DISEASES OF PLANTS. 247 



dwarfed by court-non^. The vines showed improvement the first year, and 

 more decidedly the second year. After the third year's treatment the recovery 

 is considered to be complete, the new growths being apparently normal as to 

 development and product. 



Development of downy mildew as related to conditions of the medium, 

 O. Mengel {Compt. Rend. Acad. Sci. [Pom], 157 (191S), No. 4, pp. 292-294).— 

 Observations made at the station for agricultural meteorology at Perpignan 

 are said to show that in this region, where the winds predominant in periods of 

 mildew outbreak are from the sea, the localities of greatest infection are the 

 elevations most exposed to sea winds presumably bearing comparatively few 

 spores; this is apparently because of the greater humidity and warmth, favor- 

 ing germination. In the observation period in question it is held that the two 

 days of northwest showers conferred receptivity upon the grape stocks and 

 that three days of warm moist winds from the northeast and southeast 

 developed the infection. 



Summarizing the conclusions arrived at from recent studies, the author con- 

 cludes that the presence of mildew and degree of its attack depend upon gen- 

 eral causes, such as variations of atmospheric conditions, which may be wide- 

 spread ; upon secondary causes, including such factors as the nature and vi- 

 tality of the stock, the composition of the soil, and exposure of the situation ; 

 and upon accidental causes, such as fertilizers, dressings, and the presence of 

 overflow water. 



The white rot of grapes and its treatment, L. Degrully (Prog. Agr. et Vit. 

 {Ed. VEst-Gentre), 34 {WIS), No. 36, pp. 289-291, pi. i).— According to the 

 author, the white rot due to Coniothyrium diplodiella is particularly destructive 

 to the fruit of certain varieties of grapes. The fungus is considered to be 

 semiparasitic, usually attacking the fruit and vine through wounds. 



Spraying for black rot or mildew will at the same time protect against the 

 occurrence of the white rot. The fungicides for this purpose should contain a 

 large amount of copper. 



This fungus, unlike the Botrytis which causes the gray rot, is said not to 

 produce any oxidizing enzyms, and as a result does not affect wine. 



Diseases of Azalea indica, H. Behnsen {Gartenwelt, 17 {1913), No. 36, pp. 

 499, 500). — A brief discussion is given of the injury to A. indica by Fuligo 

 septica, requiring the removal of the slime mass and application of potassium 

 nitrate ; by Septoria azalew, Bordeaux mixture of 1 per cent strength being 

 recommended as a preventive measure; by an Exobasidium of undetermined 

 species, no remedy being prescribed; and by leaf fall ascribed to means used 

 for securing rapid growth. Several injurious animals are briefly discussed. 



Carnation stem rot, H. W. Anderson (In Floriculture Research at the Ex- 

 periment Station. Urbana: Univ. III., 1912, pp. 15-22). — This is a paper pre- 

 sented before the annual meeting of the Illinois State Florists' Association and 

 consists of an account of observations and experiments on the carnation stem 

 rot due to Rhizoctonia. An outline is given of experiments in progress relating 

 to this disease, and a number of other fungus troubles are briefly mentioned. 



Infection experiments with Phoradendron villosum, K. voN Tubeuf {Na- 

 turw. Ztschr. Forst u. Landw., 11 {1913), No. 3, pp. 171, 172; a'bs. in Bot. 

 Centbl., 123 {1913), No. 12, p. 29// ) .—Attempts to grow P. villosum on several 

 European trees named gave no further results in any case than germination 

 of the mistletoe seed. See also a previous note (E. S. R., 29, p. 243). 



Notes on black canker of chestnut, E. Barsali {Riv. Patol. Vcg., 6 {1913), 

 No. 4-5, pp. 107-110).— Referriug to recent reports by Petri (E. S. R., 29, p. 156) 

 and others on black canker of chestnut, the author contributes some observations 



