GENERAL FEATURES OF THE GROUP 



1. Phylogeny 



As the higher land plants are thought to have originated 

 from lower aquatic forms, so the Discomycetes or cup-fungi, as 

 well as the other higher fungi, which might be referred to as the 

 "terrestrial thallophytes," are also believed to have been de- 

 rived from aquatics. We would naturally look for the ancestors 

 of these chlorophylless plants among the chlorophxll-bearing 

 forms, the algae. 



While most mxcologists will concede that the fungi have 

 evolved from the algae, directh' or indirecth', there seems to 

 be a difference of opinion as to whether their course has been a 

 direct or an indirect one. On this point there are two theories, 

 one that the ascom\cetes have come directly from the red algae 

 and the other that the\' have come indirecth' through the 

 Phycomycetes or lower fungi. 



Those who hold the former view base their argument on the 

 similarity which they seem to see between the sex organs and 

 other structures of the two groups, especially the resemblance 

 of the trichogyne of the ascomycetes and of the red algae. 

 Those who oppose this view contend that they can see no analogy 

 or homology between the unicellular trichogyne of the red algae 

 and the multicellular trichogyne of the ascomycetes. Even in 

 Pyronema where the trichogyne is itself unicellular the wall at 

 the base of the trichogyne is a little barrier which has caused a 

 great deal of discussion. 



These and other views advanced are, however, only hypo- 

 thetical and since the purpose of the present work is to treat 

 the Discomycetes as they are rather than to philosophize on 

 hoiv they might have come to he, we will proceed with the task in 

 hand and leave the question of their origin for those who have 

 given more thought to this phase of the work. For a full dis- 

 cussion of the subject see Atkinson on the "Phylogeny of 

 the Ascomycetes" (Ann. Missouri Bot. Gard. 2: 315-376). 



2. Gross Morphology 



Like all of the higher fungi, the Discomycetes or cup-fungi 

 present two distinct phases in their life histories, the growing 



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