257 
Reinke’s Discussions of Lichenology.—IV, 
By ALBERT SCHNEIDER: 
IV. OUTLINES OF A COMPARATIVE MORPHOLOGY 
OF THE LICHEN THALLUS.* 
Numbers IV. and V. of Reinke’s papers treat of the same 
subjects, that is the polyphylogeny, relationships and comparative 
morphology of the genera. - 
The author considers the system of Tuckerman as being the 
nearest approach to a natural arrangement. Reinke’s system dif- 
fers in that the relative position of tribes as well as of the families 
and genera has been modified. While Tuckerman proceeded 
from the higher to the lower, Reinke bases his system on the re- 
verse arrangement. The author wishes to have it distinctly un- 
derstood that the proposed system is by no means perfect; it is 
Only an attempt at a natural arrangement of lichens based upon 
the very deficient data obtained from the study of the phyloge- 
netic history of these plants. 
The profuse illustrations accompanying the papers represent 
the Morphological characters of generic types. The illustrations 
of sections of the thalli and apothecia are more or less semi-dia- 
gTammatic, no attempt being made to give exact anatomical de- 
tails, which is rather to be regretted in a work otherwise so com- 
Plete. It seems also that the author has in many instances relied 
wholly upon the observations of others. 
V. THE NATURAL SYSTEM OF LICHENS.+ 
The author precedes the consideration of the arrangement of 
lichen groups by a lengthy theoretical discussion of the phylo- 
genetic relationship of the groups to each other and to fungi. 
Much of it is a repetition of what had been stated in preceding 
Papers. The same may be said of the general considerations of 
the sub-classes, families and genera. 
*Reinke, J. Skizzen zu einer vergleichenden Morphologie des Flechtenthallus. fas 
_ Jahrbiicher fur wissenschaftliche Botanik, 28: 70-150, 359-486. Pk tle ee 
tReinke, J. Das natiirliche Flechtensystem. Jabrbiicher fir wissenschalllche — 
Botanik, 29: 171-236. 1896. — oo ee a es 
