280 



Mycologia 



fected panicles and some of the infected, lower leaves of the 

 younger stools were dead. 



Fig. i. Urocystis agropyri (Pruss.) Schroet. on redtop. A. Smutted red- 

 top plant (X 0.5), showing (1) shredding of leaf between the veins where the 

 spore balls are deposited; (2) twisting of rachis. B. Photomicrograph of 

 spore balls from the redtop plant shown in A ( X 4°°) ; (3) spore ball contain- 

 ing one fertile spore; (4) two fertile spores; (5) four fertile spores. 



The spore balls are oblong-spheric to spheric, from 21 to 33^ 

 in length, occasionally 40/A. The sterile cells vary from a very 



