ZYGOGONIUM 69 



14. Zygogonium stephensiae nom. nov. Trans. Amer. Micros. 

 Soc. 53, p. 208, PI. 17, Fig. 4. 1934 (as Zygnema stephens- 

 iae Transeau). 



Vegetative cells 22-29 a<. ^ 60-120 (-160) ;".; conjugation scalariform; 

 zygospores in the tubes, mostly globose 37-46 /u, in diameter, or ovoid 

 32-43^1. X 46-54 /x; median spore wall yellow-brown, densely punctate. 

 The sporangium wall is of 2 layers — the outer is the tube wall and the 

 inner is formed immediately after union of the gametes and completely 

 encloses the spore. The polar ends of the outer wall are of cellulose; the 

 middle part is of pectose. At maturity the pectose part may change to 

 pectic acid and disappear, and leave a collar at each pole of the sporan- 

 gium. The inner wall has an equatorial suture and the spore is released 

 by separation of the 2 hemispheres at this suture. The empty hem- 

 ispheres remain attached to the gametangial wall. (PI. XLI, Figs. 1-5.) 



United States: Pennsylvania, Roaring Branch, on wet sandstone cliffs, 

 September 21, 1933. 



Africa, Cape Colony, Cape Flats (E. Stephens Coll.), November 24, 

 1927. 



Cylindric akinetes make up entire filaments in one of the collections. 

 Akinetes have a length about equal to the diameter of the filament. 



List of Species of ZYGOGONIUM with Numbers 



capense (Hodgetts) Transeau 1933 6 



ericetorum Kiitzing 1843 i 



exuvielliforme Jao 1935 11 



hansgirgii (Schmidle) Transeau 1933 4 



heydrichii (Schmidle) Transeau 1933 9 



indicum (Randhawa) Transeau 1951 13 



l{iimaoense Randhawa 1940 7 



mirabile (W. & G. S. West) Transeau 1933 2 



pectosum Taft 1944 3 



plal{ountiosporum Jao 1935 12 



punctatum Taft 1944 8 



sinense Jao 1935 10 



stephensiae Transeau 1951 14 



tcdguppense Iyengar 1932 5 



