ADDENDA 



The following were unfortunately omitted from their 

 proper place in the book : — 



ROSE MILDEW 



(Sphaerotheca pannosa, L6v.) 



Too frequently the foliage, young shoots, and flower- 

 buds of cultivated roses become more or less covered with 

 a delicate white mildew, which soon presents a mealy 

 appearance, due to the formation of myriads of conidia. 

 The conidia are scattered by wind, insects, birds, or syring- 

 ing ; and generally the disease spreads at an alarming rate, 

 unless prevented, after having once appeared. As a rule 

 the leaves curl and fall early in the season, while formation 

 of conidia is still progressing. On the young shoots and 

 fruit, the more permanent parts, after the crop of conidia 

 is completed, the mycelium increases in quantity, finally 

 presenting a dense, velvety appearance, and often with a 

 dingy yellow tinge. Later in the season winter fruit, under 

 the form of minute black points, may be found imbedded 

 in the dense mycelium. The spores of the winter form 

 of fruit germinate the following spring, and produce the 

 conidial phase of the disease. 



Preventive Means. — Flowers of sulphur mixed with 

 about one-third of its volume of slaked lime dusted on the 



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