312 AQUA TIC PH YCOM YCETES 



the sporangia of the American and British forms differ slightly in shape, 

 the former being spherical or subspherical, the latter more urceolate, 

 they agree in being attached to the host cell by short digitate rhizoids. 

 Couch states that the resting spore is surrounded by a gelatinous 

 sheath. This has been interpreted in the British fungus as wall material. 

 Couch discussed his fungus under the name Rhizophydium minimum 

 (Schroeter) Fischer, but it differs markedly from that species and 

 from other members of the genus in the character of its endobiotic 

 system. Further study may possibly show the fungi on Bumilleria and 

 Spirogyra to be distinct. 



? Rhizophydium sp. Karling 

 Amer. J. Bot., 33: 331, figs. 19-22. 1946 



Sporangia broadly or narrowly pyriform, rarely sessile, typically 

 borne at the tip of a slender, tapering stalk 10-50 \x in length, whose 

 distal end forms a sparse rhizoidal system within the substratum, with 

 a single terminal discharge pore; zoospores spherical with a single oil 

 globule; other characters unknown. 



Parasitic on the soma and cysts of a stalked protozoan, angiosperm- 

 pollen bait, Brazil. 



On Microscopic Animals 



? Rhizophydium leptophrydis Scherffel 

 Arch. Protistenk., 54: 172, pi. 9, fig. 9. 1926 



Sporangium sessile, very broadly pyriform, with a prominent broad 

 conical subapical protrusion (papilla?), 24 u, high by 21 \i in diam- 

 eter, the protrusion 10 [jl in diameter at the base by 5 \x high, wall 

 thin, smooth, colorless; rhizoidal system, zoospores, and resting spore 

 not observed. 



On the zoocyst of the vampyrellan Leptophrys vorax, Hungary. 



Differing from Rhizophydium vampyrellae (Dang.) Minden in having 

 a pyriform rather than a spherical sporangium. 



