106 



MR. W. WEST ON THE FRESHWATER 



Table {continued). 



Genera. 



Oocystis 



Porphyridium 

 Pleurococcus 



Acanthococcus 

 Chlorococcum 



Glceocystis 



Eremospha?ra 

 Botryoeoccus.. 



Urococcus 



Rhaphidium 



Scenedesm us 



Polyedrium 



Nostoe 



Cylindro3permum 



Anabaena 



Calothrix 



Rivularia 



Tolypothrix .., 

 Petalonerna . . , 

 Scytonema ... 

 Stigonema 



Oscillaria 



Microcoleus ... 



Lyngbya 



Spirulina 



Chroococcus ... 



Glceocapsa , 



Synechococcus 



Merisraopedia 

 Tetrapedia , 



Aphanocapsa 



Glaucocystis .., 



Microcystis .. 

 Aphanothece .. 



Ccelosphyerium 



Cyclotella 



Melosira 



Surirella 



Cyraatopleura 

 Epithemia — 

 Eunotia 



Ceratoneis 



Cymbella 



Cocconeraa ... 



Encyonema . . . 



Amphora 



Cocconeis 



Acbnanthidium 

 Achnanthes ... 

 Odontidium ... 



Fragilaria 



Diatoma 



No. of 

 species. 



3 



1 



2 



2 

 2 



4 



1 

 2 



1 



1 

 6 

 5 



1 

 1 

 2 



1 

 3 



2 



1 

 2 



2 



7 

 1 



1 

 2 



2 



3 



1 

 4 



1 



1 

 1 

 2 

 1 

 1 

 2 

 2 



7 

 2 



7 



11 



1 



4 

 4 



2 

 1 

 3 

 2 

 2 

 3 

 1 

 2 



No. of 

 subspecies. 



No. of 



varieties. 



No. of 



forms. 



1 



1 



4 



1 



1 



1 



