FRESHWATER ALGM 265 



Compared with the Alga-flora of Arctic land-areas in a similar latitude, that of 

 the Antarctic continent is distinctly poor. The Green Algse are relatively fewer, and 

 there is a lack of diversity among the species of diatoms. Both of these facts may 

 be directly due to the undoubted salinity of most of the lakes near the coast. Such 

 a condition would be prejudicial to the growth of most Green Algse, and the majority 

 of freshwater species of diatoms would be excluded for the same reason. The most 

 truly freshwater of the diatoms observed were_jthpse from the ponds on the lower 

 slopes of Mt. Erebus. The comparative poorness of the Antarctic Alga-flora may 

 also -be in part due to the greater severity of the climate combined with the remoteness 

 of the Antarctic continent from other continental areas. 



BRIEF ACCOUNT OF THE COLLECTIONS 



Most of the collections were made by Mr. James Murray in the near vicinity of 

 the winter quarters of the Expedition at Cape Royds on Ross Island. One was made 

 by the leader of the Expedition at Hut Point, Ross Island, and two others on the 

 mainland of South Victoria Land. The following data will include brief statements 

 as to the habitats and the principal Algse found in each collection. 



I. Ross ISLAND 



The camp at Cape Royds was at 77 32' S. lat. and 166 12' E. long. All the 

 collections were made within a few miles of this, except the one at Hut Point, lat. 

 77 50' S. The numerous ponds and lakes near the camp yielded quite a number of 

 interesting Algse, and special attention should be drawn to the numerous Blue- green 

 Algse, some of which occurred in extensive sheet- like expansions. 



1 Pony Lake, Cape Royds 



April 22, 1908, and January 4, 1909; coll. J. Murray. Close to winter quarters. 

 Never clear of ice except in small parts between November 28, 1908, and the end of 

 January 1909. Temperature of water never much above freezing-point, the highest 

 record being 35 F. on December 4, 1908. 



In January the material was distinctly green, and consisted of quantities of 

 Chlamydomonas subcaudata and C. intermedia forma antarctica among the numerous 

 trichomes of Phormidium autumnale. 



In April the material (obtained from under the ice) was darker in colour and 

 contained fewer Algse. 



In both months filaments of the curiously contorted Phormidium antarcticum 

 were common, also Pleurococcus frigidus. 



2 Ponds, Cape Royds 



A number of small ponds in which the temperature about the end of December rose 

 to 60 F. Coll. J. Murray. 



