1897.] The Polyphyletic Disposition of Lichens. 279 
of this, I might then cite Moeller (Flora 77 : 253, 1893), who 
shows conclusively that the thelephoroid fungus represented 
by the three lichen genera, Cora, Dictyonema, and Laudatea, 
may be, at the same time, a saprophyte, or a parasite upon two 
different genera of alge, i. e., a facultative parasite. For the 
ascolichens, Reinke contradicts his own statement that their 
fungal prototypes no longer exist (Pringh. Jahrb. 28:71, 87, 
135, 1895). The mere fact that he has been obliged to divide 
the genera Calicium, Bilimbia, Bacidia, Placographa, Melaspila 
and Arthonia into a series of lichen genera corresponding 
respectively to the above, and a series of “ myco-genera,” Myco- 
calicium, Mycobilimbia, Mycobacidia, etc., solely because certain 
fungi, having parasitized accidental algal cells, have lost their 
saprophytic habit, is conclusive. It is also admitted by the 
best mycologists that Biatoridium, Lecidea and Buellia can be 
distinguished from Biatorella, Patinella, and Karschia only 
through what can be called scarcely more than incipient par- 
asitism. More than this, Buellia myriocarpa, as Reinke him- 
self admits (Pringh. Jahrb. 28 : 98, 1895), is sometimes provided 
with gonidia, sometimes lacks them. It is then either a fungus 
or a lichen. This species is certainly a remarkable one, in 
that it belongs to two different and distinct subkingdoms, or 
at least classes! Were cumulative evidence needed, the re- 
peated artificial synthesis and analysis of lichens would be 
more than sufficient to discredit Reinke’s statement, notwith- 
standing his inability to appreciate the weight of these facts. 
It is a scientific truism that phylogeny is the science of prob- 
abilities. No thoughtful scientist should dream of demanding 
absolute proof in general phylogenetic problems. In discussing 
questions of phylogeny, when the ultimity of probability is 
reached, except in the rarest cases, argumentation must cease. 
As for hymenolichens, we may regard Moeller’s careful re- 
searches as, comparatively speaking, absolute proof of their 
direct and recent derivation from the Thelephoracex. For the 
ascolichens, enough has been said to demonstrate the conelu- 
sion toward which extreme probability points. 
“The attempts at the distribution of the lichens have been 
of an unsatisfactory nature.” It is by no means true that, to 
