I. 



The Freshwater Algae of the Canadian Arctic Expedition, 



1913-18 



By Chables W. Lowe 

 Lecturer on Botany, The University of Manitoba, Winnipeg 



The Freshwater Algae of the Canadian Arctic expedition were collected by- 

 Mr. Frits Johansen, the marine biologist who accompanied the Southern Party. 

 The collections were obtained in Alaska, from the arctic regions of the North- 

 west Territories as far east as Bernard harbour, and from islands near the arctic 

 coast.- The algae were collected from as many different situations as possible 

 — exposed rocks, warm streams, still and running water, lakes and tundra ponds. 



In such latitudes as those in which these samples of waterlife were obtained, 

 it is almost impossible to make an examination at the time of collection to 

 determine which collections are likely to be of special interest and worth obtain- 

 ing in considerable quantity, and which are going to turn out poorly. In con- 

 sequence the collections varied greatly; some bottles containing but little 

 material were rich in both species and numbers, while a few which seemed to 

 be better filled were found to contain only sand particles and unrecognizable 

 decaying organic matter. 



The richest collection was secured from an Hippuris swamp at Herschel 

 island, Y.T. (Plate II., fig. 2). This is a small island situated a short distance 

 from the mainland in the Beaufort sea, and about halfway between the inter- 

 national boundary at Demarcation point and the mouth of ths Mackenzie 

 river. The swamp, which is about half a mile from the sea, at an elevation of 

 approximately 200 feet, is a widened portion of one of the many creeks inter- 

 secting the island. The fact that the island is much visited by waterbirds 

 may account to a large extent for the variety of algal species found there. 



The low temperature in these northern latitudes makes it necessary to 

 preserve all collections in alcohol almost immediately after they have been 

 gathered. Alcohol, as is well known, is by no means a good fixing agent for 

 algae and, as a consequence, the algae in the collections, for the most part, were 

 poorly fixed. The protoplasmic contents of the cells were found to be much 

 contracted and the walls of many of the desmids collapsed. Some of the 

 desmids had even lost their original shapes, owing to the fact that portions 

 of their walls had become inverted. In many of the Myxophyceae the alcohol 

 had altered the colour of the sheath and of the contents. 



The Examination of Material from Brackish Ponds. 



The examination of material from brackish waters was of special interest, 

 revealing a green algal flora almost entirely freshwater in character. In samples 

 collected from a brackish pond at Teller, Alaska, there were not only many 

 species of algae but each species was represented by numerous individual plants. 

 I therefore inquired of Mr. Johansen as to the pond's salinity, its nearness to 

 the ocean, and as to its supplies of fresh water from melting snow. Mr. Johansen 

 kindly furnished me with the following information. 



There were two kinds of brackish ponds examined by the expedition: 

 (1) very shallow lagoon ponds, from a few inches up to one foot in depth, in 

 actual connection with the sea, at least at high tide, and (2) brackish ponds 

 containing water all the year round, situated farther inland than the lagoons 



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