DICKIE, ARCTIC ALG^. 519 



From N. lat. 73°40', W. long. 57°, July 1851, among rotten 

 ice.* 



Denticula obtusa, Kg. ? Pleurosigma fasciola, Sm. 



Melosira arctica, n. s. P. angulatum, Sm. 



Navicula oxyphyllum, Kg. 



In Hinkson's Bay, N. lat. 73° 50', W. long. 57°, July 2, 1850. 



Amphora hyalina. Melosira arctica. 



Amphipsora alata, Kg. Navicula oxyphyllum. 



Ceratoneis closterium, Ehr. Nitzchia, n. sp. ? 



Cocconeis rhombus. Pleurosigma fasciola. 



Denticula obtusa. P. Thuringicum. 



Dictyocha gracilis, Kg. Schizonema, n. sp. 



Grammonema Jurgensii. Triceratium striolatum. 



In lat. 75° 42', May 1850. 



Cocconeis rhombus ? Odontella aurita. 



Navicula diclyma. Rhabdonema minutum ? 



N. semen, Ehr. Stauroneis aspera. 



N. n. sp. ? Synedra curvula. 



Nitzchia, n. sp. S. pulchella. 



Odontella obtusa. Triceratium striolatum. 



' The colouring matter of Arctic ice is due sometimes to Algce 

 decomposed and triturated by ice. The littoral species are few, kept 

 down by the abrasion of ice. The olive and yq^l AlgcB are rare. 

 Of the five olive Algce, four are British, and one (Agarum) is 

 exclusively American. Of the three red Algce, one {Polysiphonia) 

 is common in Britain, the Dumontia is American, and the third 

 is new. Of the green Algce there are six marine, and fourteen 

 from fresh water or moist places ; and about a third are British. 

 Of the three Desmids in this collection two are British, and the 

 Arthodesmus has been found in France and Germany. The 

 Diatoms are relatively numerous. 



LXXVI. — On Alg^ collected in Cumberland Sound, by 

 Mr. James Taylor, with remarks on the Arctic 

 Species in general. By G. Dickie, M.D., F.L.S. 



[With Permission, from the Proceed. Lin. Soc. Botany, vol. ix., 

 pp. 235-243. 1866. Read 15 June, 1865. (Somewhat 

 abridged.)] 



[This article should have been inserted in § I. under " West Greenland," &c. ; 

 but its close connexion with the preceding article, by the same Author, 

 and its general conclusions, allow of its insertion in this place.] 



Cumberland Sound, an arm of Davis Strait, on the west side, 

 commences about lat. 66^ 10' N., long. 64° 40' W., and is about 



* The so called " rotten " condition of the ice is described by Brown as 

 being due to the intermixture of Diatomaceous slime. See above, pp. 314- 

 315.— Editor. 



