ANGUILLULID^E. 
7 
The life dimensions noted for me by Dr. J. G. de Man in 1887, 
from measurement of specimens of T. devcistatrix taken from stem-sick 
Clover, sent me from Kent, are as follows:— 
Dr. de Man reported to me:—“ I found that both the male and 
female attain to a length of 1*5 mm.; the tail measures in both one- 
fifteenth to one-sixteenth of the whole length ; the oesophagus measures 
one-sixth to one-seventh of the whole length, and the spear in the head 
has a length of CkOlS mm. All these dimensions perfectly agree with 
the original description of Kuhn, so that these specimens positively are 
representatives of T. devastatrix .The eggs of T. devastatrix are 
oval, and are 0*07 to 0.08 mm. long.”—J. G. de Man. 
Males, females, larvae, and eggs may be found together in the 
infested shoots. One millimetre being the 25th part of an inch, it will 
therefore be seen by the above note that the largest size of these Tylenchi 
is little above the 25th part of an inch in length, and that the “ mouth- 
spear,” one of the portions that is necessary to make out clearly 
for identification of species, is only visible at all when enormously 
magnified. Under these circumstances, although I examine carefully 
for Eelworm presence, I have never yet reported Tylenchus devastatrix 
as quite certainly present, without first submitting my identification to 
one of the two distinguished experts, Dr. de Man or Dr. Ritzema Bos. 
Distribution. — We have, in the course of the three years in which 
this attack has been under special observation, found it in widely- 
separated localities, so that it may be considered as generally distributed. 
I have received specimens, in Clover suffering from “ stem-sickness,” 
from Playford, near Ipswich ; from a locality in Kent, “on a coomby 
soil between the Chalk and the Greensand ” ; from Woburn, in Bed¬ 
fordshire ; and Rothamstead, Herts (as above mentioned); and from 
Uphall, Linlithgowshire, in Scotland. Other specimens of attack were 
sent me, in which I found the deformed or “ stem-sick” growth, and 
also the Tylenchus with spear placed on a bulbous base; but as it is of 
considerable importance to record the Clover-attack without any pos¬ 
sibility of mistake, I have only in this paper noticed the cases in 
which I had the benefit of skilled identification, or confirmation of my 
own observations. 
Method of Prevention and Remedy. 
Tylenchus devastatrix, or the “ Stem Eelworm,” as it may con¬ 
veniently be called, infests many kinds of crop and weed plants, 
and can pass from one to the other ; consequently rotation of crops is 
one point to be considered in the matter of prevention. 
Some of the field crops most subject to attack are Oats, Rye, 
Clover, Teazels, and Buckwheat; Onions also are very liable to it, and 
there is also a Potato-sickness caused by Tylenchus devastatrix. This new 
form of attack was observed by Dr. Kuhn in Germany, and also by Dr. 
