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



and dorsum; whiter, less buffy mid-ventral area; pallor of the posterior 

 part of the throat patch; and longer bill. In most characters, it is 

 intermediate between senicula and albigula, which occurs to the south 

 in the cape region of Baja California. The intermediacy of aripolius 

 between senicula, a typical representative of the subspecies of the 

 brown towhee found on the Pacific Coast, and albigula, which re- 

 sembles the geographically isolated subspecies of the southwestern 

 United States and northern Mexico, led Oberholser to the conclusion 

 that all the brown towhees were conspecific and should be regarded as 

 belonging to the single species juscus, rather than divided into the 

 species crissalis, for the birds of the Pacific Coast, and the species /uscus 

 for the towhees to the east and south. The validity of his conclusion 

 has been upheld by other workers. 



The northern limits of the San Pablo brown towhee's distribution 

 occur near the sharp vegetational break between the mixed foothill 

 and desert flora of northwestern Baja California and the extremely 

 rich and varied desert flora that has its northern limits between 

 latitudes 29° and 30° N. The life history of this form is virtually 

 unknown, although it is a common bird over much of its range. 



Distribution 



Range. — The San Pablo brown towhee is resident in the middle 

 section of the peninsula of Baja California, from Play a Maria Bay, 

 lat. 28°55' N. (Grinnell, 1928b) south to Guajademi, lat. 26°35' N. 



Egg date. — Baja California: 1 record, April 26. 



PIPILO FUSCUS ALBIGULA Baird 



San Lucas Brown Towhee 

 Contributed by John Davis 



Habits 



Described originally by Spencer F. Baird (1859) as Pipilo albigula, 

 this well-marked subspecies differs from the race aripolius to the north 

 in its paler, more ruf escent pileum ; paler dorsum, sides, flanks, throat, 

 and under taU coverts; and in its gTeater area of ventral white. 

 Superficially it resembles the canyon brown towhee (Pipilo Juscus 

 mesoleucus) , from which it is separated by a broad geographic hiatus, 

 but it is easily differentiated from that form by its generally smaller 

 size and lack of a black breast spot. Further, its voice is similar to 

 that of the Pacific coast races rather than to that of mesoleucus 

 (Marshall, 1964). 



The San Lucas brown towhee is restricted to the cape region, or 

 terminal third of the peninsula of Baja CaHfornia, from latitude 26** 35' 



