CH. X] IMPERFECT FUNGI 477 



science, abundant and alluring problems still await the 

 coming investigator. 



Ecologically the Ascomycetes and Basidiomycetes are all 

 hysterophytes, parasitic or saprophytic upon land plants 

 almost entirely. Phylogenetically, their relationships have 

 already been indicated (pages 448 and 464), and are shown, 

 as they seem most probable, in Figure 275. 



