14 v. T. CLEVE, ON DIATOMS FROM THE AllCTIC SEA. 



common in the Arctic sea. S-petshergen: ex. gr. Kings Bay, 

 Treureuberg Bay. Gi-eenland. Finmarken Grötsund. 



C. Thuretii is found to be tolerably common on the coasts 

 of the Xorth Sea and according to Grunow it occurs sparingly 

 in the mediterrauean sea and near Honduras. Among all the 

 numerous samples from various tropical seas, examined by 

 me, I nowhere met with C. Thuretii, but in mud from 

 Magellhaens Strait I found it very common. 



49. Cocconeis decipiens Cl N. Sp. Broadly oval, median 

 line elegantly sigmoid, nodule transversely elongated. Striai 

 faint, but distinctly granular 24 in 0,0 2 5 m.m. Length 0,04 7 6 

 — 0,0595 m.m. Breadth 0,o;<4 — 0,042 m.m. Greenland very rare. 



Similar to C. heteroidea Hantzch but the strias are much 

 more distant and composed of distinct granules. Pl. I, fig. 6. 



50. Cocconeis arctica Cl. X. Sp. Broadly oval Avith roun- 

 ded apices; median line sigmoid; central nodule obsolete, 

 surrounded by a large blank space. Stri» distinct, and radiate, 

 composed of somewhat elongated puncta, so arranged that 

 they form irrcgular, wavy longitudinal lines. 



Length 0,0 4i m.m. Breadth 0,04 2 5 m.m. Strise 33 — 34 

 in 0,02 5 m.m. Greenland. Finmarken Grötsund. P. Il, fig. 

 11 « & k 



51. Cocconeis pellucida Grun (Novara. p. 12 Hantzch in 

 Piab. Beitr. pag. 21, fig. 11). Very common. Finmarken. 

 Greenland. Spetshergen: Amsterdam Id., Brandwyns Bay. 



52. Cocconeis Scutellum Ehb. Spetsbergen: Amsterdam Id., 

 Kings Bay. Greenland. Var. distans (Greg) Grun (Novara 

 pag. 12) Greenland. 



Cocc. Scutellum occurs abundantly in most seas, also in 

 the Baltic. 



53. Cocconeis glacialis Cl X. Sp. Oval with broadly 

 rounded extremities; median line straight. Central nodule 

 surrounded by a large blank space. Stria3 radiate, very distinct, 

 composed of sperate and somewhat elongated puncta, more 

 numerous near the margin. The puncta are disposed in lon- 

 gitudinal, wsivj and irrcgular lines; some of them, being 

 larger than others, give the valve in a certain focus the 

 appearance of being covered with scattered puncta (almost 



