Strand and Dune Flora of the Pacific Coast 171 



1925). It belongs to the subgenus (or genus) Hor\elia, which, 

 according to Rydberg (1898), comprises about 50 species, all 

 natives of western North America. The group Cuneatae has 

 nine species, all inhabitants of California and Baja California. 



Croton californicus Muell. Arg. (fig. 9^) is a very abundant 

 and typical member of the dune shrub community. It ranges 

 along the coast from San Francisco Bay southward to the tip of 

 Baja California. It also occurs on both shores of the Gulf of Cali- 

 fornia. At the northern end of its range it is confined to the im- 

 mediate vicinity of the sea, but farther south it spreads inland. 

 It is frequent in the valleys of southern California, and is re- 

 ported from scattered localities in southern Nevada, Utah, Ari- 

 zona, New Mexico, and Texas. Interior stations east of California 

 are not plotted on the map. In addition to the typical form, which 

 is mainly coastal, Ferguson (1901) recognizes three varieties, 

 mainly of the interior. The genus Croton, numbering more than 

 600 species, is chiefly tropical. Ferguson recognizes 24 species as 

 occurring in the United States. These range across the southern 

 part of the country from the Atlantic to the Pacific, several ex- 

 tending into Mexico. C punctatus Jacq., a near relative of C. 

 californicus, is a seashore plant upon the south Adantic and 

 Gulf coasts. 



Monardella crispa Elmer (fig. ^e) is found with the dune 

 shrubs and also on sand that is imperfecdy stabilized. It occurs 

 in the Santa Maria dune region, and at Point Reyes. Monardella 

 is a genus of moderate size centering in California, especially in 

 the dry foothill regions, with a few species in the central Rocky 

 Mountains. 



Castilleja latifolia H. and A. (fig 9/) is frequent within its 

 range; it occurs also on blufTs, but always close to the sea. It ex- 

 tends from Westport, Mendocino County, south to Point Sur, 



