1903 | FLORA OF SOUTHERN CALIFORNIA 261 
the last one disappears at Santa Barbara. They are enumerated 
below 
PENINSULAR SPECIES ALONG THE COAST. 
Acalypha Californica Cneoridium Californicum Mamillaria dioica 
Agave Shawii Dithyrea Californica Opuntia prolifera 
Arctostaphylos diversifolia Frankenia Palmeri Opuntia serpentina 
accharis sarothroides Isomeris arborea Simmonsia Californica 
Seat Californica Iva Haysiana Viguiera laciniata 
Cereus Emo 
The hee area comprises two fairly distinct subareas. 
These probably owe the differences of their floras to the fact 
that one is more exposed than the other to the fogs and humid 
air of the ocean. The line separating them follows those eleva- 
tions which intercept the direct action of these influences; 
namely, the seaward flanks of the Cuyamaca and Palomar Moun- 
tains, the Temecula Range, and the lower hills which continue it 
beyond the Santa Ana River. 
The district between this line and the Pacific Ocean may be 
called the Coastal subarea; that between this line and the San 
Bernardino Range constitutes the Interior subarea. The latter 
subarea includes the San Fernando, San Bernardino, and San 
Jacinto Valleys. Where the wide Los Angeles Valley opens out 
to the sea the two subareas coalesce, and some of the most char- 
acteristic Coastal species are carried inland to the base of the 
San Gabriel Mountains. 
The most evident characteristic of the Coastal subarea is the 
prevalence of oaks. Its rolling hills are covered commonly with 
open groves of Quercus Engelmanni and Quercus agrifolia; indeed, 
the first of these oaks and Rhus laurina may be considered the 
characteristic arboreal plants of this subarea. Its chaparral is 
much more largely composed of scrub-oak, mostly Quercus 
dumosa, than that of the Interior, where Adenostoma fasciculatum 
is the principal shrub. But the Interior subarea differs from the 
Coastal mostly in a negative way; the latter possessing fully one 
hundred species which do not extend into the former. Among 
these are eight species of Atriplex, five each of Chorizanthe and 
Phacelia, four each of Gilia and Antirrhinum, and three each of 
Astragalus, Calochortus, Cotyledon, and Salvia. 
