_Characteristics._--The first, or at least the most characteristic signs of this disease appear especially after a summer rain, or after the first fall rain. The leaves then become spotted with yellow. The following season these yellow spots appear as if fused together, and many leaves become entirely yellow, except the veins, which stand out bright green. Some leaves are invaded by the yellow from the edges, while the veins as before remain green. These yellow spots soon turn brown, the leaves dry up and curl slightly backwards and finally fall off, leaving the canes bare. During the very first appearance of the vine plague, many leaves turn brown and dry up in certain spots in the vineyard without the previous appearance of any yellow spots. The drying of the leaves proceeds either from the center of the spots, or from the margin of the leaves, destroying both the leaves and their veins. Later on in the fall a new crop of leaves appear, but these leaves are small or very small, bright green and sickly, and do not continue to develop after they have reached a certain size, different in different vines. In red varieties of grapes, the yellow spots in the leaves gradually turn red or claret colored, often resembling the most beautiful autumn leaves. In districts where the disease is common, these leaves are generally known as calico leaves on account of their peculiar markings. The canes do not attain their regular growth, and fail to mature in the fall, or mature only in spots, the balance of the wood remaining dull green. The inner parts of the canes are, as a rule, more mature than the tips. Very often only one or two joints nearest the stem mature, and in bad cases no part of the canes mature, but at the advent of the rain turn black and die. Late in the fall the tips of the green canes turn black, dry up and snap off like glass when touched. The pith turns in the older canes dark brown, dries up prematurely and dies, while in very young canes the pith remains watery like a semi-transparent jelly. Many vines have no mature wood when the leaves have fallen in the autumn, while others again have some. While the spotted leaves may appear all over the vineyard, the diseased canes appear on vines in spots, these spots in the vineyard growing larger year after year. A dead vine may be seen in the midst of healthy ones, while a healthy vine, on the other hand, may remain in the midst of dead ones. It takes generally several years to kill the vines, and some varieties are hardier than others. Some Muscats may succumb in one year, while some will last for three years or more. The roots remain alive and healthy longer than any other part, and, when the top of the vine has already died, it is common to see the root send up a healthy sucker, which, however, in its turn, will become diseased and die. It is likely that the vines in some districts will suffer more than in others, and in places the vines may not become seriously injured by the disease.