282 AQUATIC PHYCOMYCETES 



Rhizophydium brauni (Dang.) Fischer 

 Rabenhorst. Kryptogamen-Fl., 1 (4): 94. 1892 



Chytridium brauni Dangeard, Bull. Soc. Bot. France, 34: xxii. 1887; Le 

 Botaniste, 1 : 57, pi. 3, fig. 11. 1889. 



Sporangium sessile on the gelatinous envelope of the algal colony, 

 narrowly pyriform or ovoid, the attenuated apex often slightly curved, 

 wall stout, smooth, colorless; rhizoid a long slender unbranched (?) 

 filament which penetrates the algal cells; zoospores from fifteen to 

 twenty-five, spherical, 2 u. in diameter, with an eccentric colorless glob- 

 ule and a long flagellum, escaping through an apical pore formed 

 upon the deliquescence of a papilla; resting spore not observed. 



Parasitic on Apiocystis brauniana, France. 



If subsequent investigations show that the rhizoid is unbranched 

 within the algal cells and does not taper, then the species might better 

 be placed in Phlyctidium. The sporangia are described by Dangeard 

 as ovoid, but from the figures they distinctly appear narrowly pyri- 

 form. Rhizophydium simplex seems doubtfully distinct from this species. 



Rhizophydium simplex (Dang.) Fischer 

 Rabenhorst. Kryptogamen-Fl., 1 (4): 101. 1892 



(Fig. 17 S, p. 228) 

 Chytridium simplex Dangeard, Le Botaniste, 1 : 60, pi. 3, figs. 18-20. 1889. 



Sporangium resting directly on the host cell or on the surface of 

 the gelatinous sheath, narrowly pyriform, 8-1 5 [x long by 6-7 jj. in 

 diameter, prolonged apically into a slightly bent tube, wall thickened 

 a little, smooth, colorless; endobiotic part consisting of an unbranched 

 rhizoid which penetrates the protoplasm of the host; zoospores few to 

 from thirty to forty, ellipsoidal or spherical, 1.5-3 \l in diameter, with 

 a colorless basal globule and a long flagellum, emerging through a 

 small pore formed at the tip of the sporangium; resting spore spherical, 

 6-7 [jl in diameter, with a thick smooth colorless wall, rhizoidal system 

 like that of the sporangium; germination not observed. 



Parasitic on cysts of Cryptomonas sp. in culture jar, Dangeard Uoc. 

 cit.), France; dead colonies of Pandorina, Sparrow (1933c: 519), 

 United States; Spirogyra, Chlorococcwn (?), Sparrow (1936a: 439, 

 fig. 3 h-k), Great Britain. 



