ON ENVIRONMENT 
which, when it was a slab high up on another 
cactus plant, it knew and feared no danger!” 
Is it more wonderful that, unseen by us, a 
plant should have adapted itself to the desert 
and, through the ages, have armored itself against 
an enemy, than that, before our eyes, in a single 
year, it should meet changed conditions in an 
equally effective way? 
Is it more wonderful that it should grow spines 
than that it should grow slabs which in turn have 
the power to grow other slabs? 
Is not the really wonderful thing the fact that 
it grows at all? 
The cactus is one of the most plastic of plants— 
educated up to this, perhaps, by the hardships 
and battles through which its ancestry has fought 
its way. 
A slip cut from a rose bush, for example, 
must be planted in carefully prepared ground of 
a suitable kind, at a certain time of the year, with 
regard to moisture and temperature—it must be 
watched and cared for until it takes root and 
begins for itself. Under continued cultivation, the 
rose bush has lost some of its ability to make its 
Own way. 
But the cactus, having come up from a line 
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