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WOOLLY AND-“DUSPY: [erwin 
URIOUSLY enough, some plants put on a hairy 
coat for just the opposite reason from the 
one which makes life everlasting clothe itself in that 
fashion. Life everlasting fears lest its leaves throw 
off their water, or perspire too quickly. 
Down by the stream that runs through the meadow 
grow great clusters of the pink-flowered steeple bush. 
If you look at the lower sides of the leaves of the 
steeple bush, you see that they are very woolly. As 
this wool is not between’ the sun and the leaf blade, 
it cannot be meant to protect the leaves ‘from@the 
heat of the sun;* and indeed in this wet meadow, 
close to the river, never mind how quickly the leaves 
throw off their water, the roots can have no difficulty 
in finding close by more than enough to make good 
the -loss. No, the fact 1s that: these” leaves: need @ie 
throw off water very freely indeed to make room for 
the ever-fresh supply that is pushing up the stem, 
and their woolly covering is intended to help them 
do this very thing. Its object is to aid perspiration. 
In swampy places the moisture rises every night from 
the wet ground, and settles on the plants about. The 
little mouths on the under surfaces of the leaves of 
the steeple bush would soon be clogged with the mois- 
ture rising from below, if they were not protected in 
some way; and if they became so clogged, they could 
not throw off the water with which the whole plant is 
charged. Thus, by having this thick coat of hair, the 
