134: LIFE OF A TREE. 
earth-embracing roots, and hence they have 
neither the power, nor probably the instinct, if 
we can say so much about a tree, to remove. But 
we have no doubt the singular movements of 
which we are about to speak, will equally interest 
the reader. 
The sensitive plant, Mimosa pudica, is a well- 
known instance of these singular movements. 
If one of its tender leaflets is gently pinched, the 
whole plant seems to resent the injury, and all 
the leaves of that branch first fall low and droop, 
and this extends itself, if the touch is pretty sharp, 
through every branch and leaf, until the plant 
droops from head to foot. It does not recover 
itself for some time afterwards. De Candolle 
informs us of another plant, somewhat resembling 
the sensitive plant in this respect. It is a native 
of Senegal, and is called by the inhabitants, the 
“How d’ye do?” plant, because, when touched, 
its leaves bow down as if about to salute those 
who touch them. He also relates another equally 
singular instance in a plant, a native of Dominica, 
and called, from its peculiar movements, the 
Sentinel plant. While all the other leaves are 
bent down, one is sure to be found erect, and as 
