HOW TO KNOW THE FRESH-WATER ALGAE 



57b Colony composed of round or oval cells, gelatinous sheath not 

 stratified 58 



58a Semicircular fragments of old mother-cells partly inclosing daugh- 

 ter cells or lying scattered about in the mucilage. Fig. 48 



SCHIZOCHLAMYS 



Fig. 48. Schizochlamys geia- 

 tinosa A. Braun. 



At times the free-floating 

 gelatinous masses of this 

 plant may be of macroscopic 

 size and they may be 

 scooped from the surface of 

 the water by hand. More 

 Figure 48 frequently the growths are 



less extensive and small aggregates of cells occur intermingled with 

 other algae in shallow water situations. The fragments of old mother- 

 cell walls help to identify this plant, and under favorable optical con- 

 ditions the tuft of fine, gelatinous pseudocilia may be seen. 



58b Fragments of old mother-cell walls not apparent 59 



59a Colonies sac-like or irregularly globose; cells arranged in 4's. See 

 Fig. 35b TETRASPORA 



59b Colonies shaped otherwise; cells not arranged in 4's 60 



60a Cells ovoid, compactly arranged in semi-opaque mucilage which 

 is often brown or yellow and obscures the cells; colonies frequent- 

 ly compounded by interconnecting strands of tough mucilage be- 

 tween clusters of cells. Fig. 49 BOTRYOCOCCUS 



Fig. 49. Botryococcus Biaunii Kuetz., 

 showing an expression in which a 

 colonial complex is formed by inter- 

 connecting strands of tough mucil- 

 age. Colonies frequently appear 

 solitary and as a yellowish-brown 

 lump in which individual cells can 

 scarcely be seen, if at all. The 

 color of the colony lies mostly in 

 the mucilage. This species often 

 forms "blooms" especially in hard 

 water lakes. 



Figure 49 



45 



