"The following account of a new enemy to the vine, translated from a periodical published at Ghent (the 'Flore,' edited by Louis van Houtte), may not be unacceptable to the readers of 'The Gardener.'

Phylloxera vastatrix (J. E. Planchon).-Female specimens and their eggs. a and a, antennæ ; b and b, horns or suckers; c, egg plainly visible in the body of the insect; d, the egg; f, winged form of the insect. All greatly magnified.

"In some localities of the south of France the vines are suffering from the ravages of a destructive insect, which has lately been noticed for the first time. M. E. A. Carrière has just published in the 'Revue Horticole' an extract from an article which M. J. E. Planchon contributed a short time ago to the 'Comptes-Rendus de l'Institut' (1868, p. 588). Here is the passage from the 'Revue':

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"I will here give a brief résumé of all I learnt about the habits of the Phylloxera vastatrix from a series of observations made on the spot, in three short visits to the south of France; also all I noticed with reference to the specimens which I kept in glass bottles during forty consecutive days.

"Its best-known form is that in which no trace of wings can be discovered. When the insect is about to lay its eggs (that is, in its adult female state), it forms a small ovoid mass, having its inferior surface flattened, its dorsal surface convex, being surrounded by a kind of fillet, which is very narrow when it touches the thoracic part of its body, which (formed by five rather indistinct rings) is hardly separated from its abdominal part of seven rings.

"Six rows of small blunt tubercles form a slight protuberance on the thoracic segments, and are found very faintly marked on the abdominal segments. The head is always concealed by the anterior

protuberance of the buckler; the antennæ are almost always inactive. The abdomen, often short and contracted, becomes elongated towards laying-time, and there can be easily seen one, two, or sometimes three eggs, in a more or less mature state.

"The egg sometimes retains its yellow colour for one, two, or three days after it has been laid; more often, however, it changes to a dullgrey hue. From five to eight days generally elapse before it is hatched, The duration of this period depends a good deal on the temperature. The quantity of eggs, and the rapidity with which they are produced, are probably determined by a variety of circumstances—the health of the insect, the quantity of nourishment it is able to obtain, the weather, and perhaps other causes. A female which had produced six eggs at 8 o'clock A.M. on the 20th of August, had fifteen on the 21st at 4 P.M.that is, she laid nine in thirty-two hours. Other females lay one, two, or three eggs in twenty-four hours. The maximum quantity is thirty in five days. The eggs are generally piled up near the mother without any apparent order, but she sometimes changes her position so as to scatter them all around her. They have a smooth surface, and adhere lightly to each other by means of a slimy matter which attaches to them.

"Hatching takes place through an irregular and often lateral rent in the egg, the empty and crumpled membrane being found among the other eggs in different stages of hatching.

"During the first period of their active life-two, three, four, or five days, as the case may be the insects are in an erratic state. They creep about as if they were seeking for a favourable situation. Their movements are more rapid than those of adults. They appear to inspect, as it were, with their antennæ the surface they travel over. The movements of the antennæ are generally alternative, and, if the comparison may be pardoned, are not unlike the two sticks of a blind man, which he uses to explore the ground he is about to tread.

"After a few days of this errant life, the young insects seem to fix upon a spot to settle in. Most frequently this is a fissure in the bark, of a vine, where their suckers can be easily plunged into the cellular tissue, full of saccharine matter. If you make a fresh wound on the root by cutting off a little piece of the bark, you may see the pucerons range themselves in rows around the wound, and, once fixed, they apply to the root their antennæ, which appear like two small divergent horns. At this period of their life, about the 13th or 14th day after their birth, they are more or less sedentary; but they change their places if a new wound is made on the root, which promises a fresh supply of food.

"What sense is this which directs these subterraneous pucerons towards the place which is most suitable for them? It cannot be sight, as their eyes are merely coloured spots, and they creep as if they were blind. It cannot be hearing, because they seek no prey but a vegetable tissue. It is probably the sense of smelling; and one may well ask if the nuclei which appear enshrined in the last articulations of the antennæ are not the organs of this function, the seat of which has been so much disputed? Among these non-adult insects, attached by their suckers to the vine-root, are seen, here and there, some of middle size. Their colour is a deeper orange, the abdomen shorter and more squarely formed. These individuals are more sedentary than the others. I have sometimes imagined they might be wingless (apterous) males of the species; but as nothing has happened to confirm this very problematical hypothesis, and as I have seen undoubted females much resembling these examples in colour and form, I incline to the belief that there are no sexual differences among them. A kind of double moult precedes the adult state. The first takes place shortly after birth, the second after laying-time. Some uncertainty, however, hangs over the number of these changes, as the cast-off skins are often found mixed up with groups of pucerons of different ages, and it is difficult to distinguish them. On the morbid tuberosities of the fibrous vine-roots, or on the offshoots of the roots, the pucerons (perhaps better nourished) seem to pass more quickly through the different phases I have described; but, excepting that their colour is paler, they present no marked difference.

