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TEXT-BOOK OF FUNGI 



by Brefeld as being the progenitors of the group he terms 

 Hemibasidiomycetes, where the basidium is transversely 

 septate. In the second type, represented by Tilletia^ the 



FlG. 90. Ustilago hordei, a species parasitic on barley. 

 The mass of spores does not become loose and powdery 

 at maturity as in most species of Ustilago. Nat. size. 



promycelium is short and not divided by septa, but bears 

 a variable number of secondary spores at its apex. The 



