May, 1917] The AlgcE of Michigan 231 



OEDOGONIACEyE. 



Oedogonium acrosporum DeBary. Railroad pool, New Buffalo, 



May 31. 1915; pool, Seney, Aug. 12, 1915. 

 Oedogonium borisianum Wittrock. New Buffalo, May 31, 



1915. 

 Oedogonium concatenatum Wittrock. New Buffalo, May 31, 



1915. 

 Oedogonium crenulato-costatum Wittrock. Carp Lake, Emmet 



Co., Aug. 9, 1915. 

 Oedogonium crassum Wittrock. New Buffalo, May 31, 1915; 



bog north of Blaney, Aug. 12, 1915. 

 Oedogonium crispum Wittrock. New Buffalo, May 31, 1915. 

 Oedogonium crispum var. inflatum Hirn. New Buffalo, May 



31, 1915. Variety new to America. 

 Oedogonium cryptoporum vulgare Wittrock. New Buffalo, 



May 31, 1915. 

 Oedogonium cyathigerum Wittrock. Saugetuck, June 1, 1915. 

 Oedogonium fragile Wittrock. New Buffalo, May 31, 1915. 

 Oedogonium gracillimum Wittr. & Lund. New Buffalo, May 



31, 1915. 

 Oedogonium braunii Ktitz. Railroad pool, Seney, Schoolcraft 



Co., Aug. 12, 1915. 

 Oedogonium grande Kiitz. New Buffalo, May 31, 1915; 



Saugetuck, June 1, 1915. 

 Oedogonium grande var. angustum Hirn. Ditch, Breedsville, 



June 4, 1915. 

 Oedogonium irregulare Wittrock. Saugetuck, June 1, 1915. 

 Oedogonium laeve Wittrock. Saugetuck, June 1, 1915. 

 Oedogonium paludosum var. parvisporum Hirn. New Buffalo, 



May 31, 1915. 

 Oedogonium pratense Transeau. Railroad ditch, Mackinaw 



City, Aug. 9, 1915. 

 Oedogonium rufescens Wittrock. New Buffalo, May 31, 1915; 



Saugetuck, June 1, 1915. 

 Oedogonium rugulosum Nordstedt. New Buffalo, May 31, 



1915. 

 Oedogonium americanum sp. nov. Dioecious, macrandrous; 



oogonia single, globose to depressed-globose, pore superior; 



oospore globose, ellipsoid-globose, or depressed-globose, 



filling the oogonium or only partly filling it, spore wall 



