ANOUILLULIM. 
5 
the specimens inspected) when the winter was passing away. The 
above gives the history of the Woburn attack, so far as I know it up 
to present date. 
With regard to that at Rothamstead .— About the end of March and 
onwards I had much communication with Mr. John Willis, of Har- 
penden, regarding Clover-disease in the neighbourhood of Harpenden. 
In the plants more particularly submitted to me for examination from 
a field of Red Clover belonging to Sir John Lawes at Rothamstead, 
the attack was similar, apparently, to that mentioned on p. 4 as 
occurring at Woburn; and though various kinds of Weevil, and of 
Gnat-midge Maggots, Millepedes, &c., were present in the earth at the 
roots, there did not appear to me to be any reason to consider that 
the diseased state of the crop was caused by anything but (as at 
Woburn) by the Tylenchus devastatrix. 
Some of these plants I also forwarded to Dr. Ritzema Bos, and on 
April 22nd, that is, four days after I had been favoured by him with 
the report on the Woburn specimens, he reported on these from 
Rothamstead to me as follows :— 
“I have examined your Clover-plants from the fields of Sir John 
Lawes at Rothamstead, and I have found in them the same organisms 
as in those sent to me by Mr. Francis E. Fraser. I saw the buds and 
the branches swollen up, but the latter remained very short, and the 
leaves remained little. In some of the plants sent by you, the roots 
were dying, but without any attack by insects, worms, or other 
animalcules at the outside of the roots. In some other plants the 
roots remained healthy, were recovering, and putting out little shoots. 
In the swollen shoots and buds I found Tylenchus devastatrix in large 
numbers, and also their eggs ; in the dying parts also some Rhabditis 
and Cephalobus species, but these in small numbers.” 
“Without any doubt, the Clover-sickness of the plants you were 
good enough to address to me is caused by Tylenchus devastatrix: 
I conclude this from the large number of Tylenchus which I found in 
the diseased plants, and from the general appearance of the Clover- 
plants.”—J. R. B. 
It is not at all unusual to find various kinds of Eelworms feeding 
in the withering or decaying parts of plants suffering from Tylenchus 
attack, although these other species, as far as observations go at 
present, never cause the Clover “stem-sickness.” 
One main point of distinction of these Nematodes , or “thread¬ 
worms,” is the form of the oesophagus, or gullet, by which food is 
sucked into the wormlet. In some cases the mouth-cavity is furnished 
with a long process, called a spear, and in the Tylenchi this spear is 
placed on a trilobed bulbous base. The figure at the head of this 
paper gives some idea of a few of the forms of the mouth-extremity of 
different kinds of Nematodes. 
