BOTANY. 689 
Kentucky to Texas and the Gulf, has about 112 to 118 species, 60 
or 65 of which attain a height of 50 feet, which the author also 
analyzed. West of these last two districts, this treeless belt, ex- 
tending entirely across the continent from the Gulf of Mexico to 
the Arctic Ocean, is described, and its characteristics within the 
limits of the United States are mentioned. It is 350 miles wide 
in its narrowest part, between latitude 36° and 37°, and 800 miles 
wide on our northern border. The Rocky Mountain region is 
next considered. This consists of from 28 to 30 species, but a 
vastly smaller number making up the timber region. Perhaps not 
over half a dozen species constitute by far the larger part. No 
hard woods are abundant in any of the forests west of the Great 
Plains, although hard woods occur, particularly in the southern 
and western part, as scattered trees rather than as forests. Be- 
tween the Rocky Mountains in the Sierra Nevada is a desert 
or sparsely wooded region, which extends southward to Mexico, 
uniting on its southern part with the treeless expanse which ex- 
tends from the Atlantic to the Pacific along our southern frontier, 
and throwing out a spur entirely across the Rocky Mountains 
_ hear the Pacific Railroad, connecting it with the tréeless plains on 
_ the eastern side. This great treeless district varies very much in 
its different regions, has quite a large number of species of inter- 
est to botanists, and some few of economic value. The only 
forests within it are forests of conifers, occurring on the moun- 
tains, of which the largest one is in Arizona and is 400 miles 
$ long, the limits of which have recently been. demonstrated by 
Lieut, Wheeler’s Expeditions. Here followed an analysis by the 
_ Author of the flora of the region west of this Desert ; of California, 
: Washington Territory, and Oregon, where were found the grandest 
forests, perhaps, on earth, and the noblest trees. The number of 
 “Pecies of these latter is quite large, but in any one region the 
_ ‘Sumber of species is small. With one single exception all of the 
_ ees within the United States which attain a height of 200 feet 
are found in this district. The forests are entirely of cone bear- 
_ ing trees and the number of species is large, the number of timber 
« trees being very large and their size and value also being gress. 
h Washington Territory official reports state that the land will 
_ Produce from 25,000 to 300,000 feet per acre, and that there are 
_ "ast tracts “that would cover the entire surface with cord wood 
_ MER. NATURALIST, VOL. VIII. 44 > 
ER A ra e er 
