THE FUNGI 



257 



P- 



FIG. 105. Puccinia graminis. A, section of the cortex of a 

 wheat-stalk, showing a sorus of teleutospores, with the 

 mycelium below. Magnified 150. B, teleutospore germin- 

 ating ; p, p, germ-pores ; sp, sporidia borne on sterigmata 

 arising from the promycelium. Magnified 230. 0, sporidium 

 germinating directly. D, sporidium (sp) germinating 

 indirectly, forming a secondary sporidium (s). Magnified 

 370. E, part of a sorus, showing several nredospores (a) 

 and one teleutospore (t) p, p, germ-pores. Magnified 300. 

 F, uredospore germinating. Magnified 300. (After Von 

 Tavel, Tulasne, and De Baiy.) 



17 



