^'cO 
I. ■ 
THE ASCOMYCETES OF OHIO.—I 
Preliminary Consideration of Classification* 
BRUCE fink 
All classifications of ascomycetes hitherto followed have been highly 
artificial, nor are the data for a satisfactory disposition at hand. 
Hitherto, these fungi, except for lists from two states and certain works 
mentioned in this paper, have been placed in two groups. In the work to 
follow, all the ascomycetes of Ohio will be treated as a single class of 
fungi, and some defense of this method is in order. 
The reasons for treating ascomycetous lichens and other ascomycetes 
together involve mainly the following three considerations: first, the 
nature of the lichen in general; second, a review of the similarity of 
lichens and other ascomycetes; third, a discussion of the origin of all 
ascomycetes, with a view to showing relationships within the group. 
These three matters will be treated in order and as briefly as is consistent 
with clearness. Frequent reference will be made to other papers where 
more lengthy discussions of certain phases of the problem may be found. 
Until the time of Schwendener (57), it was generally believed that 
the chlorophyllous cells found in lichens were the chloioplasts of these 
plants. Bornet (12) grew lichens from spores in cultures and saw them 
attack algae. Bonnier (11), by similar methods, obtained mature fruited 
plants of Xanthoria parietina and Rinodina sophodes. Moller (47) fol¬ 
lowed by growing Calicium parietinum in cultures without algae and 
obtained plants that produced spermagonia and probably archicarps as 
well. Fink (31) has reported on the frequent growing of various algal 
hosts in the same habitats with lichens. 
Had it not been for clinging to erroneous tradition, the researches 
referred to above and others like them would have convinced all botanists 
that the lichen is a fungus living in some peculiar relation with an alga. 
Unfortunately, Reinke (53), Schneider (55), and others have aided in 
retarding progress, and a considerable number of botanists still cling to 
some modification of the early view. Peirce (52), Elenkin (25), and 
Danilov (20), with their researches which greatly strengthen belief in the 
parasitism or the saprophytism of lichens on algae, have succeeded in 
turning the attention of botanists toward more plausible conclusions. 
We need only to advance definitely to the widely but rather hazily 
understood idea that the lichen is a fungus, the alga being its host and 
* Contributions from the Botanical Laboratory of Miami University—XI. 
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