6. Freshwater Algae from Juan Fernandez and 



Easter Island. 



By 

 K. MUNSTER STROM. 



With i textfigure. 



The material, upon which the present contribution to the flora of Juan 

 Fernandez and Easter Island is based, was collected by Professor Dr. C. SKOTTS- 

 BERG during the Swedish Expedition to the Pacific 1916 — 1917. 



Numerous samples were collected; partially they were preserved in bottles, 

 partially they were dried up. 



On the whole, I have examined 28 samples preserved in chemicals and 

 about 25 dried ones. Only very few came from Easter Island. The collection 

 was very kindly submitted for my inspection by Prof. SKOTTSBERG and for- 

 warded to Christiania. 



Very little is previously known concerning the freshwater flora of these is- 

 lands, but unfortunately the present collections were so poor that only twenty- 

 five species were observed, among them only two Desmids. 



I therefore very much regret being unable to give any account of the 

 geographical relationship of the freshwater microflora to that of other coun- 

 tries. A thorough examination of the Freshwater Algae of these Islands would 

 no doubt be of interest, as it may help to supply the phyto- and zoogeographical 

 results, made out from the examination of the higher plants and of the fauna. 



Probably, the extreme poverty of the samples is partly due to the fact 

 that they were collected by a non-specialist, but there are reasons to believe 

 that the Islands are not very rich in Freshwater Algae. This may be due to 

 many causes (there does not exist a single lake or pond in Juan Fernandez); 

 perhaps the lonely position of the islands is of some significance. 



I am, however, inclined to believe that at least a greater number of sub- 

 aerial Algae may be found by future explorers as the climate of the higher 

 parts of Juan Fernandez is very damp. 



The majority of the Algae are wholly ubiquitous species, even the two 

 Desmids are widely distributed forms. I have, however, mentioned the area of 



