EARLY GROWTH. 39 
usually more slender than the body from which 
they proceed, are called root fibres. It is these 
fibres, or rootlets, which penetrate the ground 
by insinuating their extreme points into the 
earthy interstices, displacing, by expansion, suffi- 
cient earth to provide room for themselves. The 
collecting apparatus, however, for gathering what 
nourishment the plantlet requires from the soil, 
is supplied, not immediately by the root or root 
fibres, but by a beautiful series of delicate root 
hairs. These grow out from both the main root 
and the rootlets in large numbers, and being long, 
tubular bodies, though very minute, they absorb 
moisture from the surrounding earth by means of 
that, as yet unexplained, foree—capillary attrac- 
tion. The moisture thus extracted from the 
earth holds in solution those chemical substances 
which—by a beautiful and marvellous process 
of assimilation—minister to the growth of the 
embryo plant, and promote its stability. 
The plumule, meanwhile, has been forcing its 
way to the surface of the ground, there to unfold 
a couple of tiny incipient leaves. In some plants 
the ascending plumule carries the cotyledons to the 
