172 ZYGNEMATACEAE 



Vegetative cells 83-92 /x x 43-256 m, with plane end walls; 2-4 chro- 

 matophores, usually 3, making .5-2 turns in the cell; conjugation scalar- 

 iform; tubes formed by both gametangia; receptive gametangia cylin- 

 dric or slightly enlarged; zygospores mostly ellipsoid, 5^-79/^ x 83-128 /x; 

 all walls smooth; median wall yellow. (PI. XXVII, Fig. 3,) 



United States: Indiana, Sullivan County, September 10, 1936. 



Resembles S. setijormis but differs in chromatophore complement and 

 in the proportionately smaller spores. 



82. Spirogyra setiformis (Roth) Kiitzing 1845. Phycologia Ger- 



manica, p. 223. 



Vegetative cells 90-1 15 j". x 100-225 /i, ^^'^'^^ plane end walls; chro- 

 matophores 4, making .5 to 4 turns in the cells; conjugation scalar iform; 

 tubes formed by both gametangia; receptive gametangia cylindric; 

 zygospores ellipsoid, 85-1 00 ^ x 11 5-1 60 /x; median wall brown and 

 smooth. (PI. XXVII, Figs. 4-5.) 



United States: Iowa; Illinois; Indiana; Pennsylvania; New Jersey; 

 Massachusetts. 



Widely reported from European countries. 



This is certainly not the species described by Czurda (1932) which has 

 6 to 10 chroma tophores. The earliest figures published agree with those of 

 Petit (1880) in having 4 chromatophores. In any event, the description 

 given here characterizes a species that is very common in the east central 

 states and agrees with Borge's interpretation in the first edition of the 

 SiisswasserfJora, 9. In the Handbuch der Pflanzenanatomie (Bd. VI, 2 Teil., 

 p. 65) Czurda (1937) figures this species with 4 chromatophores. 



83. Spirogyra elliptica Jao 1935. Smensia. 6, p. 596, PI. 6, Fig. 72. 



Vegetative cells 115-128^^ x 128-568 /a, with plane end walls; 4 to 6 

 chromatophores, making i to 3 turns in the cell; conjugation scalar- 

 iform; tubes formed by both gametangia; fertile cells cylindric and 

 shortened; zygospores ellipsoid with pointed ends, 82-106 /a x 144-202 /x; 

 median wall smooth, yellow-brown. (PI. XXVII, Fig. 6.) 



China, Szechwan, January, 1933. 



84. Spirogyra wollnyi de Toni 1889. Sylloge Algarum. 2, p. 754. 



Wollny. Hedwigia. 1887, p. 166 (as S. elegans). 



Vegetative cells 90-100^^ x 270-350 /a, with plane end walls; 6 to 8 

 chromatophores, making 2 to 2.5 turns in the cell; conjugation scalar- 

 iform; tubes formed by both gametangia; fertile cells cylindric; zygo- 

 spores elhpsoid, 90-100/U, X 140-190/A; median wall yellow-brown, 

 smooth, with distinct suture. 



CJcrmany, Dresden; South Africa, Queenstown Cape, July, 1930 

 (Stephens Coll.). 



