298 RYDBERG: PHYTOGEOGRAPHICAL NOTES 
are found quite a number of species which have immigrated from 
the Northern Rockies or from the mountains of the Great Basin. 
The southern part of the Wasatch Mountains, including the 
Sevier Range, the Henry Mountains, and other ranges west of 
the Colorado of the West (District 11), have a flora characteristic 
of the Basin Mountains. The Montane flora consists to a great 
extent of species common to the Rockies, the Basin Mountains, 
and the Sierra Nevada. The La Sal and Abajo Mountains, in 
Southeastern Utah (District 12) have a mountain flora almost the 
same as that characteristic of the main range of the Southern. 
Rockies in Colorado. 
The plants of the Montane Zone of the Rocky Mountains may 
be classified in the following categories. These are practically the 
same as those in the Subalpine Zone, with, however, some modi- 
fication. 
I. Transcontinental Species. 
II. Species common to the Rockies and the ede Zone of the 
East. , 
III. Species common to the Rockies and the Pacific Mountains. 
IV. Endemic species. 
I. Transcontinental Species 
The transcontinental species, as well as most of those com- 
mon to the Rockies and to the East, consist partly of forest species, 
most of which have migrated around the Saskatchewan Plains, 
partly of water, meadow, and thicket species which have followed 
the watercourses across the plains. The former consist to a 
great extent of species common to the Subalpine and Montane 
Zones in the Rockies and hence also to the Hudsonian and Cana- 
dian Zones of the East; the latter consist mostly of species found 
also in the Submontane and Transition (or Alleghanian) Zones. 
Many of the water and bog plants, however, are not found on 
the plains and hence must have followed the woods. 
A. TRANSCONTINENTAL SPECIES RANGING THROUGHOUT THE 
ROCKIES 
Here I have included species which are found in the main 
ranges of both the Northern and Southern Rockies. Many of 
