A Vine-land correspondent says: "I have taken the liberty to send you, by express (paid), a paper package that contains a specimen of what may perhaps be called the club-root in a greenhouse tomato-plant; the cause of which I would like to ascertain, and I know of no one more likely to be able to give information on such a subject or more likely to be interested in its investigation than yourself.

" We have raised winter tomatoes successfully several years in our greenhouses, the only serious difficulty we have had to contend with being mildew. Last year there was some of the club-root in the houses; this year there is a great abundance of it. Several queries have arisen in my mind in relation to this disease, whether the excessive mildew this year may have been the cause of the disease, or the disease the cause of the mildew; or whether the disease may be owing to too much or too little enriching, or to the kind of enriching; or whether the soil may not have been poisoned by growing in it the same kind of plant several years in succession; or whether an insect may have had something to do with it. The manure used has been principally stable manure, but, perhaps, not enough of it, or not sufficiently rotted. The soil is naturally a sandy loam.

" We raise, in the same houses, Black Hamburgh grapes, the roots of which run below those of the tomatoes.

"Any information as to the probable cause and the possible remedy of the disease referred to will be very thankfully received".

[The roots were knotted like strings of beads about the size of peas. There is no relation to club root, which is the work of a fungus. It is the work of an insect, and they are indeed galls. By cutting across the excresences, squeezing a little, and examining with a pocket lens, a number of transparent eggs about the size of pin heads are seen to have emerged. These eggs have of course to remain here till they hatch, become larvae and enter the pupa stage. It ought not to be difficult to destroy the whole race by taking out the roots of the tomatoes carefully some time before the creatures leave them, and burn. It would also be a benefit to remove as much earth as possible and replace with fresh.

From this letter and a large number of others we have received during the past few years it is surprising how many people try to get along without a pocket lens. Gall insects that operate on roots are very common, and in a large number of cases sent to us, if people would only cut open and examine, they would see the "cause" for themselves. - Ed. G. M].