FRESHWATER ALGÆ FROM TUDDAL IN TELEMARK. 187 



Family Palmellaceæ. 

 Genus Sphærocystis. Chodat 1897. 



270. Sphærocystis Schroeteri. Chod. 

 Frequent in the plankton. 



Genus Coccomyxa. Schinidle 1901. 



271. Coccomyxa dispar. Schmidle. 

 Rare. 



Genus GloeocysUs. Näg. 1849. 



272. GloeocysUs vesiculosa. Näg. 



This doubtful species (a stage of Ghlamydomonas?) occurred 

 in quantity in a single sample. 



Genus Asterococcus. Scherffel 1908. 



273. Asterococcus superbus. Scherff. 

 Not uncommon. 



Family Botryococcaceæ. 

 Genus Botryococcus. Kütz. 1849. 

 274. Botryococcus Braunii. Ktitz. 

 Scarce in the plankton. 



Family Protococcaceæ. 

 Genus Chlorella. Beijerink 1890. 



275. Chlorella vulgaris. Beijer. 



Associated with Chroococcus pallidus in sample 20. 

 Size: diam. cell. 6,5 u. 



Genus Trochiscia. Kütz. 1845. 



276. Trochiscia sp. 



Undeterminated species of Trochiscia occurred in many 

 samples. 



