oS a ee 
ACADEMY OF: SCIENCES. 18] 
found, the size of the patches becoming larger as they were found nearer the 
surface. They were confined exclusively to a single longitudinal crack in the 
bark, at least from where the roots divided, about two feet beneath the sur- 
face. As before stated, they were found in patches, no insects being seen in 
the spaces between the patches. It was evident the crack in the bark of the 
root hid offered a route by which the insect was gradually making its way 
down on the root. The patches undoubtedly indicated the stages by which 
the insect proceeded downwards, one insect from above passing over the in- 
tervening space and establishing a new colony, from which pioneers again 
started out to descend still lower. From the few insects found in the lowest 
patch, it is probable that this portion of the root had but just been attacked, 
and that not more than one generation had been born there. On some small 
roots that were given off about a foot from the surface, I found but one insect, 
and that near the main root. The soil of the vineyard was a gray clay, con- 
taining a considerable quantity of sand. It was derived from the disintegra- 
tion of voleanic sedimentary rocks, and as it had been well ploughed and 
harrowed, it was quite fine and dusty. Under these circumstances, it is 
quite certain that the insect would not reach the roots of the vine through 
cracks and holes in the ground, as it is stated to do in France. Here there 
can be no doubt but that the migrations of the insect took place down the 
cracks in the outer bark, which not only afforded it a road, but also enabled 
it to introduce its sucker into the softer cambium, from wnich it derives its 
nourishment, and which it could not have reached ‘through the whole thick- 
ness of the bark. 
The fact of the infection of an apparently healthy vine, offers a serious 
prospect for the future wine prospects of the State, as it is impossible to say 
to what extent the disease already exists. It is probable that its effects only 
become manifest after it has already existed on a vine perhaps for years, and 
I think it likely that it will be found far more widespread than is now antici- 
pated. Ihave, however, taken measures to ascertain this point, and I trust 
these remarks may call the attention of our wine-growers to the subject, and 
lead them to look for the insect amongst their apparently healthy vines. My 
own opinion is, that when a vine has once been attacked by the insect, it is 
merely a question of time as to when it will be killed, and the facts above 
stated show how hopeless it is to expect to be able to eradicate it when once 
itis established. In order to do this, we should have to expose the roots of 
the plant, and apply our remedies below the lowest point where the insect 
has penetrated. This is simply impossible. The only chance I see for suc- 
cessfully meeting the disease is, to endeavor to prevent its attacking vines 
that are already healthy, and I think this can most likely be effected in a man- 
ner that may not involve too much expense. There are two considerations in 
the history of the insect, which lead me to hope that this may be done. In 
the first place, I believe that at least in loose, pliable soil, that is kept well 
cultivated, the insect can only find access to the roots by crawling down the 
cracks in the bark, or in the crevices that are generally found about the root 
at the surface of the ground. I think it probable that some application, such 
as tar or train oil, that might be distasteful to the insect, might prevent its 
crawling down the stem; and surrounding the stem for a fewinches with fine, 
