IV 
PREFACE. 
The careful experiments as to the cause of true Clover 
“Sickness” (as distinguished from disease caused by fungus; 
maggots at the root; decay at the top; non-thriving from state 
of soil, &c.) have proved this disease to be so constantly connected 
with presence of a special kind of “ Eelworm ” as to make it 
appear that this Tylenchus devastatrix is the cause of this so- 
called “Sickness.” Reports of observations regarding this Eel- 
worm are given under the heads of “ Clover Sickness,” and of 
“ Tulip-root ” in Oats, and show, amongst other points, the 
facility with which plants of kinds liable to infestation may 
receive it by being sown over infested remains. 
The proof of the migration of Hop Aphis, to and fro, in 
spring and autumn, between Hop and Plum of various kinds, is 
very important to Hop growers, because this point, although 
commonly believed to be the case, was not so certainly known 
before, especially with regard to the autumn migration; and the 
new observations made by Prof. Riley whilst in England, on this 
latter point, open up one certain way towards lessening amount 
of Hop Aphis. 
The means of prevention of the great amount of injury 
caused to orchard foliage in the spring by the “Looper ” cater¬ 
pillars of the “Winter Moth” have been further experimented 
with, and the simple measure of putting a band of sticky 
material round the base of the trees, in previously infested 
orchards (so as to prevent the wingless female moths creeping 
up to lay their eggs in early winter), has been confirmed as 
successful.* 
Various communications have been placed in my hands 
regarding the Sparrow nuisance, but I have not entered on the 
subject here, as I trust very soon to be able to bring forward the 
special points calling for grave consideration more effectually 
than I could do in my own Report. 
Other details and notes of attack are given under their 
respective headings, and, together with these, I have expressed 
my thanks and acknowledgments to the kind contributors to 
* Whilst this report was passing through press I received information from 
Mr. Robert Mercer, of Rodmersham House, near Sittingbourne, regarding the 
above point:—“I have followed your advice in using Davidson’s Composition, and 
all through the month of November the belt of mixture at the bottom of the trees 
was almost covered with the moths.” 
