THE MYXOMYCETES 



Subclass EXOSPORE^ RosL 



Versuch2. 1873. 



Fructification composed of stalk-like, membranous, columnar, sim- 

 ple or branching sporophores or sometimes pore-like folds. Spores 

 white, stalked, borne superficially on the surface of the sporophores. 

 A single genus: 



Ceratiomyxa Schroeter 



in Engler & Prantl, Die nat. Pflanzenfam. 1 (i) : 16. 1889. 

 Ceratium Alb. & Schw., Consp. Fung. 358. 1805, non Shrank 1793. 



Sporangia none; spores superficial, colorless, on erect papillae or 

 branches or on the inside of minute depressions or pits, each spore 

 surmounting a delicate pedicel or stalk. Mature spore 4-nucleate, on 

 germination giving rise to a rounded amoeboid body, which, after 

 another nuclear division becomes transformed into eight flagellated 

 swarm-cells. Plasmodium inhabiting sodden wood, emerging to form 

 the fructification. 



The spores, in manner of formation and of germination, differ widely 

 from those of the other genera, with which their homologies seem ob- 

 scure. It has been suggested that the pedicels represent incipient 

 stipes; the spores primitive or simplified sporangia. 



Several species have been described but they all seem to merge 

 into each other and thus to be variants of a single species, too incon- 

 stant to deserve even varietal recognition for the most part, although 

 in deference to custom the varieties are here listed. 



Ceratiomyxa fruticulosa {Muell.) Macbr. 



N. A. Slime-Moulds 18. 1899. 

 PL I, Figs. 1, 2, 3, 4, 5. 



1777. Byssus fruticulosus Muell., Fl. Dan. 6 : 718. 



1778. Tremella hydnoidea Jacquin, Misc. 1 : 145. 

 1783. Clavaria puccinia Batsch, Elench. Fung. 139. 



1791. Clavaria byssoides Bull, Champ. France 209, pi. 415, fig. 2. 

 1791. Puccinia byssoides (Bull.) Gmelin, Syst. Naturae 2 : 1462. 



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