114 



THE FUNGI WHICH CAUSE PLANT DISEASE 



forms in which the asci are without either stroma or covering, 

 (Protodiscales, p. 125); others in which the asci are not even in 

 groups but are scattered irregularly throughout the ascocarp 

 (Aspergillales, p. 164); and still others with the asci neither in 

 regular groups nor covered (Protoascomycetes, p. 119). One 

 further deviation from the typical form occurs in the Hcmiascomy- 



Fiu. 7-1. — The large ascocarp of the morel. After Freeman. 



cetes which possess a sporangium-like structure resembling that 

 of the typical Zygomycete; but a mycelium like that of the typical 

 Ascomycetes. This is by many regarded as the transition form 

 bridging the gap between and indicating the kinship of these two 

 groups; a view strongly supported by the existence of very similar 

 sexual processes in the two groups. 



Besides the ascus the Ascomycetes possess many other kinds of 



