314 PHYLLOXERA. VASTATRIX, OR 
so. It is, however, very certain that the effectiveness 
of the remedy will not merely depend upon the nature 
and efficacy of the substance employed ; but the mode 
of application and the time at which it is used will also 
always be of very great importance. The substances 
capable of destroying these insects are very numerous > 
but, in order to produce beneficial results, care must be 
taken that they are not injurious to the plant, and 
that they can penetrate into the soil easily, to a depth 
of from sixteen to nineteen inches, so as to reach the 
insects beneath. And here comes the real difficulty. 
Applications capable of destroying the insect without 
hurting the vine, are what those persons who are 
seeking a remedy for the disease must endeavour 
especially to discover. Whilst awaiting that time 
when science shall have devised some means averting 
this evil, the Commission counsels vignerons and 
municipal bodies to follow the example given in 
l'Herault and la Gironde, where the diseased vines 
have been rooted up and the soil disinfected by the 
clearing off and burning of the surface. The Commis- 
sion also recommends the collecting together and 
burning of all gall-bearing leaves. 
These remedial measures, which are analogous to 
those used in the case of the cattle plague, have the 
advantage of destroying a great number of insects, 
which would otherwise increase and communicate the 
disease to the surrounding vines. Applied in time, and 
systematically conducted under intelligent supervision 
they may impede the progress of evil and even 
repel it. 
In instituting a prize of 20,000 francs (^800) for the 
discovery of a remedy for curing the diseased vines. 
