Oct. 2 2, 1 874] 



NATURE 



505 



tion of this alarming scourge, which has destroyed the 

 produce of so many of the fairest vineyards of the south- 

 east of France. 



It is a matter of no difficulty to master the history of 

 the new disease produced by the Pliylloxera, and to trace 

 its growth from the earliest beginnings. The first 

 definite signs of the invasion of the parasite were observed 

 in the year 1S65, at a spot (plainly marked in the maps 

 annexed to the report of M. Duclaux, and now copied for 

 our readers) on the plateau of Pujaut, near Roquemaure, 

 in the neighbourhood of Avignon, and in the department 

 of the Gard, on the west bank of the river Rhone. Though 

 in this year it attracted but little attention, in 1S66 it 

 descended rapidly from the plateau to the outskirts of the 

 village of Roquemaure, and also appeared in several spots 

 in the departments of Vaucluse and the Bouches du 

 Rhone, both lying on the east side of the river-valley. 

 It was the owner of a vineyard in this latter department, 

 a M. Delorme, of Aries, who was the first to recognise the 

 disease, while still in the birth, as a new disease, and to 

 have the presentiment of the disasters which would follow 

 in its train. At a later period a commission of the Society 

 of Agriculture of the Herault visited by request the vine- 

 yards around Saint-Ri^my, and a member of that com- 

 mission, M. Planchon, discovered that the cause of the 

 vine-disease was an insect " destined to be the subject of 

 so much discussion, and to become the source of so much 

 misery." It was he who afterwards gave the parasite the 

 name which it has since borne everywhere — Phylloxera 

 vastatrix. 



Before proceeding to describe the ravages of the insect 

 and the manner in which it ultimately causes the death 

 of the vine, it will be well to show the progressive 

 extension of the disease itself over the country adjacent 

 to the Rhone valley and lying inland to the north of the 

 Gulf of Lyons. M. Duclaux has shown us, in his series 

 of maps annexed to his report, the progress of the disease 

 between the years 1865 and 1S72, and marks it as gra- 

 dually extending from the little spot first attacked in the 

 neighbourhood of Avignon till in the last of those years 

 it included the whole country between Valence on the 

 north and Marseilles on the south, while westwards and 

 eastwards it extended to Montpellier and Aix respec- 

 tively, thus covering, roughly speaking, nearly four de- 

 partments, viz., the Gard, the Drome, Vaucluse, and 

 Bouches du Rhone. We are told in the memoir of M. 

 Louis Faucon, also presented to the Academy of Sciences, 

 and embracing a later period than that of M. Duclaux, 

 that the disease extended to an alarming degree in the 

 year 1873, at the same or a greater progressive rate, 

 and had established itself in that year in no less than 

 twelve deparjments of South-east France, having spread 

 into the Ardeche, the Basses-Alpes, Var, Iscre, Herault, 

 and even reaching so far as the Gironde and the two 

 Charentes. 



We may gain a more precise idea than can be afforded 

 by a mere observation of the geographical extension of 

 the disease, of the disastrous nature of the ravages of the 

 Phylloxera, by the examination of some of the statistics 

 of the grape-crop in successive years in some of the de- 

 partments attacked. Thus, in the department of Vaucluse, 

 where the disease showed itself in 1866, there were in 

 1869, according to the results obtained by the depart- 

 mental commission instituted at Avignon to observe on 

 the new vine-disease, 6,000 hectares absolutely dead or 

 dying, and a much larger number already attacked, which 

 have since succumbed to the parasite. Out of the 30,000 

 hectares of vineyard comprised in this department, 25,000, 

 or five-sixths of the total area, have been destroyed. In 

 the Gard, where the vine fiourishcs better than in the 

 above-mentioned department, the ravages of the disease 

 are yet most terrible, for in iS7i,in the arrondissement of 

 Uzfes, but one-half of the average crop was produced, and 

 in the arrondissement of Nismcs, a tenth part of the crop 



was destroyed. These proportions, moreover, have in- 

 creased since that year. 



If we ex^imine the mischief done in the less extended 

 areas of the communes, we shall obtain a still clearer idea 

 of the rapid spread of the disease : — 



Commune of Graveson. 

 1865-66-67 mean crop 10,000 hectolitres 



1868 „ 5,500 „ 



1869 „ 2,200 „ 



1870 „ 400 „ 



1871 „ 250 „ 



1872 „ 100 „ 

 'S73 „ 50 „ 



In the commune of Maillanne the crop in 1868 was 

 only 40 per cent, of the average of the three preceding 

 years, while in 1S69 it was only 10 per cent. In the com- 

 mune of Eyragues the crop in 186S was about 33 per cent, 

 of the average of the three preceding years, and in 1869 

 there was a further falling otf of about 10 per cent. In 

 1870 the crop in the three above-named communes was 

 almost entirely destroyed. From instances such as these, 

 fairly selected from many others equally tragic in their 

 stern figures, we may form some idea of the magnitude 

 of the disaster. Indeed, it is difficult to see, so rapid is 

 the extension of the disease, how, unless some potent and 

 effective remedy can be soon applied, any vine-bearing 

 district in France can escape the visitation of the 

 Pliylloxera. 



Though there can be no doubt that the Phylloxera is 

 the cause of the new vine-disease, this conviction was by 

 no means arrived at at once, nor without considerable 

 doubts being thrown upon it by those whose better judg- 

 ment was obscured by the confusion of concomitant phe- 

 nomena such as drought, cold, and impoverishment of 

 the soil with the real source of malady of which they 

 were the companions. Others, even now, hold that the 

 Phylloxera is the effect and not the cause of the disease ; 

 this idea M. Faucon dissipates satisfactorily in his treatise 

 by the following reasoning : — .A vine is watched which is 

 in a perfect state of health and vigour ; not a single para- 

 site is discovered in the ramifications of its roots. A day 

 comes when the destructive insect invades it— it resists 

 for some time ; the Phylloxera lays its eggs, multiplies 

 its numbers, and with them its attacks. The stem of the 

 vine begins to show signs of the disease, and if the roots 

 are laid bare, they may be observed to h.ive deteriorated 

 in some degree from their normal state. The multi- 

 plication of the insect continues, and assumes such 

 proportions as to form yellow spots of no small 

 size, the result of the close collection of a large 

 number of the insects, whose puncturings are so nume- 

 rous and so incessant that the roots can no longer 

 perform their proper function, the nutrition of the plant, 

 which, in consequence, falls into a most evident state of 

 sickliness, lingers on for some time, and eventually dier. 

 The Phylloxera takes its first food where it can get it 

 with the least difficulty. After it has exhausted the sur- 

 face rootlets, tender and succulent as they are, it attacks 

 others deeper down; then it spreads over ttie hardier roots, 

 till at last the prodigious increase of its family causes it to 

 overrun the whole radical system of the plant, and even 

 the part of the stock of the vine which is underground. 

 It abandons the exhausted plant when it is of no more 

 use to it, and its instinct turns its steps towards a new 

 vine, where it can find fresh food. The work of destruc- 

 tion in a vine, especially if it be vigorous and the soil 

 nutritious, is not completed in a few days. A year may 

 pass without the vine exhibiting any marked sign of sick- 

 ness. The store of vigour which it contains in itself, 

 added to that which it imbibes for some time after it is 

 attacked in the soil, will permit it during one or even two 

 seasons to perform the double functions of nourishing both 

 itself and the parasite which eventually destroys it. M. 



