105 
treat diam., 14; height 8 mm. 
Habitat, Santa Catalina Island, Cal. 
abl 2 . Poy ¢ 
The presence of a colony of land shells, living on Santa Catalina 
[sland today, belonging to the strigosa group, whose metropolis at the 
Plate 4—Helix var. avalonensis—Hemphill. 
orese 1 Fe : : 7 ‘ 
; sent time is several hundred miles distant and northward from this 
Isla gt ¢ : rf 7 : " 
4 and, at an elevation of from four to eight or ten thousand feet above 
LNe seg ra mh : . : : 
Sea level, with a ereat stretch of desert-hke country intervening 
