176 AQUATIC PHYCOMYCETES 



the Lagenidium parasite only in the fact that the zoospores had a single 

 basal refractive droplet and exhibited a swimming, not a hopping, 

 type o\~ movement. 



Because of the fact that the fungus sporangium completely fills the 

 host cell it is referred to Rozella, even though the formation of a pro- 

 nounced discharge tube appears rare among members of the genus. 



Rozella marina Sparrow 



Mycologia, 30: 377. 1938 



Pleolpidium marinum Sparrow, Biol. Bull., 70: 256, figs. 32-33. 1936. 



Sporangium spherical, completely filling the enlarged host spo- 

 rangium, 30-45 \x in diameter, at maturity forming from one to three 

 pores, through which the zoospores are discharged; zoospores ellip- 

 soidal, 3 [i long by 2 [x in diameter, posteriorly uniflagellate, without 

 globules; resting spore not observed. 



Parasitic in the sporangia of Chytridiumpolysiphoniae, United States. 



Rozella septigena Cornu 



Ann. Sci. Nat. Bot., V, 15: 163, pi. 6. 1872. Non Fischer, Jahrb. wiss. Bot., 

 13: 321, pi. 14, fig. 19, pi. 15, figs. 20-28. 1882 



(Fig. 12 H-I, p. 124) 



Sporangia possibly formed by successive fractionation of one thallus, 

 in transversely or obliquely walled-off segments of the sometimes 

 s]iglul\ swollen host hyphae which they completely fill, with from one 

 to several discharge papillae; zoospores minute, numerous, arched, 

 posteriorly uniflagellate, without globules; resting spore spherical, 

 with a slightly thickened wall covered with short tenuous spines, 

 brownish, with dense contents, formed in spherically swollen short 

 lateral branches of the hyphae, which are continuous with the main 

 axis or separated from it by a cross wall, germination not observed. 



Parasitic in Achlya racemosa, A. polyandra, Saprolegnia spiralis, 

 Cornu (loc. cit.), France; Saprolegnia dioica, Pringsheim (1860:205, 

 pl. 22, tigs. 1-6), Germany; Saprolegnia sp., Cejp (1934: 228, fig. 4), 

 Czechoslovakia. 



The fungus o\' Sorokin (1883:25, fig. 25) in Achlya racemosa in 



