330 f'nir< rsity of California Publications in Zoology I VlM - 10 



of the above specimens is a half-grown juvenal. All were caught 

 on the gravelly floor of the valley among scattered brush, the 

 station briny within the Lower Sonoran zone. 



Peromyscus maniculatus sonoriensis (LeConte) 

 Sonora White-footed Mouse 



A series of ninety-six specimens was preserved as follows: 

 Round Valley. 9000 feet, three (nos. 1763-1765) ; Tahquitz Val- 

 ley, 8000 feet, twenty-two (nos. 2168-2187, 9332. 9333) ; Straw- 

 berry Valley, 6000 feet, three (nos. 2075-2077) ; Santa Rosa Peak, 

 at 7500 feet, three urns. 2038-2040); Kenworthy, 4500 feet, 

 thirty-one (nos. 1811-1817, 1828-1847. 1858. 9329-9331 | ; Valle- 

 vista, 1800 feet, four (nos. 2255-2257. 9384) ; Fuller's Mill, 6000 

 feet, two (nos. 1649-1650i ; Schain's Ranch, 4900 feet, eight (nos. 

 1648, 1671-1677); Bannine;. 2300 feet, two (nos. 1463, 1464); 

 Cabezon, 1700 feet, fifteen (nos. 1265. 1270-1283); Snow Creek 

 ;it 1500 feet, one (no. 1598); Whitewater, 1130 feet, two (nos. 

 1577. 1599). 



The species was thus captured at almost every collecting sta- 

 tion, from the highest point at which traps were set (Round 

 Valley. 9000 feet) to both the Pacific and desert liases of the 



mountains. As is notoriously tl ase elsewhere, this mouse 



ignores zone limits in its dissemination, occurring in the San 

 Jacinto region from Lower Sonoran to Canadian, inclusive of 

 both zones. Furthermore, it ranges indiscriminately through 

 different associations, being caught among cactus and creasote 

 brush on the dryest desert floor, on sage flats, in chaparral, and 

 in veratrum patches on wet Boreal meadows. 



Our large series of specimens shows such a range of appar- 

 ently individual variation, both as to color and size, as to baffle 

 our attempts at segregation on geographical grounds. A paling 

 deseW wards, as with so many of the mammals of the region, 

 might well be expected; and there may be such, if our senses or 

 methods were refined enough to take proper account of the varia- 

 tion from other than geographical causes. 



Taking the whole series in mass effect, we feel justified in 

 employing for it the one name sonoriensis, thus following Osgood 

 (1909, p. 93) in the disposition of his material. Many individual 



