SPIROGYRA 163 



scalariform; tubes formed by both cells; reproduction by zygospores 

 and aplanospores; zygospores ovoid, 29-35 /u ^ 44~73'"'l aplanospores 

 ovoid, 29-32 /i. X 38-42 /x; median wall punctate, yellow at maturity. 

 (PI. XXIV, Fig. 5.) 



China, Szechwan, November 15, 1933. 



46. Spirogyra asiatica Czurda 193 1. Susswasserflora Mitteleu- 



ropa. 9, p. 185. 1932. 



Vegetative cells 46-51 /x x ioo-i6o;u,, with plane end walls; i chro- 

 matophore (rarely 2); conjugation lateral; tubes formed by both cells; 

 fertile cells enlarged; zygospores ovoid, 60-65 ju. x 80-120 /a; median spore 

 wall dark brown, and minutely granulose; suture more or less prom- 

 inent. (PI. XXIV, Fig. 6.) 



Central Tibet, altitude 17,000 feet. 



47. Spirogyra lagerheimii Wittrock 1889. In Wittrock and Nord- 



stedt Algae Exsiccatae, Nos. 961 and 962. Bot. Notiser 

 1889. p. 165. 



Vegetative cells 25-33^1 x 75-1 50 m, with plane end walls; i chro- 

 matophore, usually narrow, making .5 to 4 turns; conjugation scalar- 

 iform and lateral; tubes formed by both cells; fertile cells cylindric or 

 enlarged; zygospores ellipsoid with more or less pointed ends, 25-38 /a x 

 50-100 /a; median spore wall yellowish-brown, finely punctate. (PI. 

 XXIV, Fig. 7.) 



United States: Illinois; Ohio; Massachusetts; New Hampshire. 



Sweden; Germany; Latvia; Finland. 



In the many collections seen, the chromatophores were uniformly nar- 

 row and formed open spirals. 



48. Spirogyra taftiana Transeau 1944. Ohio Jour. Sci. 44, p. 243. 

 Vegetative cells 18-25 /a ^ 50-96 ;"■, with plane end walls; i chro- 



matophore, making 2-4 turns in the cell; conjugation scalariform; tubes 

 formed by both gametangia; receptive gametangia enlarged or fusi- 

 form-inflated; sterile cells often bulliform; zygospores ellipsoid, 24-34 /a 

 x 42-80,11; median wall distinctly and densely punctate; pits more or 

 less angular, yellow. (PI. XXIV, Fig. 8.) 



United States: Texas, Huntsville (Taft Coll.). 



Named for C. E. Taft, The Ohio State University, author of many 

 papers on fresh-water algae. 



49. Spirogyra perforans Transeau 1934. Trans. Amer. Micros. 



Soc. 53, p. 228, PI. 21, Fig. 57. 

 Vegetative cells 14-18 ft x 72-120^1, with plane end walls; i chro- 

 matophore, making 3 to 6 turns; conjugation scalariform; tubes formed 



