306 NOTICES OF THE MEETINGS [April 29, 
it enlarges and radiates irregularly in fine filaments, which often 
cover the whole surface, extending with great rapidity. These fix 
themselves by imperceptible attachments, which do not appear to 
penetrate the cuticle; numerous branches from the mycelium are 
unfruitful; others are jointed and rise vertically like the pile of 
velvet; the upper joint enlarges, rounds itself into an elliptical 
form, ripens, separates, and is carried off with the slightest motion 
of the air, to find another grape upon which it can be developed. 
Warmth and moisture favour its rapid fructification; a succession 
of spores rise from the same branch ; and often two, three, or four, 
ripen and disperse almost at the same time. Its effect upon the 
grape is to exhaust 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 disease has returned with increased virulence in each 
succeeding year. In 1847, 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 neighbourhood, and con- 
tinued to extend from place to place; but until 1850 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 de- 
testable. 
In 1852, the Oidium Tuckeri reappeared in France with increased 
and fatal energy; it crossed the Mediterranean to Algeria, shewed 
itself in Syria and Asia Minor, attacked the Muscat grapes at 
Malaga, injured the vines in the Balearic Islands, utterly destroyed 
the vintage in Madeira, greatly injured it in the Greek Islands, and 
destroyed the currants in Zante and Cephalonia, rendering them 
almost 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 millions 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. ‘Traces of its influence have been seen in the Loiret, 
Loire-et-Cher, and Maine-et-Loire. The vineyards of the Medoc 
in 1851 were untouched, and the cultivators laughed at the existence 
of the Oidium; but last year the disease shewed itself everywhere 
in the Gironde, even to the borders of the celebrated Medoc, and 
between the vineyards of the Medoc and the river at Pauillac and 
at Macau, with serious injury. Inthe Lower Pyrenees the wines of 
Jurancon were affected. The Haute Garonne was generally attacked ; 
and at Toulouse one proprietor. who usually sent to Paris 10,000 
