136 MISSOURI BOTANICAL GARDEN. 
It has been recently well said that “reproduction by spores 
plainly decreased greatly when the symbiotic relationship 
was taken on, and the result has in all probability been 
a considerable physiological degeneration of the spores in 
the course of phylogenetic development.’”’ The lichens, un- 
like the fungi, have other methods of reproduction, and we 
must not lay too much stress on the structures of the largely 
abortive fruit when after all it is the thallus of a lichen 
that is unique,—and we are considering the classification of 
them and not of true fungi. 
In the present classification the thalline method has been 
followed. This should not blind one to the fact that the 
radial Teloschistes have undoubtedly their closest phylo- 
genetic relatives (as indicated by the spore) in the polari- 
bilocular Xanthorias, Placodiums, ete. Throughout this 
classification the fruit characters are given the first (Gym- 
nocarpales) and large importance,—but as in the Pha- 
nerogams their protophytic characters are not employed. 
Phylogenetically, probably, Usnea and Ramalina, Alectoria 
and Oropogon, are distinct, yet it seems hardly wise to sep- 
arate these radial and lecanorine genera. The inclusion of 
Teloschistes by M. Hue has been an innovation, rather than 
illogical. To introduce into the family, as the thalline ex- 
tremists have done, the lecidiene genus Roccella would be a 
vastly greater step ;—contradictory to the apothecial, as their 
inclusion with the Graphidinex has been to thalline affilia- 
tion. Medio tutissimus ibis. 
CHEMICAL CONSIDERATIONS, 
This family has been shown, particularly by the late Dr. 
W. Zopf,’ to produce several lichen acids. These have been 
used as aids in classification, though for them can be claimed 
comparatively little practical value. The following varieties 
have been attributed to the Usneacee: 
8 Die Flechtenstoffe, 1907. 
