112 ONIONS. 
‘se crispent,” Ep.], ‘and the scales acquire an extraordinary size. 
At the part where the Helworms are to be found in great numbers, 
the leaf or the scale shows the greatest thickness; this is not the 
same everywhere.” *—(J. R. B.) 
The bulbs figured were lifted (as well as other Helworm-sick 
specimens) from one of the Onion beds in my garden in the middle of 
July; the one figured at p. 107 was about three and a quarter inches 
across by a little more than two inches high. On taking one of the 
thickened diseased outer scales from this bulb, I found that the skin 
on the inner side of the scale peeled away in a film at a touch, and 
between this and the skin of the outer side the substance of the scale 
was decomposed, or, perhaps I should say, disintegrated, into a mere 
collection of cells, to a great extent separated from each other. This 
mass was dead, but not yet decayed, and in it I found some Kelworms; 
but in a scale underneath it, in which some life was still remaining, I 
found Eelworms of all ages, absolutely swarming, and their eggs also 
in great numbers. 
In both of these nearly-grown Onions, which I carefully examined, 
I found yellow crumbly matter under the edge of the swelled cracked- 
back scales, or near the base of the bulbs, just such as we find inside 
the hollow parts of ‘‘ Tulip-rooted” Oats or of ‘‘ Stem-sick”’ Clover. 
Having been able to observe the shortened swelled growth of the 
young growing plants, and also the widened growth of the diseased 
bulbs with their thickened scales cracked open by the enlarged growth 
of the inner ones splitting the outer ones aside to make room for them, 
I was desirous to see also the appearance of the commencement of 
disease, when beginning at the very germination of the seed. The 
process of this (see work by Dr. Ritzema Bos, previously cited, p. 129) 
is that when, in germination, the spermoderm (skin of the seed) breaks 
open, then the Eelworms, which are in the soil, obtain entrance into 
the cotyledon (the first leaf of the germinating plant) almost before it 
has sprouted. Consequently on this attack, the cotyledon at once 
assumes a deformed growth, such as swelling in different parts, or 
with unnatural bends; also whilst in the case of the little seedling 
Onion sprouting naturally, the cotyledon usually carries the empty 
seed husk on its top, in the case of the infested seedlings this cotyledon 
or seed-leaf may be so much swelled that the seed-husk is detached, 
and the young plant comes through the soil without it. 
On September 5th, in order to watch this myself, I got my gardener 
to fairly fill a flower-pot, ten inches across, with earth, on which we 
* Without entering on elaborate botanical explanation, it may be of use to 
mention that parenchyma is the term given where the cells of the tissue are 
roundish or elliptical; whilst the fibro-vascular bundles consist of woody tissue, 
and spiral or much elongated vessels. 
