16 THE LIFE-HISTORY OF A FERN 
where they ramify and extend upwards to the extreme tips and margins. 
On the other hand, strands of vascular tissue derived from the leaf-bases 
extend towards the tips of the roots, and laterally into their branchlets. 
The Vascular System is thus a connected conducting-system throughout 
the plant. It is embedded in softer parenchymatous tissues, which serve 
Nephrodinm Filix-mas, Rich. A, stock in longitudinal section; 7, the apex; sé, the 
stem; 6, the leaf-stalks ; 4’, one of the still foldecl leaves ; g, vascular strands. 2, leaf- 
stalk bearing at & a bud with root at w, and several leaves. C, a similar leaf-stalk cut 
longitudinally, bearing bud, /, with root, w. D, stock from which the leaves have been 
cut away to their bases, leaving only those of the terminal bud. The spaces between the 
leaves are filled with numerous routs, zw, w’. A, stock from which the rind has been 
removed to show the vascular network, x. 7, a mesh of the network enlarged, showiuy 
the strands which pass out into the leaves. (After Sachs.) 
various purposes in the different {parts: .thus in the young root they may 
be absorbent, or serve to hand on the fluids absorbed to the conducting 
system: in the stem they may serve the purpose of storage of reserve 
materials, while in the leaf the parenchyma carries out the function of 
photosynthesis, together with the passing on of the supply thus acquired 
to the conducting-system. The parts exposed to the air are covered by 
