360 



Conjugate 



(79) and afterwards by Klebs ('85), Schroder ('02) and others. In various 

 species of Glosterium one end of the cell becomes temporarily fixed and the 

 whole cell then performs swinging movements with the fixed end as a pivot. 



Fig. 224. Various filamentous types of Desmids. A, Desmidium occidentale W. & G. S. West. 



B, D. coarctatirm var. cambricum W. West. C and D, Gymnozyga moniliformis Ehrenb. ; 



C, single cell ; D, dividing cell. E G, Phymatodocie Nordstedtiana Wolle. H, Phy. irregular is 

 Scbmidle. I, Spondylosium eUipticum W. & G. S. West. J L, Sphasrozosma excavatum 

 Ralfs ; K and L, zygospores. M, Spondylosium secedens De Bary. N, Sphserozosma granu- 

 latiim Roy & Biss. var. trigranulatum W. & G. S. West. O, Spondylosium rectangulare 

 (Wolle) W. & G. S. West, a, front view; b, vertical or end view; c, side view; d, basal view 

 of seniicell. A and B, x 333 ; C O, x 433. 



Sooner or later the other pole becomes similarly attached and further 

 oscillatory movements are carried out. Sometimes, as Stahl showed in 

 Cl. moniUferum, the cell swings completely over through 180 and then 



