28 Historiggl Sketch of the Science of Botany  {January, 
enumerates fifty-nine species, a number of which he degraded to 
the rank of sub-species in his Monographia Salicum, 1863. He 
is the author of the genus Salix in Decandolle’s Prodromus. 
Besides the Rocky mountains and California, another large 
field opened for exact exploration. The Mexican war and the 
acquisition of new territories caused a long series of expeditions 
to California and those tracts of land which form with West Texas: 
the North Mexican botanical province. 
In June, 1842, Lieut. Fremont set out from the mouth of the 
Kansas river, followed that river about one hundred miles, passed 
over to the Platte river, traveled up the river to the junction of ~ 
the north and south fork, where the party divided, one part fol- — 
lowing the north fork to Fort Laramie, the other proceeding 
along the south fork to Fort St. Vrain, and from there to Fort 
Laramie. Then the expedition followed the north fork and the — 
Sweetwater river up to South Pass, and the Wind River moun- 
tains, the highest peak of which, afterwards called Fremont’s Peak, 
he ascended. Returning, the Platte river was followed to its 
mouth. The collection of plants, consisting of 352 species, con- 
tained fifteen new ones, described by Torrey. 
The collections of Fremont’s second expedition, during the 
years 1843 and 1844, which extended to Oregon and California, — 
were greatly damaged, so that in many instances it was extremely — 
difficult to determine the plants. Torrey furnished the descrip- 
tion of a few new genera and species, which, with four plates, was _ 
published in App. C. to Fremont’s Report. One of these new 
genera he named Fremontia, but this name was afterwards 7 
withdrawn, as Nees had already described the plant under the ~ 
name Sarcobatus, and Fremont’s name was transferred to another — 
new Californian genus of the order of Sterculiacez. 
Two other expeditions were undertaken by Fremont in 1845- — 
1846 and 1848, extending to California. Large collections were J 
made again, but the greater part of them were destroyed by the — 
same mishaps. Some of the new genera that were saved for €x- — 
amination were described and published in 1850, by Professor . 
Torrey in the Smithsonion Contributions, as “ Plantæ pyes 
ianæ,” with ten beautiful plates. 
Emory’s military expedition traversed in June and July, 1846. 4 
the plains from Fort Leavenworth to the bend of the Arkansas, — 
followed this river to the Pawnee fork, crossed the Raton moun- 
