28 ZYGNEMATACEAE 



spores are formed in the tubes; zygospores globose, 30-40 /x in diameter, 

 all walls smooth and light blue in color. (PI. Ill, Figs. 13-14.) 



India, Punjab, February, 1931. 



These spores may not be mature and the color may be due to refraction 

 of light rather than the presence of a blue pigment. 



24. Zygnema synadelphum Skuja 1926. Acta Horti Bot. Univ. 



Latviensis. 1, p. no, PI. i, Fig. 2. 



Vegetative cells ly-iiiJ. x 34-120 ai; conjugation scalariform; zygo- 

 spores formed in the conjugating tubes, ovoid to spheroid, 27-36 m x 

 34-44 At; median spore wall blue, of 3 layers, of which the outer is irreg- 

 ularly punctate; pits about 1-2 ft in diameter; suture sometimes prom- 

 inent, usually not. Aplanospores cyHndric-ovoid, filling the vegetative 

 cells, otherwise similar to the zygospores. (PI. IV, Figs. 1-2.) 



United States: Oklahoma; Texas; Michigan; Ohio; Louisiana; Florida. 

 Latvia; China; Africa, Burma. 



In a collection from Alexandria, Louisiana, aplanospores were very 

 abundant. In a collection from Florida most of the spores were in the tubes, 

 but occasional spores were in the gametangia of both conjugating filaments. 



25. Zygnema terrestre Randhawa 1938. Proc. hidian Acad. Sci. 



8, p. 147, Fig. 29. 



Vegetative cells 18-24^1 x 36-60^1; conjugation scalariform, zygo- 

 spores in the tubes or extending into the gametangia, subglobose to 

 ovoid, 28-38 /A x 36-54 /x; median wall blue when mature, brownish when 

 immature, punctate with pits .5-1 /x in diameter 3-5 m apart; aplan- 

 ospores ovoid to dolioform, formed in the enlarged middle part of the 

 cells; the outer wall of the cell adjoining the spore changes to pectic 

 compound forming a collar. When mature the aplanospore walls are 

 similar to those of the zygospores. Aplanospores are 30-34 m x 36-65/1. 

 Some filaments have several of the lowermost cells with disintegrating 

 chromatophores beneath the soil surface. (PI. VII, Figs. 16-18.) 



India, Fyzabad, forming a light green felt on the soil surface of fallow 

 fields at the close of the rainy season, late September and October, 1937. 



26. Zygnema coeruleum Czurda 1932. Siisswasserfiora Mittel- 



europa. 9, p. 107, Fig. 107. 



Vegetative cells 24-26/1 x 40-55/1 in diameter; conjugation scalar- 

 iform; zygospores formed in the conjugating tubes, ovoid to globose, 

 32/1 x 32-35/1; median spore wall blue, thick, scrobiculate; pits 1.5/1 in 

 diameter, 2 diameters apart. (PI. IV, Figs. 3-4.) 



Bohemia; South Africa; northern India. 



