2i8 ZYGNEMATACEAE 



254. Spirogyra nawashini Kasanofsky 1913. Berichte deutsch. 



hot. Ge sells. 31, p. 55, PI. 3. 



Vegetative cells 27-41 /x x 170-325/i, with replicate end walls; 2 

 (rarely i) chromatophores, with .5 to 1.5 turns; conjugation scalar- 

 iform; tubes formed by both gametangia; fertile cells fusiform, inflated 

 to 50-55 m; zygospores ellipsoid to cylindric-ellipsoid, 30-49^1 x 45-1 00 /j-; 

 median spore wall reticulate, yellow-brown. 



United States: Indiana (Ben Smith Coll.). 



Ukraine, Kiev; China, Nanking (Li Coll.); South Africa (Stephens 

 Coll.). 



255. Spirogyra tetrapla Transeau 1938. Amer. ]our. Bot. 25, 



p. 528, Fig. 6. 



Vegetative cells 30-40 /x, x 100-250 /n, with replicate end walls; i or 2 

 chromatophores, making 2 to 8 turns in the cell; conjugation scalar- 

 iform; tubes formed by both gametangia; fertile cells inflated, up to 

 66m; zygospores ellipsoid, 48-58 /j. x 68-88 /a; median wall of 2 layers, of 

 which the outer is thin and irregularly corrugate; the inner, finely 

 reticulate, yellow. (PI. XXXIX, Fig. 4.) 



United States: Illinois; Indiana; Ohio; Mississippi, 



256. Spirogyra reticulata Nordstedt 1880. Bot. Notiser 1880. 



p. 118. Wittrock and Nordstedt Algae Exsiccatae, No. 362. 



Vegetative cells 28-42 /li x 72-460 /j., usually with replicate end walls; 

 I to 3 (usually 2) chromatophores, making 2 to 4 turns; conjugation 

 scalariform and lateral; tubes formed by both gametangia; fertile cells 

 enlarged or inflated toward the middle to 48-60 /t; zygospores mostly 

 ovoid, 45-61 /A X 80-120 /i.; median spore wall yellow-brown, of 2 layers, 

 of which the outer is thin and wrinkled; the inner reticulate. (PI. 

 XXXIX, Fig. 5.) 



United States: Iowa; Oklahoma; Mississippi; eastward to Maine and 

 south to Florida. 



Brazil; Europe; China; India. 



This description is amended as to the median spore wall. This wall is 

 double in both specimens from Brazil upon which Nordstedl's description 

 is based and is likewise present in the American, European, and Chinese 

 specimens that I have examined. 



257. Spirogyra regularis (Cedercreutz) Krieger 1944. Rabin- 



horst's Kryptogamen flora. 13, p. 464. Acta Soc. pro 

 Fauna et Flora Fennica. 55 (2), p. 3. 1924. 

 Vegetative cells 21^32 /x x 110-380 m, with replicate end walls; 2 

 chromatophores, making 4 to 6 turns in the cell; conjugation scalar- 



