71 



Remaining Problems. 



It remains to be determined experimentally whether or not this alga 

 produces a toxin, the nature of the toxin, the action of the toxin on 

 fishes, etc. 



A much more difficult problem is to determine the exact condition 

 under which this alga will develop. If this alga reappears this problem 

 will be attacked. 



Literature Cited. 



Arthur, J. C, '83. Some algae of Minnesota supposed to be poisonous. 



Bull. Minn. Acad. Nat. Sci., Vol. 2, pp. 1-12. 

 Brun, M. J., '80, L'eau rouge du lac de Neuchatel. Archiv. d. Sci. phys. 



et nat., T. 3, p. 337. 

 Hyams, Isabel F. and Richards, Ellen H., '01. Notes on Oscillatoria 



prolifica (Grenville). I. Life History. Tech. Quart., Vol. 14. No. 



4, pp. 302-310. 



'02, II. Chemical composition. Ibid, Vol. 15, pp. 308-315. 



'04, III. Coloring matter. Ibid, Vol. 17, pp. 270-276. 

 Klausener, Carl, '08. Die Blutseen d. Hochalpen. Int. Rev. d. Hydrog. u. 



Hydrob. B.I, ss. 359-424. 

 Nelson, N. P. B., '03. Observations on some alg£e that cause "water 



bloom." Minn. Bot. Stud, 3rd. Ser., Pt. 1, pp. 51-56. 

 Olive, E. W., '05. Notes on the occurrence of Oscillatoria prolifica 



(Grenville) Gomont in the ice of Pine Lake, Waukesha County, 



Wisconsin. Wis. Acad. Sci., Art. and Letters, Vol. XV, pp. 124-134. 

 Steuer, A., '10. Planktonkunde s. 277-8. Leipzig. 



