120 
OsBoiiNE_, on the Wheat Plant. 
the processes^ by which the plant takes up for itself the food 
we offer it. A close study of the mechanism employed by 
nature_, will show to us in what form_, and under what con- 
ditions^ fertilizing matters can be best applied,, so as to secure 
their most perfect assimilation. 
Allow me also to say that^ in my opinion^ no student of 
animal physiology can pursue this course of research without 
being struck at every step with the very strong analogy 
existing between the development of vegetable and animal 
structure. I will not trust myself to enter into this subject 
farther than to declare, that every day^s work on vegetable 
structure has given to me a new interest in every page I read 
which relates to the structure of animal. I cannot but think 
we are approaching a time when the microscope, in the hands 
of men of science, will prove in these two fields of God's 
wonder working, the existence of a strictly analogous 
principle, developing and sustaining animal and vegetable 
life, with only that much of difi*erence in the processes which 
the obvious purposes of the two existences would lead one to 
expect. 
Since I have put to paper what I have now read to you, I 
have made a few preparations which I think it may be in- 
teresting to describe before I show them. I have stated my 
belief, that the roots of the wheat take in nourishment for 
the plant from the medium in which they grow, by means of 
their capsules, and those on their rootlets. I should have 
perhaps better expressed what I mean if I had said at these 
points of their structure. Wishing to make some experi- 
ments on the action of poisons, I grew a small crop in a strong 
solution of prussic acid with cyanuret of potash added to it, 
I found this gave a very vigorous growth to roots and leaves. 
J ust as the root had acquired about four inches of length I 
applied my colouring matter to the fluid in which they grew ; 
I wished to see whether this would be taken up anywhere but 
at the above points. I will show you that it was not, that the 
parenchyma or outer cell-texture is colourless, that the 
capsule-cells are strongly painted; that as they have pushed 
on nothing has been left in the matured cells coloured but 
very small nuclei, excepting only along the whole course of 
the vascular bundle ; here what I call the pith-tubes will be 
seen to have imbibed the pigment, and it can be traced 
along their whole course, i.e., along the whole course of the 
growth made since the solution was coloured. 
There is another curious and, to me, most interesting result 
from this experiment. I have said, I believed the nuclei to 
be aggregations of the formative matter in plasm, I have also 
