DISTRIBUTION OF AMERICAN FORESTS 
Finally, within the eastern forests: a 
restricted region at the southern end of 
Florida, including the Keys, may prop- 
erly be separated from the rest. For 
here is found a distinctively tropical 
vegetation, differing entirely in char- 
acter from the forest flora to the north. 
Many trees indigenous to the West 
India Islands have established them- 
selves upon this small area, on which 
the number of species exceeds that of 
any region of equal extent within the 
United States, not excepting even the 
varied forest growth of the Mexican 
border line, to which alone it might be 
worthily compared. 
Separating the forest floras of the 
western and eastern United States, lies 
the broad region of prairies and plains. 
Though trees are found for the greater 
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