170 ZYGNEMATACEAE 



73. Spirogyra hyalina Cleve 1868. Nova Acta Reg. Soc. Sci. 



Upsali. Ser. 3, 6, p. 17, PI. 3, Figs. 1-6. 



Vegetative cells 45-60 /a x 80-240 y^i, with plane end walls; chro- 

 matophores, 2, 3, or 4, making ,5 to 3 turns; conjugation lateral or 

 scalariform; tubes formed by both gametangia; fertile cells cylindric, 

 or slightly inflated; zygospores ellipsoid, more or less pointed, 45-60/^ x 

 60-130 m; median spore wall brown, smooth; aplanospores similar, 

 somewhat smaller. (PI. XXVI, Figs. 11-12.) 



United States: Iowa; Mississippi. 



Sweden; Puerto Rico; India; China. 



Cleve's figures show the characteristic long conjugating tubes. In lateral 

 conjugation the form of the tube is almost unique. 



74. Spirogyra pseudoneglecta Czurda 1932. Siisswasserfiora Mit- 



teleuropa. 9, p. 194. 



Vegetative cells 55-60^1 x 130-240 m, with plane end walls; 3 chro- 

 matophores; conjugation lateral and scalariform; tubes formed by both 

 gametangia; fertile cells cylindric or slightly swollen; zygospores ellip- 

 soid, 50-52 /A X 95-100 /x; median spore wall reddish-brown, smooth. 

 (PL XXVI, Figs. 13-14.) 



Moravia. 



75. Spirogyra columbiana Czurda 1932. Siisswasserfiora Mittel- 



europa. 9, p. 190. 



Vegetative cells 48-54 /a x 90-1 80 ju, with plane end walls; chromato- 

 phores (i-)3; conjugation scalariform; tubes formed by both gam- 

 etangia; fertile and sterile cells cylindric; zygospores ellipsoid, about 

 50 /i X 70 /x; median spore wall smooth, yellow-brown, suture distinct. 

 (PI. XXVI, Fig. 15.) 



South America, Colombia; South Africa; lava. 



76. Spirogyra angolensis Welwitsch 1897. Jour. Bot. 35, p. 41. 

 Vegetative cells 49-62 jn x 60-200 i^, with plane end walls; 2 or 3 



chromatophores, making 2 to 3 turns; conjugation scalariform; tubes 

 formed by both gametangia; fertile cells cylindric or enlarged; zygo- 

 spores ellipsoid with somewhat pointed ends, 52-57 m x 84-100 m; median 

 spore wall smooth, yellow. 



United States: Iowa (Tiffany Coll.). 



South Africa, Angola; China, Yunnan. 



77. Spirogyra welwitschii W. & G. S. West 1897. ]our. Bot. 35, 



p. 41. 



Vegetative cells 65-75/ii x 40-150^1, with plane end walls; 2 (rarely 

 3) chromatophores, making i to 2 turns; conjugation scalariform; tubes 



