SUPPLEMENTARY NOTES 305 



Physarum lilacinum Sturgis & Bilgram, 1917 (p. 68), is preempted 

 by P. lilacinum Fries, 1829, universally recognized as applying to 

 Badhamia lilacina (Fr.) Rost. Known thus far only from the two col- 

 lections referred to by the authors, if found to be constant it must 

 receive a new name. 



Didymium complanatum (Batsch) Rost., 1875 (p. 107), is preempted 

 by D. complanatum Schrad., 1797, which may possibly refer to a 

 sessile phase of D. melanospermum (Pers.) Macbr., as Lister suggests, 

 or to something quite different. It is also preempted by Fuckel's use 

 of the binomial in 1869 for what is usually called Diderma radiatum 

 (L.) Morg. (p. 136). 



Tubifera stipitata (Berk. & Rav.) Macbr. (p. 233), is based on 

 Licea stipitata Berk. & Rav. 1860. But DeCandolle had used that 

 combination in 1815 for Didymium squamulosum, hence the next name 

 in point of priority, namely Licea microsperma Berk. & Curt. 1873, 

 should furnish the specific epithet, unless the commonly used name be 

 conserved. 



Oligonema nitens (Lib.) Rost. 1875 (p. 279) is based on Trichia 

 nitens Libert, 1834. But Trichia nitens Persoon, 1796, applies to a 

 different species, perhaps T. favoginea. The next oldest name is 

 Physarum schweinitzii Berk., 1873, which would provide the valid spe- 

 cific name according to a strict application of the rules. Nitens is 

 generally used, is eminently suitable and might well be conserved. 



H. C. Gilbert has recently made a careful study of Ceratiomyxa 

 under the direction of the junior author (Thesis, State Univ. Iowa, 

 1933) and concludes that the so-called spore is homologous with the 

 sporangium of many of the Myxogastres, while the sporophores are 

 equivalent to the hypothallus. He shows that germination of the 

 4-nucleate spore takes place by the gradual emergence of the proto- 

 plast, which expands and remains in globose or slightly irregular form 

 for up to an hour, becoming transformed into an elongated "thread" 

 phase which may persist for several hours. The globose shape is 

 again assumed and the nuclei become grouped in regular tetrahedral 

 fashion. Cleavage occurs and four uninucleate segments are formed 

 directly. Each segment now divides into two, so that eight cells are 

 present in the group, each of which develops a rlagellum. The swarm- 

 cells break away from the groups and swim singly, increasing some- 

 what in size, but give no evidence of division. Eventually fusion of 

 swarm-cells occurs. This may involve two or more swarm-cells, as 

 in Reticularia, but nuclear fusion is always between pairs of nuclei 

 of unlike reaction. In Ceratiomyxa, this unlikeness is distinctly mani- 



