20 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
The " Sleeping Disease " of Tomatos. 
During the past two or three seasons a Tomato disease, far 
more destructive than any of the many diseases previously known 
as attacking the Tomato, has been noted in widely separated 
localities in Britain, although the headquarters of the disease 
appear to be in Guernsey and the Isle of Wight. As a rule, the 
plants are attacked while quite young, but the outward evidence 
of the disease does not usually manifest itself until the plant is 
full grown, or even not before the fruit is set. The first indica- 
tion that a plant is diseased is shown by the drooping of the 
leaves, which increases day by day, often accompanied by dis- 
coloration. If at this stage the root of the plant is split, the 
woody portion is seen to be of a dingy yellowish-brown colour, 
which becomes more marked after the root has been cut open 
for half a day. The above characters are the sure signs cf the 
presence of the disease, and all such plants should be removed 
and burnt at once, as they have reached the condition of being 
able to communicate the disease to adjacent healthy plants. 
The disease is caused by a minute fungus {FiLsarmm Lycopersici, 
Bacc.) whose life history is as follows. Certain resting-spores 
of the fungus, present in the soil in which the young Tomato 
roots are growing, germinate and give origin to very delicate 
hypha) or threads of mycelium : these hypha3, on coming in 
contact with the young Tomato rootlets, attack the outermost 
layers of living cells, and soon find their way into the vessels of 
the root, which they gradually fill with a weft of hypliiu which 
spreads to the adjoining elements of the vascular bundles, causing 
the discoloration already alluded to. By degrees the hypluu of 
the fungus gradually grow up the stem, following the course of 
the vascular system, ultimately passing into the leaves and the 
fruit. The progress of the fungus up the stem of the Tomato 
can be readily determined by the discoloration of tlic vascular 
system caused by the parasite. When a plant has been attacked 
for about three weeks, the lower portion of the stem is usually 
more or less covered with a very delicate white bloom : this 
appearance is due to the presence of numerous fruiting branches 
of the fungus which have pushed through the decaying tissues 
of the stem for the purpose of producing their conidia or repro- 
ductive bodies at the surface, where they arc readily dispersed 
