304 PovaH: A CRITICAL STUDY OF 
2. TAXONOMIC CHARACTERS 
As has already been stated in the taxonomic division of the 
work, the author has disregarded some of the usage of past writers 
in the compilation of his key and specific descriptions. This has 
been done only after careful consideration and the subsequent 
belief that, by so doing, matters might be simplified and put on a 
surer basis than heretofore. Fischer (1892) regarded the grouping 
of the genus Mucor into sections according to branching ‘‘nur als 
eine provisorische Zusammenstellung.”” Yet Lendner (1908), 
Hagem (1908), and Jensen (1912) use the same method of separa- 
tion, and as a result we find that there is considerable confusion 
and disagreement. To show this more clearly let us consider a few 
cases. Mucor strictus Hagem was placed by its author with the 
unbranched forms, but Lendner considers that it belongs in the 
Cymo-Mucor group and places it accordingly. Mucor sphaero- 
sporus Hagem and M. griseo-cyanus Hagem, although classed by 
Hagem in the Racemo-Mucor group, are transferred to the cymose 
group by Lendner. Mucor hiemalis Wehmer, which Hagem calls 
a Racemo-Mucor, is held by Lendner to belong to the unbranched 
forms. Mucor silvaticus Hagem, placed in the Cymo-Mucor 
group by its author, is transferred to the Racemo-Mucor group by 
Lendner. Thus it appears, not only that the terms racemose and 
cymose, as applied to the branching in this genus, are interpreted 
by different authors in various ways but also that authors are 
disagreed as to whether forms are to be considered as simple or 
branched. 
It has been the writer’s experience that a mucor which never 
possesses a branched sporangiophore is a rare occurrence; for a 
careful search of the culture will usually reveal some branches 
which are likely to be overlooked, since they are near the sub- 
stratum. Lendner (1908, p. 55) points out this difficulty. Prac- 
tically it amounts to the necessity of deciding whether or not 
branching, if found, is abnormal. The writer believes this to be 
too difficult, as his work on the group has proved. Thus this 
means of separation has been avoided in the key and descriptions 
which this work contains. 
Lendner (/.c.) describes the Racemo- Mucor group as follows: ‘‘The 
filament is early terminated by a sporangium, then branches arise 
