DISEASES OF PLANTS. 173 



cessfully combated the gray rot of grapes due to Botrytis cinerea by heavy applications 

 of powdered hydraulic lime to the vines. 



Treatment for control of gray rot of grapes, E. Zachaeewicz ( Prog. Agr. et 

 Yit. | Ed. UJEst), 25 (1904), No. ..'.', pp. 651-655, pi. 7).— The author claims that by 

 treating vines with a solution of copp,er sulphate, powdered soap, and water, followed 

 with applications of sulphur and sulphosteatite or plaster, powdered soap, and sul- 

 phosteatite it is possible to prevent injury to grapes by Botrytis cinerea. 



In an editorial note a doubt is expressed regarding the efficiency of the present 

 fungicides and mixtures for the control of this disease. 



The brunissure of the grape, L. Ravaz (Prog. Agr. et Yit. ( Ed. L'JEst i, 25 ( 1904), 

 No. 3, pp. 69-72, figs. 6). — The author briefly describes the brunissure of the grape, 

 which he holds is not of fungus or bacterial origin, but is due to a weakened condition 

 of the plant resulting from overbearing. 



Notes on verdigris in combating grape mildew, E. Ohuaed and CDusserre 

 (Chron. Agr. Canton Vaud, 17 (1904), No. 9, pp. 291-297). — Studies are given of the 

 relative value of 2 forms of verdigris which are in common use as fungicides for use 

 in preventing grape mildew. One, which is called neutral or refined verdigris, con- 

 tains from 31 to 32 per cent copper and is distinguished by its ready solubility in 

 water, while the second form, known as basic or adherent verdigris, is less soluble 

 in water and remains in suspension for a considerable time. It is less rich in copper, 

 containing only 23 or 24 per cent on an average. 



The experiments conducted with these fungicides showed that the soluble verdi- 

 gris was more easy of application, did not present any visible traces after some little 

 time, nor was it washed off by rains if the treatment was given the vines at a time 

 when they were completely dry. A 0.5 per cent solution gave results as satisfactory 

 as when a more concentrated form was employed. 



The results of an investigation with grape mildew and its treatment in 

 1903, E. Chuard and H. Faes (Chron. Agr. Canton Vaud, 17(1904), No. 8, Sup., pp. 

 51). — The results of an investigation into the mildew of grapes, times of its invasion in 

 different regions, methods of treatment and their results, and conclusions regarding 

 this disease are given. 



Much of the information published is based on returns received from circular letters 

 sent out to correspondents throughout every grape region of Switzerland. Formulas 

 for the preparation of fungicides and directions for application are given, and it is 

 concluded that the proper use of fungicides, even in years when mildew is very 

 prevalent, reduces the amount of injury to a great extent. 



The wintering of the powdery mildew of the grape, G. de Istvanffi ( Bui. 

 Agr. AlgSrie et Tunisie, 10 (1904), No. 6, pp. 130-132). — The importance of determin- 

 ing the method by which the powdery mildew is carried over from one season to 

 another has led to numerous investigations. 



In Europe this fungus seldom produces the perithecial form and consequently 

 must have some other method of propagation. The author reports having observed 

 in October the mycelium of the fungus as well as its cpnidial stage on buds which 

 were produced on late shoots. The microscopical examination of the tissues of these 

 buds showed that the fungus had penetrated them and fructified. Cuttings of vines 

 attacked by the mildew in autumn were collected through the winter which showed 

 a presence of the mycelium in considerable quantity. A third method of spending 

 the winter is said to he on the dried clusters of grapes remaining on the vines. An 

 examination made in January and February showed the mycelium quite abundant. 



Based upon the author's investigations, he recommends for the destruction of this 

 fungus winter treatment of vines and the collection of all dried clusters, etc. 



Occurrence and treatment of grape powdery mildew, L. Ravaz (Prog. Agr. 

 et Yit. ( Ed. I? EM), 2.5 (1904), No. 22, pp. 645-651).— The author reviews the recent 

 publications of Istvanffi (see above) regarding the method by which the grape pow- 



