26 MINNESOTA BOTANICAL STUDIES. 



ULOTRICHIACEAE (Kg.) Borzi em. De Toni. Syll. Alg. i : 

 151. 1889. 



244. Hormiscia zonata (Web. and Mohr) Aresch. var. 



valida (Nag.) Rabenh. F1. Eur. Algar 3: 362. 

 1868. 

 On rocks wet with surf. Grand Marais, Lake Su- 

 perior, Minnesota. Coll. A. H. Elftman. July 27, 

 1896. 



PALMELLACEAE (Decne.) Nag. em. De Toni. Syll. Alg. 

 i: 559. 1889. 



245. Scenedesmus obliquus (Turp.) Kg. Syn. Diat. in Lin- 



naea. 8 : 609. 1833. 

 Grown in aquarium in which water was saturated with 

 nitrous oxide. University of Minnesota, Minneapolis, 

 Minnesota. Emil Sandsten. February 23, 1898. 



246. Chlorochytrium archerianum Hieron. in Jahres. Schles. 



Gesellsch. 296. 1887. 

 In cells of Sphagnum Which had been kept in the Uni- 

 versity plant-house six weeks. Osceola, Wisconsin. 

 Coll. Conway MacMillan. September 15, 1896. 



247. Tetraspora cylindrica (Wahlenb.) Ag. Syst. Alg. 188. 



no. 2. 1824. 

 Attached to lake bottom, abundant around the outside 

 harbor rocks. Grand Marais, Lake Superior, Minne- 

 sota. Coll. A. H. Elftman. July 27, 1896. 



248. Palmella miniata Leibl. var. aequalis Nag. Einzell. 



67. pi. 4. D. f. 2. 1849. 

 On submerged rocks and pebbles in slow current. 



Minnehaha creek. Soldiers' Home, Minneapolis, 



Minnesota. September 27, 1896. 

 This species contains calcium carbonate in quantity. It 



is accompanied by filaments which much resemble 



Stigeoclontum in its transition stage. 



ZYGNEMACEAE (Menegh.) Rabenh. F1. Eur. Algar. 2 : 228. 

 1868. 



249. MougeotiaparvulaHAss. var. angusta(HAss.) Kirchn. 



Alg. Schles. 128. 1878. 



