CHYTRIDIALES 343 



Phlyctochytrium dentatum (Rosen) de Wildeman 



Bull. Soc. Roy. Bot. Belg. (Mem.), 35: 46. 1896 



Chytridium dentatum Rosen, in Cohn, Beitr. Biol. Pflanzen, 4: 266, pi. 14, 



fig. 29. 1887. 

 Rhizidium den tatum (Rosen) Dangeard, Le Botaniste, 1:64. 1889. 



Sporangium sessile or occasionally stalked, somewhat cylindrical 

 or ovoid, with four apical bipartite prominent converging teeth, wall 

 thin, smooth, colorless; rhizoids delicate, branched, arising from sever- 

 al places on a spherical or subspherical subsporangial apophysis; 

 zoospores and resting spores not observed. 



On Spirogyra orthospira, Rosen (loc. cit.), France (Strasbourg); 

 Spirogyra sp., coll. Scherffel, Domjan (1936:43, pi. 1, figs. 96-97), 

 Berczi (1940: 83), Hungary. 



Rosen was unsuccessful in his attempts to inoculate Zygnema and 

 Oedogonium with this fungus. 



The species resembles Phlyctochytrium urceolare in the shape of its 

 sporangium, but differs in having four teeth rather than six. 



Minden (1915:344) uses the binomial Phlyctochytrium dentatum 

 (Rosen) Schroeter, but the combination was not actually used by 

 Schroeter when he established the genus. Fischer (1892: 110) calls it 

 PJuzidium dentatum (Rosen) Fischer. In a list of Hungarian fungi 

 Moesz (1938:72) uses the binomial Phlyctidium dentatum (Rosen) 

 Schroeter. Since no such combination was apparently ever made by 

 Schroeter, it is presumed that Phlyctidium was used in error for Phlyc- 

 tochytrium. 



Phlyctochytrium quadricorne (de Bary) Schroeter 

 Engler and Prantl, Naturlichen Pflanzenfam., 1 (1): 79. 1892 

 Chytridium quadricorne de Bary. See Rosen, in Cohn, Beitr. Biol. Pflanzen, 



4:266, pi. 14, fig. 28. 1887. 

 Rhizidium quadricorne (de Bary) Dangeard, Le Botaniste, 1 : 64. 1889. 



Sporangium sessile, broadly cylindrical or broadly ovate, 10-1 1 \l 

 high by 13 [jl in diameter, with a rounded or flattened base, bearing 

 an apical collarette of four solid upright deeply incised bipartite prom- 

 inent teeth, wall fairly stout, colorless; rhizoids present or absent, 



