40 A Canadian Arctic Expedition, 1913-18 



SUBIEELLEAE. 



' ' Cymatopleura W. Sm. 



Cymatopleura Solea (Br6b.) W. Sm. 



This diatom was not common, being seen only on two occasions. One 

 frustule occurred in the content of a fish stomach, October 4, 1915, and two more 

 from' the Hippuris swamp at Herschel island, August, 1914. 



Surirella Turpin. 

 Surirella arctissitna A.S. 



This species was found only in a mud sample taken from the bottom of the 

 big lake at Bernard harbour, February, 1916. 



Surirella fastuosa Ehr. 



This is a marine form found at Teller. 



Surirella ovalis Br 6b. 



This species occurred in the lagoon lake at Teller and at Bernard harbour 

 in the big lake, September, 1915, and in a fish stomach taken in October of the 

 same year. 



Surirella recedens A.S. 



This species, sometimes regarded as a variety of S. fastuosa, was found 

 only at Teller. 



Surirella regina Janisc. 



This also was found only at Teller, along with S. fastuosa and S. recedens. 

 Not common. 



Ctmbelleae. 



Amphora Ehr. 

 Amphora ovalis Kiitz. 



This species was fairly abundant in the lagoon lake at Teller. It was 

 exceedingly common at Bernard harbom-, appearing in plankton and other 

 collections from the big lake in June, July, August, September and November, 

 1915, and February, 1916, also at the creek mouth in July, in a fish stomach, 

 October, 1915, and in the brackish pond, August, 1915. It also occurred at 

 Herschel island, August, 1914. 



Cymbella Ag. 

 Cymbella cistula Hempr. 



This species was found only in the lagoon lake at Teller, August, 1913. 



Cymbella cuspidata Kutz. 



This species, like the last named, was found only in the lake at Teller, 

 July, 1913. Some of the species varied and were approaching the form of 

 Cymbella heteropleura (Ehr.) Ktitz. 



Cymbella gastroides Kiitz. 



This species was almost as frequent as Amphora ovalis Kiitz. and was found 

 in the same localities; at Teller, in the lagoon lake and brackish pond, July and 

 August, 1913; Herschel island, August, 1914; the creek mouth and big lake at 

 Bernard harbour, August, 1915, and February, 1916, in both bottom samples 

 and plankton. It was also found in the Ophrydium mass, August, 1915. 



