Osborne^ on the Wheat Plant. 
119 
terns of vascular tubes is so produced, as to send tlie one 
more simple system to the roots, another, with all the 
varieties of structure, to the leaves. 
With regard to the leaf, I believe the chief office of the 
spiral fibre is to support and give general strength. It will 
be seen here to anastomose, small branches passing from one 
main vessel of this fibre through the cellular substance, t6 
unite with another similar vessel. 1 have never detected 
this, as existing in the case of the scalariform vessels of the 
roots. These I believe to be also formed for the direct pur- 
pose of strengthening the structure with which they are 
incorporated. They become a species of elastic skeleton to 
an organized body, where every purpose requires that it 
should at the same time be supple and yet strong. The only 
anastomosis to be seen in these vascular fibres of the roots, is 
where one of them gives off a bundle to a lateral root. 
Although I have succeeded, by the use of the air-pump, in 
forcing a little coloured fluid between these fibres and the 
cell-texture which invests them, I can introduce nothing into 
their own substance. 
When I look at what a wheat root has to do ; how it has 
to force its way and introduce its lateral branches through all 
manner of crevices, and amongst all kinds of material in the 
soil, I am struck with wonder at the beauty of the con- 
trivances by which the spongules or capsules, constructed of 
highly elastic material, can float their onward way; con- 
solidating as they grow, and having within them the growing 
organism of a scaffolding sufficiently strong to bear up, in 
its deposited order, all the necessary structure ; and yet 
sufficiently pliable, to follow that structure in any course it 
may be compelled to take, however tortuous. 
By growing the wheat plant over spring water, and then 
submitting the leaves to a continued boiling in nitric acid, 
very beautiful preparations of the pitted tubes and the rings 
of the annular fibre are obtained. If there are casts in silica 
of the original vessels the silice must be taken up from the 
water. 
I will only now add, that I will with pleasure give any 
further explanation upon any point on which I have now 
touched, and any information as to the manner in which I 
have made my experiments. I believe a close study of the 
growth of plants, by means of the perfect instruments we now 
possess, if pursued, not by mere amateui^s like myself, but by 
men of real scientific knowledge, would lead to most usefill 
results. Science has done a good deal in teaching us how best 
to enrich our soils. Histology may yet throw valuable light on 
