. The Canadian horticulturist [monthly], 1893. Gardening; Canadian periodicals. GOOSEBERRY MILDEW. Sir, -Could you in the Canadian Horticulturist say exactly what the mildew is, if it effects onlj the leaves, or the leaves and fruit of the gooseberry, and if there is any remedy for it '.' A Subscriber, Montreal, Que. SHIS mildew, according to Scribner, belongs to the same general class of fungi as the powdery mildew of the grape. It has the specific name of Sphaerotheca mors-uvae. It attacks its host only on the surface, giving the exterior a whitish, powdery appearance. The slendt;r filaments

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. The Canadian horticulturist [monthly], 1893. Gardening; Canadian periodicals. GOOSEBERRY MILDEW. Sir, -Could you in the Canadian Horticulturist say exactly what the mildew is, if it effects onlj the leaves, or the leaves and fruit of the gooseberry, and if there is any remedy for it '.' A Subscriber, Montreal, Que. SHIS mildew, according to Scribner, belongs to the same general class of fungi as the powdery mildew of the grape. It has the specific name of Sphaerotheca mors-uvae. It attacks its host only on the surface, giving the exterior a whitish, powdery appearance. The slendt;r filaments of the fungus throw out growths which draw nourishment from its host, and finally send out upright growths which form oblong cells by means of a division wall across the top. See Fig. 535. These cells are summer spores, and each one is capable of immediate germination. They are pro- duced as described, in large numbers, and this accounts for the rapid spread of the fungus in the summer time, the spores being very easily carried about in every direction by the wind, even to very distant places. In Fig. 535 the upright branches are shown as at a, and the summer spores in process of forma- tion by division at b, one or two having fallen off. Each of these will quickly germinate if they" lie in a moist place during the heat of the summer, the first movement being to throw out horizontal threads, to be succeeded by the upright ones, thus repeat- ing the life history as as above described. This mildew first attacks the young half-grown leaves and ends of the young shoots, and very soon after, patches of the same may be found upon the fruit itself. In order to enable this evil fungus to survive, there is another class of spores called winter spores. In the case of the powdery mildew of the grape, these are not mature until late in the season, but in the gooseberry mildew they are found in maturity as early as the month of June. Fig. 536, a and b represents two filaments uniting,