246 PovaAH: A CRITICAL STUDY OF 
suivant que, dans le premier, le filament sporangifére est doué ou 
non d’accroisement intercalaire, qu’il est élancé ou trapu, suivant 
que, dans le second, le ramification s’opére en grappe ou en cyme, 
chacun de ces deux groupes se partage 4 son tour en deux sections. 
La monographie de genre Mucor et la description détaillée des 
nombreuses espéces qui le constituent est donc un travail d’assez 
longue haleine, qui doit faire l’objet d’une publication spéciale.”’ 
Schréter (1889) did not recognize Circinella, Rhizopus, and 
Spinellus as genera, but regarded them as subgenera under Mucor. 
Under his subgenus Eumucor, which was the genus as we now con- 
sider it, he gave but seven species, which are reduced to five when 
considered from our present knowledge of the genus. In Engler 
and Prantl’s Die natiirlichen Pflanzenfamilien (1892) Schréter 
still retained his all toocomprehensive genus Mucor, having added 
a fifth subgenus Pirella. 
Saccardo (1888) included descriptions of some seventy-eight 
species of Mucor, of which less than ten are now recognized as 
authentic species of Mucor. His only separation, or attempt at 
such, was a division into two groups, the first of which contains 
those forms in which the sporangia are slightly colored at maturity; 
the second, those which have hyaline sporangia at maturity. 
Under the first division he included a subdivision containing forms 
with ovoid spores. 
Fischer (1892) was the first to monograph the genus Mucor, 
giving twenty-one species with an analytical key. He first 
divided them into three sections, according to whether they were 
simple, monopodially or sympodially branched. These he again 
divided: the first section was subdivided according to the nature 
of the turf—whether peiseens erect or soon collapsing; the 
second and third secti divided according to their method 
of branching. Fischer, referring to his key, says that inasmuch 
as the species have not been studied thoroughly, ‘die folgende 
Zusammenstellung kann deshalb nur als eine provisorische betracht 
werden.”’ 
Schostakowitsch (1896, 1897, 1898), in his studies on the 
Siberian mucors, found nine species, seven of which were new to 
science. He found that Mucor Mucedo and Mucor racemosus, 
which were supposed to be of common occurrence throughout 
the world, grew seldom if at all in Siberia. - 
