Oregon 

 and minimum rainfall and highest temperatures in the deserts of the 

 southwest. In the coast ranges and in the foothills of the Sierra 

 Nevada, which may be considered typical of the habitat of this 

 species in California, the temperatures are moderate and rainfall is 

 from 10 to 20 inches a year. These factors appear to limit the dis- 

 tribution of this species only when they result in little or no brush 

 vegetation. 



Within its range the brown towhee meets with the closely related 

 Abert's towhee (PipUo aberti) to which it is very similar in appear- 

 ance. Abert's towhee is a bird of desert riparian and lacustrine 

 vegetation, a much more restricted habitat than that of the brown 

 towhee. In southern Mexico another close relative, Pipilo rutilus, 

 is found. The brown towhee also comes in contact with the rufous- 

 sided towhee {Pipilo erythrophihalmus) , a ground-nesting species 

 inhabiting more dense vegetation than that of its congener. The 

 rufous-sided and brown towhees differ considerably in habits, song, 

 and coloration, indicating a much more distant relationship than 

 that between the brown and Abert's towhees. Davis suggests that 

 fuscus may be related only distantly to erythrophthalmus and may 

 be more closely related to the genus Melozone. 



The brown towhee is primarily associated with the chaparral and 

 secondarily with riparian vegetation. Davis (1951) describes its 

 vegetation requirements as follows: 



The growth form most desu'able for protection and for location of the nest 

 may be provided by many plants or combination of plants. However, the 

 association utilized to the greatest extent is Californian chaparral. Of primary 

 importance in this association are Adenostoma fasciculatum and Ceanothus cuneatus. 

 Both species are widely distributed in the Coast ranges, the Cascade and Sierra 

 Nevada foothills, and the mountains of Southern California. Both extend into 

 northwestern Baja California, and Ceanothus cuneatus extends northward into 

 Oregon. Other important chaparral shrubs are Prunus ilicifolia, Pickeringia 

 montana, Dendramecon rigida, Photinia arbutifolia, and various species of Ardo- 

 staphylos, Rhus, Quercus, Rhamnus, Garrya, and Eriodictyon. The most im- 

 portant trees associated with the chaparral are Arbutus menziesii, various species 

 of Quercus, Pinus sabiniana, and P. coulleri (McMinn, 1939:6). 



The Californian races are found secondarily in associations other than chap- 

 arral. They have been recorded frequently in riparian vegetation, especially in 



