146 



Mycologia 



Van Tieghem (55-56-57), in a series of papers dealing practi- 

 cally with the entire group of Zygomycetes, undoubtedly laid the 

 foundation for the later conception of simultaneous division. In 

 reference to Sporodinia, he writes as follows : " Le protoplasma 

 sporigene se separe d'abord en deux substances tres differente. 

 La premiere tou jours granuleuse, se condense en petites portions 

 polyedriques qui deviendront bientot autant de spores." 



Twenty years later Leger (34), in his very fully illustrated 

 thesis, dealing with fourteen species of Zygomycetes, quotes Van 

 Tieghem's reference to the manner of spore formation in Sporo- 

 dinia and adds : " En somme, ce passage montre d'une facon tres 

 exacte le developpement des spores dans ses traits principaux." 

 The discovery of cell-plates in the division of the cells of the 

 higher plants undoubtedly influenced the conclusions of many stu- 

 dents of spore formation. 



Strasburger (48-49) for Saprolegnia and Mucor mucedo, Biis- 

 gen (8) for the Saprolegniales, Phytophthora, Cystopus and 

 Mucor mucedo, Ward (59) for Phytophthora infestans, and Mau- 

 rizio for Ol'pidiopsis state that the cell-division in these forms is 

 by cell-plates. 



Fischer (19), studying spore formation in the sporangia of 

 Woronina, describes the process as follows : " der Zerfall des Spo- 

 rangiumplasma in eine der grosse desselben entsprechende Anzahl 

 anfangs polyedrischen Portionen, die zukiinftigen Schwarme." 

 Van Tieghem, as noted, refers to a condensation into polyhedral 

 portions. Fischer observes a breaking up into polyhedral masses. 

 It is interesting to note that the same author (Fischer (19)) re- 

 garded the spore plasm of Olpidiopsis and Rozella as suddenly 

 forming rounded spores. In the former case he writes : " Mit 

 einem male zerfallt das gesammte Inhalt in scharf umschriebene 

 rundliche Theilchen. . . ." In the latter case he states : " Plotz- 

 lich zerfallt nun in einem gegebenen momente das Protoplasma in 

 eine menge rund umschriebenen Portionen die zukiinftigen Zoo- 

 sporen." Pringsheim (43-45) regards the spore formation as 

 occurring " unmittelbar " (directly) in Achlya prolifera, Olpidi- 

 opsis, Rozella, and Woronina. 



Strasburger (48) was perhaps the first to use the term, simul- 



