INVESTIGATIONS ON THE NARCISSUS DISEASE. 53 
stages of development and in great numbers in the inoculated bulbs, 
had travelled down from the neck along the fleshy scales and entered 
the basal plate, and in doing so had left the brown stain so character- 
istic of a diseased bulb. There was not a single instance in the dozen 
or so bulbs inoculated which did not show these characteristics in a 
marked degree (fig. 22, A). The bulbs in the control experiment were 
perfectly healthy (fig. 22, B). 
Another series of inoculation experiments was arranged in the 
greenhouse. Healthy bulbs were grown in pots, and on February 22, 
when the flowers were just bursting into bloom, the plants were inocu- 
lated in the following ways : — 
(a) Eelworms introduced into the wound left from picking off the 
undeveloped flowers, 
(b) Eelworms pricked into the leaves 4 inches above the neck, and 
(c) Eelworms placed on uninjured leaves at the same distance 
from the neck ; 
(d) Used as a control. 
In less than a week evidence of disease was apparent. In (a) the 
flower stalk rotted and showed a wrinkled, marbled appearance ; it 
also became very deformed, swollen, and angular, as hg. 23 clearly 
shows. The same plant is shown in fig. 24, A. In (b) and (c) 
(fig. 24, B, C) the leaves soon lost their rigidity and fell over the sides 
of the pots in all directions, and showed the same wrinkled and 
distorted appearance as in the inoculated flower stem. Fig. 25 
shows the invasion at (a) of the uninjured leaf referred to in (c) above, 
by the eelworms, with a healthy leaf for comparison. On April 20, 
eight weeks after inoculation, some of the plants were lifted and cut. 
The photographs (figs. 26 and 27) demonstrate that the eelworms had 
not been inactive. Infection occurred in all cases where inoculation 
was attempted, and none of the control plants showed the disease. 
Tylenchus devastatrix was first described by Julius Kuhn in 1858 
as being the cause of a disease in Dipsacus Fullonum, the Fuller's 
Teasel, under the name Anguillula dipsaci ; but as he afterwards 
found that the same eelworm could attack oats, buckwheat, and other 
plants, he considered the name Anguillula dipsaci too restricted, and, 
disregarding the customary rules of priority, changed it to Anguillula 
devastatrix. Bastian, who' did important work on the classification 
of eelworms about i860, incorporated Anguillula devastatrix with 
several other eelworms in the new genus Tylenchus, and the eelworm 
with which we are now dealing became known as Tylenchus devasta- 
trix Kuhn. In 1881 Prillieux worked on the eelworm malady of 
Hyacinths. To this eelworm he gave the name of Tylenchus hyacinthus, 
while in 1883 Beyerinck published a paper on the eelworm malady 
of Onions, which at that time was spreading rapidly throughout 
Holland, and which he attributed to Tylenchus allii. 
In 1888 Ritzema Bos, one of our foremost Nematodologists, 
definitely proved that Tylenchus hyacinthus, Tylenchus allii, and 
Tylenchus devastatrix were one and the same species. The same 
