Dec. 1896.] 



INJURIOUS INSECTS AND FUNGI. 



293 



that of the ordinary conidia, or spores, shown at D (Fig. 2), 

 and that of the spores — zoospores — from the perithecia 

 (C, Fig. 2). Both of these spores are conveyed by the wind, 

 by birds, and insects. The winged form of aphides, and " lady 

 birds " (Coccinellce), which fly from hop plant to hop plant, and 

 run over every leaf and cone, and inside the cones, in search of 

 aphides, are notable spreaders of this infection. 



In the summer the progress of the mildew was arrested 

 by treatment with powdered sulphur, which the abundance of 

 sun-heat made very efficacious. When the weather changed, 

 and became gloomy and wet, sulphuring was abandoned in 

 many cases, and where it was continued it failed in efficacy on 

 account of the rain and low temperature, and the heavy rain 

 had washed it off from the cones sulphured late in the summer. 



O 93997. 



D 



