CHYTRIDIALES 351 



arising from a subsporangial apophysis; zoospores spherical, 3 \x in 

 diameter, with a colorless globule, escaping through a sessile or slightly 

 elevated apical pore; resting spore not observed. 



In cells of Nitella tenuissima, France. 



Fischer and Minden think that this species forms epibiotic sessile 

 sporangia. Dangeard does not describe their position in relation to the 

 host cell. From the fact that comparison is made in the description 

 with Diplophlyctis intestina it is very probable that the fungus is entirely 

 endobiotic and hence not a species of Phlyctochytrium, but rather of 

 Diplophlyctis. 



Fischer and Minden also believe the swellings on the surface of the 

 sporangium to be quiescent zoospores. Scherffel (1925b: 48), however, 

 suggests that they may be male cells similar to those found in some 

 species of Rhizophydium. 



? Phlyctochytrium desmidiacearum Dangeard 

 Le Botaniste, 28: 196, pi. 19, figs. 1, 3-9, 11-20. 1937 



Sporangium sessile, narrowly to broadly ovoid or somewhat nar- 

 rowly urceolate, with an apical collarette of not more than four bipar- 

 tite shallowly cleft prominent teeth, wall thin, smooth, colorless; 

 rhizoids branched, arising from a main axis at the base of a broadly 

 fusiform or spherical subsporangial apophysis; zoospores spherical, 

 2-3 [i in diameter, with a colorless eccentric globule and a long flagel- 

 lum, escaping through a large apical pore; resting spore asexually form- 

 ed, extramatrical, generally sessile, spherical, 20-25 (jt in diameter, 

 with a thickened smooth colorless wall, contents with a large central 

 vacuole surrounded by numerous small globules, endobiotic system 

 like that of the sporangium but usually with a much smaller apophysis, 

 germination not observed. 



On Closterium ehrenbergii and related species and on Netrium digitus, 

 France. 



Since observations on the precise number and arrangement of the 

 teeth were incomplete the species cannot be adequately defined. It is of 

 interest, however, because of the resting spores, this being probably the 



