34 ZYGNEMATACEAE 



United States: Illinois; Indiana; Ohio; Massachusetts. 

 Widely reported from Europe. 



50. Zygnema normani Taft 1934. Trans. Amer. Micros. Soc. 53, 



p. 213, PI. 17, Fig. 12. 



Vegetative cells 24-28 /^ x 30-73 /x; conjugation scalariform; zygo- 

 spores in one of the gametangia; receptive gametangia greatly inflated 

 on the conjugating side; zygospores globose or subglobose, 36-46 /a x 

 35-45 /n; median spore wall yellow-brown, scrobiculate; pits 3-4 M in 

 diameter, 2.5-4 /t apart. (PL V, Fig. 6.) 



United States: Oklahoma. 



India. 



51. Zygnema insignisporum Couch 1944. Ohio Jour. Set. 44, 



p. 277. 



Vegetative cells 24-28/A x 39-71 m; conjugation scalariform; recep- 

 tive gametangia inflated on the conjugating side; zygospores globose to 

 ovoid, 32-35 /A x 32-35 /a; outer wall of 2 colorless layers, of which the 

 outermost is smooth, the inner scrobiculate, with pits 4-5 /^ in diameter 

 and about 7/A apart; median wall punctate, yellow. 



United States: Arkansas. 



52. Zygnema vaginatum Klebs 1886. Untersuch. Bot. Inst. Tu- 



bingen. 2, p. 135, PL 3, Fig. 13. Notarisia. 1, pp. 340-41. 

 1886. 



Vegetative cells 25-27^1 x 37-75/^; conjugation scalariform; zygo- 

 spores in one of the gametangia; receptive gametangia slightly en- 

 larged; zygospores globose to ovoid, diameter about 28^1; median spore 

 wall brown, verrucose-tuberculate. 



Germany; Austria. 



Czurda (1932) and Krieger (1941) described this species as having 

 scrobiculate median spore walls. No reason for the change from the 

 original description is given. 



53. Zygnema subcruciatum Transeau 1934. Trans. Amer. Micros. 



Soc. 53, p. 212. 



Vegetative cells 24-30/M x 26-60M; conjugation scalariform; zygo- 

 spores in one of the gametangia; receptive gametangia cylindric or 

 enlarged, mostly on the inner side; zygospores globose to ovoid, 25-32^ 

 X 28-40M; median spore wall brown, finely scrobiculate. (PL V, Fig. 7.) 



United States: Oklahoma; Texas; Arkansas; Louisiana; Illinois; Ohio. 



France; Norway; Sweden; China. 



