ZYGNEMA 27 



55-60 /a; median spore wall brown, scrobicialate; pits about 3/^ in diam- 

 eter. (PI. Ill, Fig. 8.) 



United States: Illinois. 



20. Zygnema giganteum Randhawa 1936. Proc. Indian Acad. Sci. 



4, p. 241. 



Vegetative cells 40-48 /a x 56-90 /a; reproduction by zygospores and 

 aplanospores; conjugation scalariform; zygospores formed in the con- 

 jugating tubes; zygospores ovoid to globose, 48-64 /^ x 56-70 /a; median 

 wall yellow-brown, of 2 layers, of which the outer is undulate pitted and 

 the inner smooth or granulate. The other 2 walls are transparent. 

 Aplanospores cylindric, filling the cells, with walls similar to those of 

 the zygospores, 38-48 /a x 45-72 ju-. (PI. Ill, Figs. 9-10.) 



India, Kapurthala State, Punjab, March, 193 1. 



This description is modified from the original on the basis of specimens 

 kindly sent by Mr. Randhawa. Associated with this species in the original 

 collection is an anisogamous species with very peculiar conjugating tubes, in 

 that a ring of pectic material surrounds the tube at the point of union. This 

 is indicated by Randhawa's figures. However, there are no ripe spores in 

 the material that I have seen and because of the smaller zygospores I believe 

 it is a distinct and unnamed species. 



21. Zygnema gedeanum Czurda 1932. Susswasserfiora Mittel- 



europa. 9, p. 115, Fig. 118. 



Vegetative cells 13-15 j^a x 32-34 ;u; conjugation lateral; zygospores 

 formed in the conjugating tubes, ovoid, 22-24 /a ^ 3P~?P-l^''> median spore 

 wall blue to blue-black, thick, pitted; pits about im in diameter. (PI. Ill, 

 Figs. 11-12.) 



Java. 



22. Zygnema cyanosporum Cleve 1868. Nova Acta Reg. Soc. Sci. 



Upsali. 6, p. 28, PI. 8, Figs. 6-8. 



Vegetative cells about 20-22/1. x 40-180/t; conjugation scalariform; 

 zygospores formed in the conjugating tubes, globose, rarely quadrate- 

 globose, 30-40 ju. in diameter; median spore wall blue, thick, smooth. 



United States: Michigan. 



Greenland; Sweden; Finland; India; South Africa. 



23. Zygnema czurdae Randhawa 1936. Proc. Indian Acad. Sci. 



4, p. 239. 



Vegetative cells 20-27 /a ^ 30-100/1, with 2 chromatophores; con- 

 jugation lateral and scalariform; spores formed in the tubes; during 

 lateral conjugation the intergametangial wall sphts and the gametangia 

 are connected only by the enlarged tubes; in scalariform conjugation the 



