CHYTRIDIALES 309 



sitans, on the other hand, is directly parasitic on the sporangium of 

 R. goniosporum, or — a possibility not mentioned by Scherffel — on the 

 feeding or "vegetative" stage of the extraneous, cyst-forming organism. 

 Further observations, particularly on the nature of the endobiotic 

 system and on just what structure is penetrated by the zoospore of 

 Rhizophydium parasitans, will be necessary before this puzzle can be 

 solved. 



? Rhizophydium sp. Karling 



Amer. J. Bot., 33: 334, figs. 29-30. 1946 



Sporangium nearly spherical, with two subapical discharge papillae; 

 rhizoidal system much branched, arising from the tip of a central axis; 

 zoospores globose, with coarsely granular, nonrefringent contents, oil 

 globule lacking. 



On elm-pollen bait, Brazil. 



Said to differ from all other species of the genus in that its zoospores 

 lack a globule. 



On Microscopic Animals 



? Rhizophydium chrysopyxidis Scherffel 

 Arch. Protistenk., 54: 174, pi. 9, fig. 12. 1926 



Sporangium sessile, ovoid, 8 \i long by 6 a in diameter, with a pro- 

 longed apical beak and a narrow base, wall thin, smooth, colorless; 

 endobiotic part consisting of a short fairly thick unbranched tube 

 which terminates in a knob-shaped swelling; zoospores and resting 

 spore not observed. 



Attached to the mid-region or under part of the lorica of Chryso- 

 pyxis sp., Hungary. 



Possibly a species of Phlyctidium. 



On Unknown Substratum 



? Rhizophydium tranzschelii Jaczewski 



Opredelitel gribov I. Fikomitsety, p. 39. 1931 



Sporangium spherical, 39 \x in diameter, with a single opening; zoo- 

 spores 4-5 [jl long; resting spore spherical, 15 a in diameter. 

 Russia. 



