218 



MANUAL OF POISONOUS PLANTS 



Fig. 57. Smut spores of various kinds. 1. Tall meadow 

 oat smut (Ustilago pcrcnmins). 2. Timothy smut {U. striae- 

 fornris). 3. Rye smut (Urocystis occulta). 4. Cheat smut 

 (Ustilago bromiiora). 5. Foxtail smut (U. neglcctu). 6. Nlil- 

 let smut (U. fanici miluicei). 7. Sandbur smut (U. Cesatii). 

 8, 9. Tilletia germinating. 10. Secondary spores from conid- 

 ia. 11, 12. Urocystis spores germinating. 13, 14. Mycelium 

 of same. h. Suckers or haustoria. h. Hyphae passing from 

 one leaf to another. 8-14 after Wolff. 



