Fink; Classification of Lichens 
99 
Many botanists were asked, two years ago, to express them- 
selves regarding the classification of lichens, and the results of 
the correspondence have appeared in Mycologia (55) for Sep- 
tember, 1911. It was supposed that those who replied would 
deem it necessary, in sustaining their views regarding classifica- 
tion, to state clearly their ideas concerning the more fundamental 
problem of the nature of lichens. Of the 42 replies quoted, 10 
contain no words from which any inference can be drawn con- 
cerning the nature of these plants. The other 32 replies touch 
the matter, for most part, in an obscure manner, often by infer- 
ence rather than word. This must be taken to mean that those 
who wrote, with few exceptions, regard the question of the nature 
of the lichen settled. We may well inquire, then, what these modern 
botanists said concerning this matter, by word or by reasonably 
safe inference. Ten of them said nothing. Fourteen stated in 
more or less certain fashion that lichens are fungi, and 18 appear 
to believe that lichens are colonies of algae and fungi, or dual 
organisms. This re.sult, surprising as it is, demonstrates that 
some form of the dual hypothesis is still much alive, at least in 
the phraseology used by botanists in writing about lichens, and 
that the much discussed and vexing problem of the nature of 
lichens is by no means settled. 
In the present condition of affairs, it is difficult for most 
botanists to write a full page about lichens without contradicting 
any position taken, unless it be one not far removed from the 
traditions regarding these plants. As a whole, the replies quoted 
in Mycologia are as consistent as anything that has appeared on 
the subject; yet it would be rash for one who has examined the 
statements carefully to assume that he is certain that all of these 
botanists said what they intended. Indeed, some of the replies 
say that lichens are dual organisms, but should be distributed 
among fungi. Those who replied thus either believe that lichens 
are fungi, or that the fungi of the dual organisms should be dis- 
tributed. But they said neither of these things. One botanist 
who believes that the lichen is a fungus said positively in his 
reply that it is a dual organism. A few committed the too com- 
mon inconsistency of stating that lichens are both dual organisms 
