270 DISEASES OF FIELD & GARDEN CROPS. [OH. 



Fia. 125. LETTUCE MILDEW. 



Peronospora ganglionifoi-mis, Berk. Enlarged 400 diameters. 

 Tip of branchlet with spicules and conidium, 1000 diameters. 



the saucer's edge. Each spicule is like one of the 



