VINE-MILDEW. 265 



not exhibited the least interruption. The same may be said of 

 its vegetation in summer and autumn, inasmuch as the only 

 visible deviation from the normal condition consisted in the 

 circumstance that the leaves were rather less smooth and even 

 than healthy Vine leaves are wont to be and approached the 

 condition of what Botanists call "folium buUosum." In every 

 other respect the growth of the stem and leaves was completely 

 normal, and when the leaves fell in autumn, there was nothiug 

 unusual in the appearance of the Vines ; the condition of the fruit 

 was in consequence so much the more surprising. Above all it 

 was at once apparent that its growth was very much impaired, 

 In the middle of August the greater part of the berries at Bozen 

 had acquired only the size of peas, and many were still smaller ; 

 a few only had attained their normal dimensions, and this mostly 

 in the case of single berries, and only with extreme rarity 

 throughout a whole bunch.* The cuticle of the berries, which 

 had been arrested in their development, was thickly studded with 

 little brown warts, ai'ising from the points of attachment of the 

 threads of the fungus previously described ; in other respects they 

 were perfectly green. In a few more malignant cases the brown 

 specks had coalesced into larger spots, which extended over a 

 greater or less part of the berry, consisting of the dead outer 

 layers of cells and presenting a tough membrane. 



The more the cuticle was degenerated, and the further the 

 degeneration extended over the berries, so much the more was their 

 growth impeded. If it was defaced only in a single confined 

 spot, the unaffected part swelled while the growth of the diseased 

 portion was impeded, and consequently the berries assumed an 

 irregular form. In general the whole cuticle was diseased and 

 presented such a resistance to the growth of the parenchym, that 

 it was checked in its development. The firmness of the cuticle 

 was, however, frequently insufficient to withstand the pressure of the 

 parenchym as it strove to become expanded ; in these cases a 

 fissure in the cuticle was formed, small at first, but widening with 

 the expansion of the flesh into a deep gaping crack. This 

 appearance was the more common when strong rain fell after 

 preceding diy weather, as was the case at the commencement of 

 September, when not only the unripe berries, but those which 



* A notion of the extent of the evil may be conceived from the fact 

 that in Meran, where the Vine-mildew was less destructive than at Bozen, 

 it was only with difficulty that the few hundredweights of grapes, which 

 were wanted by the invalids, could be collected. 



T 2 



