Minnesota Plant Diseases. xxi 



FIG. 156. Flax wilt; wilted seedlings. After Bolley 311 



FIG. 157. Spores of the flax wilt fungus, highly magnified. After Bol- 

 ley 312 



FIG. 158. Flax wilt; the fungus threads around the root of an attacked 



flax plant. Highly magnified. After Bolley 312 



FIG. 159. Flax wilt; a section of a flax root, with fungus threads and 



spores at the surface. Magnified. After Bolley 313 



FIG. 160. Orange rust of raspberry and blackberry. Original 316 



FIG. 161. Winter spores of the asparagus rust. Highly magnified. 



Microphotograph by E. W. D. Holway 318 



FIG. 162. Rust of bean. After Clinton 319 



FIG. 163. Pore-fungus root-rot of currant. Original 321 



FIG. 164. Potato scab. After Clinton 326 



FIG. 165. Anthracnose of bean. After Halsted 328 



FIG. 1 66. Potato blight. Early stages of the blight on the leaves. 



After Clinton 332 



FIG. 167-. Potato blight. Later stages on the leaves. After Clinton... 333 

 FIG. 168. Downy mildew of muskmelon. Blighted vine in the field. 



After Clinton 335 



FIG. 169. Downy mildew of muskmelon, showing the under surface of 



an attacked leaf. After Clinton 336" 



FIG. 170. Downy mildew of muskmelon. Under surface of an attacked 



leaf. After F. C. Stewart 337 



FIG. 171. Downy mildew of melons and cucumbers. Spores and spore- 

 bearing threads. Highly magnified. After Humphrey 



and F. C. Stewart 338 



FIG. 172. Bacterial rot of potato. After Clinton 34O 



FIG. 173. Bacterial rot of squash. After Clinton 34 1 



FIG. 174. Black rot of cabbage. A badly infested field. After H. L. 



Russell 342 



FIG. 175. Black rot of cabbage. Artificial infection of cabbage plants. 



After H. L. Russell 343 



