213 PRELIMINARY CATALOGUE OF PLANTS. 



Pandorina, Bory. 



P. Morum, Bory. Not rare. 

 Hydrodictyon, Roth. 



H. utriculiitum, Roth. Sluggish waters. 



Pediastrum, Mey. 

 P. tetras, Ehrh. 

 P. Boryanurn, Menegh. 

 P. pertusum, Kg. Numerous varieties. 

 P. Ehrenbergii, A. Br. 

 All of these forms occur frequently in the smaller ponds. 



Coelastrum, Naeg. 



C. sphaericum, Naeg. Ponds. 

 C. microporum, Naeg. Ponds. 

 C. Naegelii, Raben'u. Ponds. 



Sorastrum, Kg. 



S. spinulosum, Kg. Ponds. 



Scenedesmus, Mey. 



S. obtusus, Mey. Shallow, stagnant water. 



S. acutus, Mey. Shallow, stagnant water. 



S. caudatus, Corda. Shallow, stagnant water. 



Ophiocytium, Naeg. 



O. cochleare, A. Br. Ponds. 

 Characium, A. Br. 



C. subsessilis, Wolle. Cranberry pond. 



Protococcus, Ag. Forms of this genus, as far as they have come 

 under my notice, are mere conditions of spores, no true plants — 

 hence omitted. 



Polyedrium, Naeg. 

 P. trigonum, Naeg. 

 P. aculeatum, Wolle. Not rare in ponds. 



Dictyosphaerium, Naeg. 



D. Ehrenbergianum, Naeg. 

 D. reniforme, Bulnh. 



Tetraspora, Ag. 



T. lubrica, Ag. Sluggish streams. 

 T. gelatinosa, Desv. 



