DISEASES OF THE VINE. ] 587 



ticular type rests chiefly if not entirely in the fineness of 

 the particles of sulphur and in its purity from admixtures 

 of earthy substances. The use of sulphur containing 3 

 to 5 % of sulphate of copper has the advantage that it is 

 also a preventive against vine-blight. Spraying the vines 

 with a solution of common salt (i kilog to about 100 

 litres of water) or with a mixture of about i part of sea- 

 water to two parts of fresh water, has given fairly good 

 results, both against vine-blight and vine-mildew, -and 

 may be used as a substitute, should -sulphur be at any 

 time unobtainable. 



Black-rot is due to Guignardia Bidwelli Viala et 

 Ravaz. = r. ampelicola Roze.=P/ioma uvicola Berk et 

 Curt. = Physalospora Bidwellii Ellis. Phylhsticta viti- 

 cola B et C. This is another disease of American origin, 

 which was first noted in Europe in 1885, and has caused 

 notable injury to the vineyards in certain districts of 

 France. The fungus attacks the leaves, the shoots and 

 the bunches. The leaves are infected in May or early in 

 June, with the production of elongated spots of a red or 

 reddish colour with a dark brown margin, and on these 

 spots numerous black clots are formed which are the 

 fructifications of the fungus. The same spots are formed 

 on the green shoots, the lesion extending deep into the 

 woody tissues. On the green berries the attack develops 

 like sunburn, but the brown spot extends, and the berry 

 shrivels and partly dies, assuming a purplish or black 

 colour, and on the rind of the diseased berry the fructi- 

 fications of the fungus are soon formed as small promi- 

 nent black dots The diseased berries which afterwards 

 drop to the ground produce in spring the two types of 

 fructifications of the fungus, viz : the conidial and the 

 ascophorous, by means of which the disease is reproduced 

 on the new tissues. The development of the fungus is 

 favoured by a moist condition of the atmosphere in May 

 and June. The remedy most in use against this disease, 



