Memoir SO 



Plate V 



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FREE-HAND SECTIONS OF SCLEROTIA OF R. TULIPARUM 



A, Young stage of sclerotium from pure culture, showing the external mycelium and 

 the deep coloration of cell walls in the region where the pseudorind is forming. 



B, Mature sclerotium from pure culture, showing elongated outer cells and deeper- 

 colored walls of the pseudorind; the external mycelial weft is largely torn away. 



C, Mature sclerotium from bulbs in soil; the cells of the pseudorind have collapsed. 

 All X 145 



