38 A Canadian Arctic Expedition,. 1913-1918 



Eunotia diodon Ehr. 



This likewise was found only at Teller, and ini ©>niy ©me- saample fimm the 

 lagoon lake, July 27, 1913. Rare. 



Eunotia monodon Ehr. 



This was a little more plentiful than E. diodom,. taing,- fioMindl ncpesn; two 

 occasions in July, 1913, in the same lake. 



Eunotia triodon Ehr. 



This was the most frequent of the genus, being fbundl in aaraniples; oMaincd 

 in July and August, 1913, at Teller, and on June 28,. 19^1®, aft Maartiim pxamft. 



Eunotia pectinalis (Kiitz.) Rab. 



This species was found in a small quantity in a tumdira pomdl ait TeHer, 

 August, 1913. 



Eunotia praerupta Ehr. 



The lagoon lake at Teller was again the only locality in; whielii tMs-. species 

 was found, July, 1913. It was not uncommon. 



Eunotia praerupta Ehr. var. curta Grun. 



Amongst the specimens of the last mentioned species; were' & few of this 

 variety. 



Epithemia Breb. 

 Epithemia Argus Kiitz. 



This species occurred in a sample obtained June 17, I9I@, in a moss-tundra 

 lake at Chantry island. Only a few frustules were observed. 



Epithemia gibba Kiitz. 



This was a fairly common species and was found in various localities. It 

 occurred in the lagoon lake and brackish pond at Teller, in the river bed, and 

 embedded in the calcareous pebbles taken from the bed of the warm creek in 

 northern Alaska, November, 1913, and from the big lake at the creek mouth 

 at Bernard harbour. 



Epithemia Hyndmanii W. Sm. 



This diatom was found only in the lime-encrusted pebbles taken from the 

 warm creek near the Sadlerochit river. It was fairly abundant. 



Epithemia Sorex Kiitz. 



This species was not quite so frequent as the last named. It likewise was 

 found in fresh and brackish water at Teller. It also occurred in the plankton 

 from the lake at Bernard harbour and at the creek mouth. 



Epithemia turgida (Ehr.) Kiitz. 



This was the most abundant species of the genus. It occurred in fresh and 

 brackish samples at Teller, in various samples from Bernard harbour, and was 

 the commonest diatom associated with the calcareous pebbles taken from the 

 warm creek in northern Alaska. 



Epithemia turgida (Ehr.) Kiitz. var. granulata Kiitz. 



Amongst the specimens found in the calcareous pebbles found in the warm 

 creek, northern Alaska, were a large number of valves characteristic of this 

 variety. They were obtained only from these pebbles. 



