CHYTRIDIALES 203 



In Zygogonium, sp., Scherffel (Joe. cit.), Hungary; Tetmemorus bre- 

 bissonii, Canter (1949c: 73, figs. 3-4, pi. 9, figs. 1-3), Great Britain. 



The species differs from Micromyces cristata in having a smooth- 

 walled prosorus and in forming more segments in the sorus. Scherffel's 

 figure of M. fischeri bears a close resemblance to his figure (fig. 76) 

 of M. cristata. 



Micromyces zygnaemicola (Cejp), comb. nov. 



Micromycopsis zygnaemicola Cejp, Bull. Internat. Acad. Sci. Boheme, 

 42 (3): 2, pi. 1, figs. 5-10; pi. 2, figs. 3-4. 1933 (separate). 



Prosorus spherical and 10-13 jjl in diameter or ellipsoidal and 9-10 

 by 12-13 [x, with a thickened smooth wall, discharge tube 3-4 [j. in 

 diameter, long; sorus nonsessile, borne at the tip of the discharge tube, 

 spherical, 13-15 u. in diameter, with a somewhat thickened brownish 

 wall covered by short blunt spines; soral wall at maturity splitting 

 along three sutures into three tetrahedral portions; sporangia spherical 

 or nearly so, thin-walled; zoospores and resting spore not observed. 



Parasitic in Zygnema stellina, Germany. 



Micromyces oedogonii (Roberts), comb. nov. 



Micromycopsis oedogonii Roberts, Trans. Brit. Mycol. Soc, 36: 320, 

 figs. 1-12, pi. 17. 1953. 



Prosorus mostly spherical, 14-30 [j. in diameter, smooth- walled with 

 greyish brown contents, causing swelling of newly formed host cells, 

 discharge tube cylindrical, 2—13 [x long, not extending beyond the host 

 wall; sorus epibiotic, sessile, spherical, the wall brownish and covered 

 with short blunt spines, soral wall at maturity splitting into a series 

 of polygonal plates, the bases of seven to fifteen pyramidal otherwise 

 thin-walled sporangia; zoospores of one type only, about fifty in a 

 sporangium, subspherical, 2 \x in diameter, with a colorless droplet 

 and single flagellum. Resting spores not observed. 



Parasitic in vegetative cells of Oedogonium sp., Great Britain. 



This species occurs in great abundance on Oedogonium but has not 

 been found on associated Oedogoniaceae or Conjugatae. It differs 

 from other members of Micromyces in its host and from its closest 



