566 



Annul* of the South African Museum 



Pig. 34. — Zygnema stpiraie, n. sp. •>. Portion of two filaments in process of 

 conjugation, showing the development of the membrane-thickenings. 

 h. Conjugating threads, showing three zygospores, c. < Jonjugating threads, 

 without membrane-thickenings, d. Two conjugating threads, stained with 

 methyl blue, showing two zygospores and the membrane-thickenings, e. 

 Two threads in conjugation, showing the spiral twisting. /, g. Zygospores, 

 in side-view. }i Ordinary vegetative cells, i. A zygospore in side-view, 

 showing the outlines of the two conjugating cells. a, b, c, d, h, and i, 

 x 215; e, x 105;/ and g, x 530, 



