Preface 



The Great Lakes region lies in a highly glaciated part of North 

 America and therefore possesses a terrain which provides many 

 hundreds of lakes, swamps, and marshes. Thus the area is highly 

 suitable for an abundant algal flora, especially because of variation 

 in water chemistry — a variation which is related primarily to the 

 geological history and nature of the underlying rock in the different 

 sections. Hence the list of algal species in the Great Lakes region 

 is a long one. Approximately 1300 algae (exclusive of desmids and 

 diatoms) have been reported from Wisconsin and Michigan, the 

 latter region being represented principally in the papers of Ackley, 

 Gustafson, Taft, and Transeau. To date, no major treatment of Mich- 

 igan algae has appeared, but in 1920 and 1924 Gilbert M. Smith 

 published the results of his extensive phytoplankton surveys of Wis- 

 consin lakes. Probably for no other area of comparable size any- 

 where in the world has so much systematic field work been done, or 

 so detailed and informative a presentation of algal distribution been 

 issued. Smith's volumes, which are based upon collections made 

 during the period 1913 to 1917, represent a survey of some 230 lakes, 

 mostly in the northern counties of the state. 



As indicated by Smith in his preface (1920, p. 2), he found it 

 necessary to defer an originally planned study of filamentous and 

 attached algae because of the magnitude of the survey, emphasis 

 consequently being directed toward the plankton. It is well known, 

 of course, that organisms which make up the phytoplankton rep- 

 resent a wide range of algal groups, inasmuch as almost all classes 

 of algae have at least some free-floating or swimming members. 

 Within the same genus there may be both drifting and normally 

 attached species, whereas other, closely related, genera may contain 

 only species which are sedentary, at least in the vegetative state. In 

 the present study, special attention has been given the attached and 

 tychoplanktonic forms, particularly the strictly aquatic filamentous 

 algae. In order to make as complete a record as possible for this 

 region, it has been considered advisable to describe here the species 

 previously reported, as well as those new to the regional list. Species 

 not collected by the author are included if they appear to be authen- 

 tically reported or if the printed record is substantiated by preserved 



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