316 AQUATIC PHYCOMYCETES 



gating within, filling the trichogyne and extending and expanding be- 

 yond it, terminating distally in a short tubular portion with a blunt 

 rounded apex, the whole body thus being unequally spindle-shaped, 

 up to 125 [x in length (average 80 [x) by 12 jjl in greatest diameter, wall 

 thin, smooth, colorless; rhizoids not observed; zoospores small, spher- 

 ical, 2 fx in diameter, with a minute colorless refractive globule and 

 a flagellum, emerging through a pore formed at the apex of the spo- 

 rangium; resting spore not observed. 



Parasitic on oogonia of Coleochaete puhinata, Germany. 



The zoospore gains access to the oogonium by swimming down the 

 open trichogyne. The developing fungi, of which as many as four 

 attack a single egg, then consume the entire contents of the oosphere, 

 leaving only a small amount of reddish-brown residue. 



Whether or not this is a species of Olpidium, as Schroeter has sup- 

 posed, depends upon the interpretation of the position of the sporan- 

 gium and the possible absence of rhizoids. Fischer and Minden con- 

 sider the body of the fungus to be extramatrical in the already opened 

 oogonium. The apparent lack of a rhizoidal system even in nearly 

 empty oogonia, however, appears to strengthen Schroeter's inter- 

 pretation. New observations will be necessary before a final generic 

 disposition can be made. 



? Rhizophydium hormidii Skvortzow 

 Arch. Protistenk., 51 : 430, text fig. 5. 1925 



Sporangium narrowly clavate or curved and fusiform, 5.7-7 \i long 

 by 1.5-2 (j. in diameter, wall thin, smooth, colorless; rhizoids delicate; 

 zoospores one or two, 1 u. in diameter, with an oil droplet and a single 

 flagellum; resting spore not observed. 



On Hormidium flaccidum, Mougeotia viridis, Manchuria. 



Neither the description nor the figures are adequate enough to 

 characterize this species properly. 



REJECTED SPECIES OE RHIZOPHYDIUM 



* Rhizophydium microsporum (Nowak.) Fischer 

 Rabenhorst. Kryptogamen-Fl., 1 (4): 97. 1892 



