CHYTRIDIALES 313 



SECTION III 



On Fresh-Water Algae 



? Rhizophydium septocarpoides H. E. Petersen 

 Bot. Tidsskrift, 29: 420, fig. 24d. 1909; Ann. Mycologici, 8: 552, fig. 24d. 1910 



Sporangium resting on a short needle-like extramatrical stalk, ob- 

 pyriform, 8—16 {jl high, the basal part distinctly cylindrical, wall thin, 

 smooth, colorless; rhizoids poorly developed, once-branched, arising 

 from a main axis which is continuous with the short extramatrical 

 stalk; zoospores and resting spore not observed. 



On Closterium spp., Denmark. 



This incompletely known species resembles a small form of Chy- 

 tridium versatile. Until spore discharge is described it cannot be placed 

 generically with any certainty. Sparrow (1936a: 437, fig. 3t) has de- 

 scribed a fungus on diatoms in England which resembles Petersen's 

 species very closely in size and shape. Here again, however, no spore 

 discharge was witnessed. 



? Rhizophydium sp. Karling 

 Bull. Torrey Bot. Club, 76: 360, figs. 53-59. 1949 



Sporangia broadly obpyriform or clavate, 15-22 x 24-30 u,, with a 

 tapering, curved base and broad, almost flat apex; rhizoids short, 

 broad in diameter, branched, occasionally reduced to digitate struc- 

 tures; other characters unknown. 



Parasitic on Chytriomyces fructicosus, United States. 



Probably Rhizophydium utricular e Uebelmesser (1956). 



SECTION IV 



On Fresh-Water Algae 



? Rhizophydium asterosporum Scherffel 

 Arch. Protistenk., 53: 17, pi. 1, figs. 30-39. 1925 

 Sporangium sessile, short cylindrical, pouchlike, or somewhat tubu- 



