DISEASES OF THE VINE. ] 585 



when they are approaching maturity, and then the diseased 

 b.rries take on an ashy grey colour, shrivel and dry, 

 their surface becoming covered with the ashy grey fruc- 

 tifications of the fungus. The attack may develop when 

 the bunches are still in flower, and then they rot and 

 drop off. The attack on the green parts and flowers in 

 vines grown in the open air was formerly considered 

 rare, but lately has been prevalent in certain districts of 

 France and Northern Africa. The iungus attacks also 

 the newly grafted plants or cuttings during the forcing 

 process, and is the cause of many failures, and it thrives 

 also on any recent wounds of the green parts of the vine. 

 On the other hand, an abortive or larvate form of the 

 disease attacks the ripening berries in the Rhenish 

 provinces, and provokes certain alterations owing to 

 which the juices of the grape become concentrated, with 

 an increase in glucose and in glycerine, and the wine 

 which is produced takes a more delicate flavour, hence 

 this form of disease is called the noble rot of the grape. 

 However in other regions of Prance as well as in Italy 

 and elsewhere the attacks of Botrytis are justly dreaded 

 as they invariably result in wines of poor quality. 



As a remedy against this disease it has been sug- 

 gested to apply to the bunches, at the time when the 

 berries are beginning to ripen, one or two dustings at an 

 interval of a few days, with powdered lime or powdered 

 chalk, preferably with the addition of a small quantity, 

 about 5 per cent , of finely powdered alum. 



Vine-mildew. Is due to Uncnmla spiralis Berk. = 

 U. americana Howe U. nee a for Ferra is Oidium Tkt- 

 ckeri Rerk.rzs?ft/ie Juckiri Tul. The fungus is 

 generally known in its conidial form (Oidium), the 

 ascophorous form (Uncinuh ) being very rarely met vuth. 

 It appeared for the first time in Kurope on the vines 

 cultivated under glass in Margate (England) in 1845. 

 In 1847 it was noted in France and Belgium, and soon 



