26 P. T. CLEVE, ON DIATOMS FROM THE AKCTIC SEA, 



large nodule in the middle. Striae coarse, composed of 2 — 3 

 puncta. F. V. linear, narrow, angularly bent; connecting 

 merabrane with several rows of finer puncta. 



Length 0,06 m.m. Breadth 0,oo7. Heigth 0,oi3. 



Striae on the convex valve 11 in 0,o2 5 m.m. on tbe con- 

 cave valve 14 in 0,025 m.m.; puncta on the connecting mem- 

 brane 17 in 0,0 2 5 m.m. 



Spetsbergen Brandwyns Bay, Greenland, Finmarken. 



Pl. IV, fig. 23 a F. v. 6 & ^ S. v. 



131. Rhoiconeis Bolleana Grun (Verh. 1863, pag. 147, 

 Pl. XIII, fig. 11 a and h) common in the arctic seas Spets- 

 bergen Brandwyns Bay, Danes Id., x\msterdam Id. Greenlajid 

 very common. 



Striae on the convex valve 18 in 0,02 5 m.m. on the con- 

 cave valve 22 in 0,0 2 5. Length 0,0 2 5 — 0,ii'. Height 0,0 24 

 — 0,02 2 m.m. 



Grunow discovered this species on algae from the nor- 

 thern Pacific ocean. 



132. Rhoicosphenia curvata (Kg) Heiberg {Gomphon. cur- 

 vata & marina Sm Syn. I, Pl. XXIX, fig. 245 — 246). Spets- 

 bergen, Greenland, Finmarken. 



133. Amphipleura rigida Kg {A. sigmoidea Sm. Syn. I, pag. 

 45, Pl. XV, fig. 128). Spetsbergen Kings Bay (160 faths) 

 Greenland. 



134. Tryblionella marginata Sm (Syn. I, pag. 35, Pl. X, 

 fig. 76 a & 76 h). Spetsbergen Hackluyts. 



? 135. Tryblionella punctata Sm (Syn. I, pag. 63, Pl. X, 

 fig. 76 a & Pl. XXX, fig. 261) Spetsbergen Kings Bay. 



136. Nitzschia sigma Kg (Syn. I, pag. 39, Pl. XIII, fig. 

 108) Greenland. Spetsbergen Kings Bay (160 faths). Finmarken. 

 This species occurs in the Atlantic and according to Grunow, 

 in the Mediterranean sea. Red sea. Cape of Good Hope, 

 Tahiti, Honduras and Nicobaren Ids. 



? 137. Nitzschia distans Gregory (Diat. of Clyde, pag. 

 530, Pl. XIV, fig. 103) Spetsbergen Kings Bay (160 faths). 



