Zygnemopsis desinidioides (West & West) Transeau in 

 Transeau, Tiffany, Taft, & Li 1934, p. 215 



PI. 69, Fig. 8 



Filaments short, slender, and fragile, much constricted at the 

 cross walls, composed of cylindrical cells, broadly rounded at the 

 apices, 8-1 l/n in diameter, 25-40;li long. Zygospores rectangular in 

 front view, broadly ellipsoid in side view; the median wall finely 

 and densely punctate; 14-24ja in diameter, 20-27- ( 30 ) ju, in long 

 dimension. Gametangia persisting about the spore as 4 horn-like 

 processes filled with pectic compounds. 



Rare; in shallow water of swamps; lake margins. Mich., Wis. 



Zygnemopsis minuta Randhawa 1937, p. 312 



Vegetative cells 8-10;a in diameter, 36-46|U, long; chloroplasts 2 

 irregular cushion-like bodies. Reproduction mostly by lenticular 

 aplanospores. Zygospores quadrate in a 4-lobed sporangium (some- 

 times 3-lobed), formed by remains of gametangia; median spore 

 wall brown and smooth; 22— 24/a in diameter. Conjugation usually 

 between dissociated cells. 



Mich. 



Zygnemopsis spiralis ( Fritsch ) Transeau in Transeau, 

 Tiffany ,Taft, & Li 1934, p. 214 



PI. 69, Fig. 7 



Filaments long, composed of short cylindrical cells, 17-22/a in 

 diameter and up to 130/x long; chloroplasts 2 stellate bodies. Zygo- 

 spores quadrate in outline, formed in the enlarged connecting tube 

 but extending into the gametangial cells which form horn-like 

 enlargements; outer spore wall brown and densely punctate; 30-36/a 

 in diameter, 48-54/1, in long dimension. 



Mich., Wis. 



Zygnemopsis Tiffaniami Transeau 1944, p. 244 

 PI. 74, Fig. 4 



Vegetative cells 10-12/x in diameter, 30-60jii long; chloroplasts 

 with 2 pyrenoids. Zygospore quadrate, the margins either retuse or 

 straight to angles which may be produced or retuse (concave); 

 median spore wall smooth; 20-24/a in diameter, 28-32/1, long. Con- 

 jugation frequently between dissociated cells. 



Mich. 



[ 328 1 



