38 BAMBOOS [cH. II 
rivers. Most of these Bamboos are xerophytes. Bamboos 
are neither confined to the tropics, nor to warmer regions, 
however, for species are known from distinctly cool regions 
—e.g. South America—or even from near the snow line— 
e.g, Chili, the Himalayas, Japan, We., and the number of 
species known as hardy is increasing annually, as 1s evident 
on examining our larger English gardens. 
The permanence and character of extensive grass- 
lands, especially prairies, savannahs, and steppes, are much 
affected by the periodical firmg they are exposed to in 
the dry season, and large tracts of country in various parts 
of the world would doubtless bear forests or other vege- 
tation if not thus fired, while in other cases the herbage 
would be differently constituted were firing discontinued. 
The following chapter embodies an attempt to classify 
our British grasses solely for purposes of identification 
when not in flower. It is not claimed that the arrange- 
ment is the best possible, nor that it is complete, and 
I need hardly say that corrections will be gratefully 
received. 
