LAGENIDIALES 953 



intricate!, France; Trailliella intricate, Falkenbergia rufolanosa, Aleem 

 (1953: 10, figs. 17-18), Sweden. 



This species is here retained in Olpidiopsis rather than placing it in 

 Pseudolpidium with the other Olpidiopsis -like forms which lack resting 

 spores. A new combination seems unnecessary. 



RECENTLY DESCRIBED TAXA ' 



Olpidiopsis magnusii J. and G. Feldmann 

 Rev. Mycologique, 20: 243, fig. 4. 1955 



Sporangia spherical, up to 45 \i in diameter, singly or up to five in the 

 inflated rhizoid of the host; zoospores numerous, reniform, 5\i long, 

 with two lateral flagella, escaping and swimming away through a single 

 cylindrical tapering discharge tube which penetrates the host wall. 



In terminal cells of rhizoids of Ceramium flabelligerum, J. and G. 

 Feldmann (loc.cit.), France; Ceramium spp. Magnus (1875). 



J. and G. Feldmann identify their fungus with the one Magnus ( 1872, 

 1875) figured in the rhizoids of Ceramium spp. The Feldmanns believe 

 that it is a different form from the one Magnus found in the cortical cells 

 and axillary cells, which they consider belongs in Eurychasmidium (see 

 p. 822). 



Olpidiopsis myzocytia Rieth 

 Die Kulturpflanze, 2: 180, fig. 10. 1954 



Sporangia mostly one, sometimes up to four in a segment of the host ; 

 primary zoospores five to six, encysting at the orifice of a short, isodia- 

 metric discharge tube, secondary zoospores with two nearly equal flagella 

 and pulsating vacuole; resting spore sexually formed, the male gamete 

 passing through a pore into the receptive thallus in which a smooth, 

 thick-walled plerotic oospore (7)-9, 5-( 12);jl, is formed whose germina- 

 tion is not known. 



Parasitic in segments of the thallus of Myzocytium proliferum, 

 Germany. 



Strongly resembling a Pythiella allied to P. besseyi (p. 814). 



1 Not included in the key. 



