March, 1907.] GrINNELL & GrINNELL: CALIFORNIA BUTTERFLIES. 37 



THE BUTTERFLIES OF THE SAN BERNARDINO 

 MOUNTAINS, CALIFORNIA. 



By Joseph Grinnell and Fordyce Grinnell, Jr., 

 Pasadena, Calif. 



Three summer months in 1905 and two in 1906 were spent by the 

 senior author in natural history field-work in the San Bernardino 

 Mountains, California. Although attention was paid more particu- 

 larly to vertebrates, many insects were obtained, and of these nearly 

 1000 Lepidoptera were secured, representative of the 51 species of 

 butterflies enumerated in the present paper, besides a number of moths. 

 The majority were taken about the head of the Santa Ana River, at 

 elevations ranging from 5,000 to 8,500 feet. 



During the season of 1906 Hilda Wood Grinnell was most active 

 with the net, and several of the rarities were discovered through her 

 continued watchfulness. Although we were not inclined to collect 

 vast series (in fact our time had to be apportioned among several 

 subjects), yet we were always on the lookout for things not previously 

 collected. 



We were especially interested in noting the zonal ranges of certain 

 butterflies which seemed to be as sharply limited as some birds and 

 mammals. And, as with the latter, certain other butterflies seemed to 

 be spread broadcast, indifferently. But here it must be kept in mind 

 that while imagines may range extensively, vertically as well as hori- 

 zontally, the larvae may feed exclusively on certain plants which are 

 of very limited range. As with birds, it is the breeding range we 

 should try to determine, though this is most difficult. 



The life zones represented on the San Bernardino Mountains 

 within the region worked include the Upper Austral, Lower Transi- 

 tion, Upper Transition, Canadian and Hudsonian. Each of these 

 possesses many restricted and characteristic plants and animals. Nat- 

 urally the former are most serviceable as earmarks. 



The Upper Austral, which completely encircles this mountain 

 group, the higher zones being arranged more or less concentrically 

 within, is represented on the two slopes by remarkably different divi- 

 sions or faunae. It is characterized on the Pacific side by the scrub 

 oak (^Quercus dumosa), grease-wood i^Adenostoma fasciculatuni), and 



