l66 SAUNDERS [4 2 ] 



Very abundant in freshwater pond near Seldovia, Cook Inlet (424). 

 Diameter 8-12/1, length 100/1. 



Tetmemorus brebissonii (Menegh.) Ralfs. 



In freshwater near Prince William Sound : frequent. 

 Diameter 23/1, length 78 /i. 



Tetmemorus laevis ( Kuetz.) Ralfs. 



In a freshwater stream, Virgin Bay (300) ; Yakutat Bay. 



Diameter 21-24/1, l en gth 91-100/1. The plant is slightly constricted 

 and not at all punctate. 

 Pleurotaenium nodosum (Bail.) Lund. 



Common in a freshwater pond, Popof Island. 



Diameter 40-45/1, length 290-325/1. 



Pleurotaenium truncatum (Breb.) Naeg. 



In a freshwater pond near Seldovia, Cook Inlet. 

 Diameter 45 //, length 216 /t. 



Disphlnctium cucurbita (Breb.) Reinsch. 



In a freshwater pond near Prince William Sound (302). 

 Diameter 27 /i, length 67/1. 



Disphinctium connatum (Breb.) DeBary. (Plate XLIII, fig. 30.) 



In a freshwater pond near Seldovia, Cook Inlet. Only one speci- 

 men was seen. 



Diameter 24/1, length 38/1. 



Docidium baculum Breb. 



In a freshwater pond, Popof Island. 



Diameter 27/1, length 228/1. The plant is slightly wider than the 

 description given, but is not at all narrowed as are the other species. 



Docidium coronulatum Grun. 



In a freshwater pool near Kukak Bay. 

 Diameter 40/1, length 432/1. 



Docidium dilatatum (Cleve.) Lund. 



In a freshwater pond, Popof Island. 



Diameter 13/1, length 165/1. The plant has five pearly granules 

 at each end. 



Docidium gracile Wittr. 



Triploceras gracile BAIL. Micr. 



Common in fresh water near Prince William Sound. 

 Diameter 27/1. The plant has two rows of rather long spines. 



