222 The Ohio Journal of Science [Vol. XVII, No. 7, 



Pleurotaenium ehrenbergii (Breb.) DeBary. Bog pool, Seney, 



Aug. 12, 1915; Twin Lake, June 2, 1915. 

 Pleurotaenium ehrenbergii var. elongatum West. Pond near 



Orchard Lake, Aug. 15, 1915. 

 Pleurotaenium trabecula. Bog north of Blaney, Schoolcraft 



Co., Aug. 12, 1915. 

 Pleurotaenium trabecula (Ehrenb.) Nag. var. rectum (Delp.) 



W. & G. S. West. Twin Lake, June 2, 1915. 

 Euastrum gemmatum Breb. Twin Lake, June 2, 1915. 

 Euastrum ansatum Ralfs. Twin Lake, June 2, 1915. 

 Euastrum bidentatum Nag. Seney, Aug. 12, 1915. 

 Euastrum denticulatum (Kirchn.) Gay. Twin Lake, June 2, 



1915; bog near Carp Lake, Aug. 9, 1915. 

 Euastrum pinnatum Ralfs. Bog east of Caffey, Aug. 13, 1915. 

 Euastrum didelta (Turp.) Ralfs. Bog near Carp Lake, Emmet 



Co., Aug. 9, 1915. 

 Euastrum crassum (Breb.) Kiitz. Bog near Carp Lake, Aug. 9, 



1915; bog near Tw4n Lake, June 2, 1915. 

 Euastrum verrucosum Ehrenb. Railroad ditch. New Buffalo, 



May 31, 1915. 

 Euastrum verrucosum var. planctonicum W. & G. S. West. 



Railroad ditch, New Buffalo, May 31, 1915. 

 Micrasterias oscitans Ralfs. Twin Lake, June 2, 1915; Trout 



Lake, Aug. 10, 1915. 

 Micrasterias oscitans var. mucronata (Dixon) Wille. Bog near 



Carp Lake, Aug. 9, 1915. 

 Micrasterias radiata Hass. Twin Lake, Muskegon Co., June 2, 



1915. 

 Micrasterias rotata (Grev.) Ralfs. Bog near Caffey, Mackinaw 



Co., Aug. 13, 1915; bog pond near Mackinaw City, 



Cheboygan Co., Aug. 9, 1915; bog north of Blaney, Aug. 12, 



1915. 

 Micrasterias crux-melitensis (Ehrenb.) Hass. Bog pond near 



Mackinaw City, Aug. 9, 1915. 

 Micrasterias pinnatifida (Kiitz) Ralfs. Twin Lake, June 2, 



1915. 

 Micrasterias papillifera Breb. Twin Lake, June 2, 1915. 

 Micrasterias papillifera var. glabra Nordst. Twin Lake, June 2, 



1915. 

 Micrasterias apiculata (Ehrenb.) Menegh. Twin Lake, June 2, 



1915. 



