Tilden: fresh-water algate in Minnesota. 599 



220. Closterinm acerosum (Schrank) Ehrenb. Abh. Berl. 



Akad. 1831. 

 Sleepy Eye lake. May 17, 1895. Coll. A. A. Butler. 



221. Cosmarium laeve Rabenh. PI. Eur. Algar. :5:161. 1868 < 



Sleepy Eye lake. May 17, 1895. Coll. A. A. Butler. 



222. Plectonema wollei Farlow. In Bull. Bussey Inst. 77. 



1875. 

 Long lake, Hennepin county. September 5, 1895. 

 Coll. B. T. Shaver and,/. E. T. 



223. Phormidium i'avosuin (Bory) Gomont. Ann. Sci. Nat. 



Bot. 16:180. 1892. 

 In trough, Osceola, Wis. August 30, 1895. 

 In tub, Long Lake, Hennepin county. September 5, 

 1895. Coll. B. T. Shaver and J. E. T. 



224. Phormidium incrustatum (Naeg.) Gomont. Bull. Soc. 



Bot. de France. 36:Cliv. 1889. 

 Osceola, Wis. August 28, 1895. 



225. Phormidium ainbiguum Gomont. Ann. Sci. Nat. Bot. 



1<>: 178. 1892. 

 Slate fish hatcheries, St. Paul. September 15, 1895. 



226. Aphanizomenon flos aquae Kales. Ann. Mag. Nat, Hist. 



5:340. 1850. 

 Lake of the Woods. July 20, 1891. Coll. Conway 

 MacMillan. 



Lake Minnetonka. 1895. Coll. A. L. Crocker. 

 Long lake, Hennepin county. September 5, 1895. 

 Coll. B. T. Shaver and J. E. T. 



227. Chamaesiphon incrustans Grun. In Rabenhorst's PL 



Eur. Algar. 2:149. 1865. 

 In tank in botanical laboratory, Minneapolis. Febru- 

 ary 15, 1896. 



228. Dichothrix orsiniana (Kg.) Bornet and Flahault. 



Am. Sci. Nat. Bot. VII. 3:376. 1886. 

 Kenwood, Minneapolis. August 3, 1895. 



229. Clathrocystis aeruginosa Henfr. Micr. Journ. 53. 1856. 



Long lake, Hennepin county. September 5, 1895. 



Coll. B. T. Shaver and J. E. T. 

 Como park, St. Paul. August 10, 1895. 



