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and serious, and amounting in fact to one of the established and 

 recognized diseases of the vine ; but in this country nothing of the 

 sort has hitherto been reported. On the 15th May, in a vineyard 

 near Normal, belonging to the Phoenix nursery, I observed two grape 

 vines of the variety known as "Taylor's Bullet," the leaves of which 

 were curiously curled and crumpled, on some of the vines scarcely 

 a leaf remaining unaffected. A careful examination of the injured 

 surfaces under a microscope, demonstrated the existence on the 

 under surface of the leaves, of considerable numbers of a minute 

 Phytoptus having the general appearance of that described from 

 European vineyards ; and a further search in this vineyard showed 

 a large number of other vines more or less seriously affected, some 

 rows of young Clintons being in fact so extensively diseased that 

 hardly a leaf could be found which did not give evidence of the 

 presence of the mite. 



Upon Concords immediately adjoining, and other thick-leaved and 

 woolly varieties, there seemed to be neither trace of the injury nor 

 of the Phytoptus. It is possible, however, that the mites were 

 actually present on these leaves, but that these varieties were not 

 susceptible to injury by them. Owing to the thick felt of hairs 

 upon the leaf surface, it would have been extremely difficult to 

 demonstrate the mites even if they had been present in considerable 

 numbers. 



The injury presents the form of peculiar warty elevations upon 

 the upper surface of the leaf, and corresponding depressions on the 

 under surface, these varying in size from one -twentieth to one-tenth 

 of an inch in diameter, although adjacent elevations are frequently 

 fused into irregular patches of much greater size. The larger 

 veins of the leaf did not share in this deformity, and the effect 

 was a distortion such as might result from a shortening of these 

 veins and the consequent folding and crumpling of the leaf. 

 The diseased leaves were much smaller than natural, and were fre- 

 quently more or less folded together lengthwise, and the edges were 

 also sometimes considerably incurved. On the older foliage, where 

 the injury was of longer standing, the elevations on the upper sur- 

 face were more or less browned or reddened, but when fresh they 

 were still the natural green of the plant. Many elevated spots upon 

 these leaves were pale, sometimes almost transparent, owing to the 

 defective formation of the chlorophyll — a complete demonstration of 

 the interference with the function of the leaf and the consequent 

 effect upon the vigor of the plant, produced by these parasites. 



The European writers describe and figure a peculiar development 

 of abnormal hairs (technically called an erineuin) upon the concave 

 surfaces of the diseased patches on the leaves, but in the Clintons 

 and Taylors nothing of this sort occurred, the inner surfaces of the 

 cecidii (as these morbid elevations are called) being entirely smooth 

 and destitute of pubescence of every kind. It is possible that the 

 absence of an erineum was due to the early period at which the 

 injury was observed, but I think it more likely that it is to be ac- 

 counted for either as due to the difference in species of the Ameri- 

 can and the European grapes and the consequent difference in the 

 reaction of the leaf from the injuries inflicted, or else that the 

 species of Phytoptus occurring here is not actually identical with 



