iv Minnesota Algae 



believed that the plan of writing out in full the author's name and the 

 title of his article will prove a great saving in time for the one who uses 

 the book. In the case of amateurs it will also serve to give in a short 

 time an intimate knowledge of the names of algologists and an idea of the 

 work already done in the group. 



The descriptions in general follow those of Gomont, Bornet, Thuret 

 and Flahault. Constant reference has of course been made to Forti's re- 

 cent volume. Wherever possible the original descriptions have been con- 

 sulted. Possibly a mistake has been made in not repeating the synonym 

 after each title. Instead each synonym has been inserted but once, follow- 

 ing the first article in which it occurs. The principal aim of the book, 

 however, is to encourage original investigation in the field among the 

 plants themselves. For a full list of synonyms, reference must be made 

 to De Toni's "Myxophyceae." 



I wish to tender my best thanks to Dr. Frederic E. Clements for advice 

 and much kind assistance during the preparation" and publication of this 

 volume which was undertaken at his request. To Miss Charlotte Waugh 

 I am much indebted for her painstaking work upon the pen and ink draw- 

 ing of the figures. 



The author hopes that several persons in each state or section of the 

 country may decide to undertake a systematic and careful investigation 

 of the blue-green algae in their neighborhoods, and would be very glad 

 to enter into a correspondence with such workers. 



JOSEPHINE E. TILDEN. 



Kimberly Road, Epsom, 



Auckland, New Zealand, 

 December 21, 1909. 



