FUNGI IMPERFECTI 369 



throughout the autumn and winter and careful sections made at 

 different times. In the case of the blotch, as the season advances, 

 the cell aggregates may develop a definite sclerotial-like body 

 (November in Missouri). By March this body has differentiated 

 into a pycnidium (Fig. 188) 25 to 100 fi in diameter, of the 

 Leptothyrium type, bearing hyaline, elliptical spores. The latter 

 measure 12-14 X 2 ~3 A 1 - 



