PESTS OF ORCHARD A>iD FRUIT GARDEN. 



25 



and this disfigurement will proceed until it spreads gradually over the 

 entire tree unless it is checked at once. 



The under surface of the leaves, in the hollows of the blisters, 

 assumes a hoary or frosted appearance, and when examined under the 

 microscope is found to consist of a number of cylindrical cells formed of 

 a transparent membrane closely packed together side by side, each cell 

 or ascus containing the elliptical sporidia (7x5 /jl) in the same manner as 

 in the Pear blister and in the Plum pockets. 



This disease is sometimes called the " curl," from the curling and 

 distortion of the leaves. 



Diseased or fallen leaves should be burned. Branches bearing 

 diseased leaves should be pruned back beyond the point of infection. 

 The disease is rampant if the leaves receive a sudden check from fall of 

 temperature. Activity of the disease has been checked by a sudden 

 increase of temperature. 



Known in France, Germany, Belgium, Sweden, Austria, Italy, 

 North America, South Africa, Algeria, Australia, China, and Japan. 



Garcl. Chron. July 9, 1887 ; Mass. PL Dis. 82, fig. 11 ; Cooke 

 Hdbk. No. 2233 ; Berk. Outl. p. 376, t. i. f. 9, a. 6 ; Sacc. Syll. viii. 3341 ; 

 McAlpinc Fung. Dis. p. 13. 



Peach Freckle. 

 Cladosporium carpophilum (Thiim.). 



This disease is known in the United States as "scab" or "'black 

 spot," and was first observed in Austria in 1877, but has not been recog- 

 nised anywhere else in Europe, although known in the United States and 

 Canada and New South Wales, and is said to spread rapidly when once 

 introduced. 



The fungus is a kind of black mould which attacks ripe Peaches, 

 forming minute round spots or freckles, which are greenish, then brownish 

 or olive. Finally the spots run together and form a brown crust, causing 

 the fruit to crack, shrivel, and decay. It has also been observed on the 

 foliage. The spots are orbicular, and the threads short and slightly 

 branched or simple, with pale ovate conidia, which are rarely septate 

 (20x5 fx). 



So nearly allied to the "Apple scab" that similar treatment is 

 recommended. 



Sacc. Syll. iv. No. 1675 ; Mass. PL Dis. 310 ; McAlpine Fung. Dis. 

 49, pi. vii. 



Peach-spot Mould. 

 Helmmtliosporium rliabdiferum (Berk.), PI. XI. fig. 24. 



This disease first attacked the Barrington Peach in 1864, but has 

 never spread much since that time or proved of any great importance. 



Shallow pits, about half an inch in diameter, appear on the surface 

 of the fruit the centre of which is occupied by a dark mould bearing a 

 profusion of spores, so as to blacken the fingers when touched. The 

 mycelium penetrates deeply into the fruit, which if not gathered in good 



