73 
good species and B. fontinalis is referred to it, while occidentalis 
is almost certainly a variety of alba and fontinalis is a form 0 
microphylla. 
Sakix Monica Watson is kept up though it is not considered a 
species. Salix Nevadensis is ignored though it reaches the region 
he covers. 
He omits all mention of Populus Fremonti var. Wislizeni 
(which may be P. Mexicana) though it is the common form of 
Southern California. 
In the matter of specific description there is not great evi- 
dence of extensive field work, the descriptions are for the most 
ference between a hemlock and a spruce. 
correctness of his treatment of ‘Cupressus. eee 
Cupressus species found about San Diego are not men era 
does not mention the fact that the writer of this regards 
Pinus monophylla as a variety of P. edulis, and that se ee 
anists have gone a step farther and united both with P. cembroides 
