45 
numerable subdivisions and many peculiar species. There are the 
Chihuahua plains, the Yaqui-Sonora region on the floor, and on the 
high plateaus are many valleys and mountain ranges with interest- 
ing floras. The most important are Sierra Madre plateau, the Coa- 
huila ranges, the Mt. Colima region, the Valley of Mexico and simi- 
lar valleys of central Mexico, Popocatapetl, the San Luis Potosi re- 
gion, the Lake Chapala region, and others. 
Passing from the floor of the Great Plateau we find far less 
species differentiation, but almost every range of mountains has a' 
distinctive flora more or less separate from any other. The Colora- 
do Rocky Mountains are interesting and include the Yellowstone on 
the north and New Mexican on the South to Santa Fe. There is the 
Glacier Park region of Montana, the Blue Mountains of Oregon, the 
Sawtooth and Bitterroots of Idaho and Montana, the Wasatch and 
Uintas of Utah, the Deep Creek in western Utah, the Schell Creeks 
and Clover mountains of eastern Nevada and the West Humboldts 
of western Nevada, and also the Malheur range, the Pioche region, 
the Charleston peaks, the Funeral and Panamint mountains, the Pro- 
vidence range, the White mountains of California, the Cascades, the 
Coast range, the Sierras, the San Bernardinos, the San Jacintos, San 
Pedro Martir, Mogollons, Sandias. Catalinas, Santa Ritas, Chiricahuas, 
Huachucas, Floritas, and several ranges in western Texas, It would 
be too tedious to go into the floras of each, and in addition they are 
only local and feather into the adjoining regions. 
The distribution of Astragalus at the far north has nothing 
of importance. A few species range throughout the forest region to 
the tundras of the Arctic. There are no distinct floral regions worthy 
of note beyond the Saskatchewan, nor has the Atlantic region any 
significance beyond the usual life zone limits. The peaks of New Eng- 
land have a few alpine and high latitude species. 
