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the graperies, in the southern counties, for some time after it 
appeared, but gradually spread to the north and west. 
« The first opportunity I had of seeing it was in a grapery 
near Manchester, in 1851, where it occurred that summer. 
<¢ Since that period I have been expecting to hear of it in 
Treland, but am not aware that it made its appearance before 
last year, when it occurred slightly in several places. My at- 
tention was first drawn to it by Mr. Smith, his Excellency’s 
gardener, at the Viceregal Gardens, who stated that something 
was destroying his grapes in one of the graperies, which we 
soon found to be a mild phase of the prevalent disease. This 
year the same house has been again attacked with more viru- 
lence, and also the one next it in the same range. 
«I have, too, observed it on a vine growing in one of the 
plant-houses in the Botanic Gardens; and at Merrion Nur- 
sery the vines in one of the vineries have been so much af- 
fected, as to render their being cut down altogether necessary. 
«‘ Such is a brief sketch of the progress of this malady, and 
{ shall now make a few observations on its ordinary appear- 
ance and results. As in the potato disease, a minute parasi- 
tical fungus is always present, preying on the parts affected ; 
but whether the parasite be the cause of the disease, or conse- 
quent upon it, is still a disputed question, which I am unable 
to throw any further light on. I may, however, state, that 
most observers in this country incline to what is called the fun- 
gal theory, in considering the parasite the cause, especially the 
Rev. Mr. Berkley, whose knowledge of that tribe of plants is 
not surpassed by any other European botanist. | 
«Qn the other hand, some of the ablest observers in France, 
who have studied the subject thoroughly, including Dr. Le- 
veillé, and Monsieur Decaisne, consider the fungus to be de- 
veloped after the tissue of the plant is become diseased, and, 
therefore, the consequence only. 
. “This destructive parasite, which I believe to cause the 
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