LEAF-SPOT DISEASES 289 



from performing its natural function. The small brown or light 

 colored spots on the leaves caused by this and Cylindrosporium 

 RuU are familiar to all. 



Treatment. Few experiments with fungicides have yet been 

 made, and these are somewhat conflicting. Treatment with the 

 Bordeaux mixture in Mississippi in 1889 was reported successful, 

 but experiments made by Goff, with Bordeaux mixture and a mix- 

 ture consisting of equal parts of ammoniated copper sulphate and 

 ammonium carbonate, were on the whole unsatisfactory. This was 

 used in the proportion of 12 ounces of the mixture to 22 gallons 

 of water. Professor GofPs conclusions are quoted, here: 



"The foliage of the raspberry is delicate, and cannot endure 

 applications of a corrosive nature. The foliage of the black- 

 berry, though more resistant than that of the raspberry, is more 

 susceptible to injury than that of the apple. None of the treat- 

 ments given are to be recommended for the raspberry, and of 

 the materials used, only the copper carbonate solution can be 

 pronounced beneficial in the case of the blackberry," 



Cylindrosporium Rubi, Ell. and Morgan. Order Melanconiess. 

 Ellis & Everhart, Jour. Myc. 1: 129. Saccardo, Syll. Fung. 10: 500. 



On leaves of cultivated raspberry and blackberry. 



This species is very similar to Septoria RuU in many of its 

 characters; it differs from it chiefly in that the spores of Septoria 

 are borne within a more or less thick-walled and dark-colored 

 conceptacle, while in Cylindrosporium there is no surrounding 

 conceptacle. The two species are often associated, and cannot be 

 distinguished by the naked eye. 



Peronospora Rubi, Eabenh. Order Phycomycetese. Family Pero- 

 nosporaceae. 



Rabenhorst, Fung. Europsei, 2676. Saccardo, Syll. Fung. 7: 263. Halsted, 

 Bot. Gaz. 15: 179, 323. Amer. Garden 1890: 688. 



On leaves of raspberries and blackberries. 



Although a common fungus in Europe, this species was first 

 reported in the United States by Professor Halsted, in 1890, from 

 New Jersey, and later from Long Island. It develops on the 

 under surface of the leaves, and is difficult to detect upon rasp- 



