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THE POPULAR SCIENCE MONTHLY.

ing it in check in this country. This mite (Tyroglyphus phylloxeræ Planchon and Riley, Fig. 8) belongs to the same genus as the cheese and meal mites (T. zivo, Linn.), and the species (T. entomophagus Laboulbène) which infests preserved insects, and is such a pest in cabinets.

Fig. 8.

Phylloxera Mite.a, dorsal; b, ventral view of female; c, mouth-parts magnified; d, f, g, h, forms of tarsal appendages; e, veutral tubercles of male.

Direct Remedies.—The leaf-lice, which do not play such an important part in the disease as was at first supposed, may be controlled with sufficient ease by a little care in destroying the first galls which appear, and in pruning and destroying the terminal growth of infested vines later in the season. The root-lice are not so easily reached. As the effort will be according to the exigency, we may very naturally look to France for a direct remedy, if ever one be discovered. But, of all the innumerable plans, patented or non-patented, that have been proposed, of all the many substances that have been experimented with, under the stimulus of a large national reward, no remedy has yet been discovered which gives entire satisfaction, or is applicable to all conditions of soil. Nor is it likely that such a remedy ever will be discovered. A large majority of the remedies proposed, such as the planting of Madia saliva among the vines, or inoculating them with the essence of Eucalyptus globulus, are, upon their face, absurd. These we will pass by, and briefly mention only those which have been more or less productive of good.

Submersion, where practicable, and where it is total and sufficiently prolonged, is a perfect remedy. This is what even the closet-student might expect, as he finds that excessive moisture is very disastrous to the lice. M. Louis Foucon, of Graveson (Bouches-du-Rhône), France, has abundantly proved its efficacy, and has, by means of it, totally annihilated the insect from his vineyard, which was suffering from it four years ago. From his experience we may draw the following conclusions: 1. The best season to submerge is in autumn (September and October), when the lice are yet active, and the vines have ceased growing. Submergence for twenty-five to thirty days, at this season, will generally rout the lice. 2. A submergence of forty to fifty days