Osborne^ on the Wheat Plant. 
117 
and cyanide of potassium. It would be too great a trespass 
upon your patience to give all the various results of these 
experiments. The general conclusion at which I have arrived 
is, that, though what I call the epidermic plasm does absorb 
moisture from the soil, in fact requires moisture to preserve 
its elasticity, combining in the formative matter it secretes 
some of the matters presented to it, in whatever medium it 
may grow, still the great sources of plant health and strength 
are obtained by means of the capsules or spongioles, the 
termini of every root and rootlet, and also by the absorbent 
cells ever found at the extremities of the numberless suckers ; 
for it is at these points that I find the cell- structure ever 
greedily taking in whatever of foreign matter I have succeeded 
in introducing into the media in which 1 have grown the 
plants. The action of anything placed in the medium in 
which plants grow, which is injurious to them, is at once 
shown by its action upon their roots and lateral processes, the 
capsules losing many of the characteristics of healthy action. 
It is a curious feature in these experiments that, although 
deep roots give a great deal of green leaf to the plant, yet 
when pernicious substances or fluids stint the roots by injury 
to the spongioles, for a time there is nevertheless an active 
leaf-growth. I am also strongly impressed with the belief, 
that the hairs with which the surface of the leaves of cereals 
are so regularly studded, receive from the atmosphere and 
introduce into the leaf-structure those atmospheric elements 
so necessary to its growth. I have never yet traced any 
circulation in any part of the plants on which I have experi- 
mented, but I have seen active molecules at the base of some 
of these hairs, and in one instance crystals of the character 
of oxalate of lime. 
When the spongioles are poisoned or mechanically injured, 
the internal cells of the root are imperfectly developed, they 
appear as mere quadrangular masses of granular matter 
floated or imbedded in hyaline plasm, with few aggregations 
of the matter, and very few nuclei, these being irregularly 
formed. Distilled water is an easy means of proving this fact, 
a rather strong solution of alum, also soil mixed with the 
bronze powder, which latter binds the soil into a hard mass. 
There can be no doubt but that the plant requires not only 
certain chemical constituents to secure its health, but that 
these must be offered to it, when growing in a medium, 
allowing the utmost freedom to the capsules of the roots, 
rootlets, and to the suckers. I am satisfied a highly pul- 
verized poor soil would grow better plants than a close, hard, 
tenacious soil, however fertilised. 
