BOTAXY. 341 



the juices of the cuticle, which ceases to expand with the pulp of the 

 fruit ; it then bursts, dries up, and is utterly destroyed. This fatal dis- 

 ease has returned with increased virulence in each succeeding year. In 

 1817 the spores of this Oidium reached France, and was found in the 

 forcing. houses of Versailles and other places near Paris ; but the disease 

 soon reached the trellised vines, and destroyed the grapes out of doors in 

 the neighborhood, and continued to extend from place to place ; but un- 

 til 18-50 it was chiefly observed in vineries, which lost from this cause, 

 season after season, the whole of their crops. Unhappily, in 1851, it was 

 found to have extended to the south and south-east of France and Italy, 

 and the grapes were so affected that they either decayed, or the wine made 

 from them was detestable. In 1852, the Oidium Tucker i reappeared in 

 France with increased and fatal energy ; it crossed the Mediterranean to 

 Algeria, has shown itself in Syria and Asia Minor, attacked the Muscat 

 grapes at Malaga, injured the vines in the Balearic Islands, utterly de- 

 stroyed the vintage in Madeira, greatly injured it in the Greek Islands, 

 and destroyed the currants in Zante and Cephalonia, rendering them al- 

 most unfit for use, and so diminished the supply that 500 gatherers did 

 the ordinary work of 8000 ! But it is in France that its frightful ravages 

 are chiefly to be regarded as a national calamity, where the produce of the 

 soil in wine is said to exceed 500,000,000 of hectolitres ; two-fifths of the 

 usual quantity of wine made there has been destroyed, and what has been 

 made is bad. It has not touched with equal severity all the departments. 

 The vineyards of the Medoc in 1851 were untouched, and the cultiva- 

 tors laughed at the existence of the Oidium ; but last year the disease 

 showed itself every where in the Gironde. The Eastern Pyrenees, 1'Aude, 

 1'Herault, and a great part of Gard, were all deplorably affected, and at 

 Frontignan and Lunel the vineyards were abandoned in despair. Thou- 

 ands of laborers were thrown out of employ, and the distress was awful. 

 Wine in France is the common drink of the peasant ; upon this, his 

 bread, and some legumes, he labors ; but the wine, bad as it is, has risen 

 to double, and in the countries most injured even treble, its ordinary 

 price. M. Mohl has most carefully examined whether the Oidium of the 

 grape lives on other plants besides the vine, but he is decidedly of opinion 

 that it does not. Some persons have supposed that it was caused by in- 

 sects, because occasionally they have been found on diseased vines ; but 

 the idea is now utterly rejected, for not the slightest appearance of disease 

 precedes the fungus, which creeps over the epidermis, but does not enter 

 its tissues. It envelops the grape, absorbs the juices of the superficial 

 ^olls, and stops the growth of the cuticle. The pulp expands within the 

 fruit, bursts longitudinally, its juices are lost, and it dries up. In an 

 early stage of the disease the fungus may be wiped off, and the fruit will 

 come to maturity. The Oidium never matures on decayed vegetable sub- 

 stances ; it lives and fructifies only on living tissues. The poor peasant 

 of the Bouches du Rhone believes that the cause is bad air ; but at Genoa, 

 Grenoble, Lyons, Dijon, and Strasbourg, the people attribute it to gas- 