"The winged form of the Phylloxera might easily be taken for a separate species. The rare specimens which I have seen have all come from the pucerons nourished on the newly-attacked vineradicles. In their infant (or it might be called their larva) state they resemble those which I have suggested may be males, but the buckler soon becomes more strongly marked than in these last; and a kind of band seems distinctly to define the separation between this and the abdomen. The sheaths of the wings, triangular-shaped and of a greyish colour, appear on both sides of the buckler. It is easy to predict the advent of a winged insect from this chrysalis. When one of these nymphæ is seen to quit its place and to crawl over the root, or up the side of the bottle where it may have been put, its transformation is near. Soon, instead of a sort of pupa, a beautiful little fly appears, whose two pairs of wings, crossed horizontally, are much larger than its body.

"It is impossible to doubt the identity of this insect with the puceron which formed one of the swarm on the vine-root. The

details of the structure of certain organs-the antennæ, claws, tarsi, and suckers-establish their identity.

"The horizontal position of the wings completely distinguishes the Phylloxera from the true aphis, whose wings are always more or less inclined upwards. The two larger wings, obliquely oboval and cuneiform, have a lineal areole on the larger basilary half of their outer edge; and this is enclosed in an interior nervure," which answers, I suppose, to the radial muscle. One single oblique nervure (or corneous division) is detached from this last, and reaches to the inner edge. Two other lines start from the end of the wing, and, becoming narrower as they proceed, advance towards the oblique nervure, but end before reaching it. These are not, perhaps, nervures, but rather folds, for I have observed them absent.

"The inferior wings, both narrower and much shorter, have a marginal nervure running from the base to the middle, but it loses itself in a gentle protuberance, which the wing shows in this place; a radial nervure runs parallel to the first, and disappears before it reaches the same spot.

“The eyes, black and (relatively) very large, are irregularly globular, with marked conical nipples; their surface is granular, but a pointed depression is observed in the centre of each glandule. A round eye-shaped spot occupies the centre of the forehead.

"Among fifteen winged specimens of the Phylloxera which have come under my notice, not one has presented any sexual difference. Almost all of them laid two or three eggs, and their death (which happened soon after) may have been caused by their imprisonment in the bottles. Their eggs resembled those of the wingless Phylloxera, and though they were only two or three in number, they completely filled the abdomen of the mother. They were easily seen by placing the insect under the microscope. I do not know how long the eggs remain before they are hatched, or if they always produce the winged form of the insect. It is probable that these winged individuals serve for the transportation of this insect plague to a distance; not that their wings would serve them for a rapid flight-they are too inactive, they move them very little, and in rising from the ground their horizontal position is preserved. My observations were, however, made under very unfavourable conditions, the insect being in a state of captivity; but I suppose that even in the natural state the wind is the principal agent for the dispersion of the Phylloxera, as it is for many of the insect tribe. In any case, the discovery of this form of the Phylloxera provided with wings, and evidently fitted for an aerial life, is sufficient to explain the hitherto embarrassing fact of the rapid

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spread of the vine-plagues. As to the spread of the disease from one vine to another, the wingless pucerons may suffice for this, as, grouped in great numbers about the lower part of unhealthy vinestems, they might easily attack the vines nearest them, even if they be healthy. It may be asked, in what manner these insects manage to travel from one vine-stock to another, and how they contrive to reach the fibrous roots of the newly-attacked stocks? Do they burrow under the soil; or do they not rather travel along the surface of the earth under cover of the darkness and coolness of night, and then, traversing the fissures in the bark, arrive in this manner at the extremities of the roots? This conjecture is a probable one, and the following experiment supports it:

"In a case 1 yard long I placed some garden soil from Montpellier, a place entirely free from the Phylloxera. In this earth I carefully laid some pieces of vine-cane infested with wingless pucerons. I placed a handglass over each cane, and slightly raised the glass on one side in order to allow the insect to creep out. At three centimetres' distance from the pieces of cane I put some fragments of root from a healthy vine, on which I had made fresh wounds. In twelve hours the following results were obtained: Three pucerons had found their way from one of the vine-canes to the nearest piece of vine-root. Some days after, twenty young pucerons occupied the same fragment. A few insects were to be found on the other fragments. One piece of root had attracted none, but the vine-cane nearest to it had very few insects upon it which were capable of changing their places. "A similar experiment has been made by M. Frédéric Leydier at the farm of Lancieux, near Sigondas (a part of the country already infested by the Phylloxera), and by another person near Sorgues. The results of these experiments have not been satisfactory; but this does not prove that, under other conditions, or with a greater amount of perseverance, they might not have been successful. It is fortunate that this new enemy to the vine attacks it (in the first instance) at the base of the stem, and not underground at the fibres. As it is, a thorough dressing of the bottom of the stem with coal-tar will probably prove an insurmountable obstacle to the progress of this destructive insect; but were the case otherwise, it would be very difficult to get down deep enough to reach an enemy so well protected by the depth of the soil.'” N.

The only remedy that has yet been discovered for this dreadful pest, is to root out the affected vines, remove all the soil they