VEGA-EXPEDITIONENS V ET EN SKAPLI G A ARBETEN. 



469 



convex valve 9 in the middle, 10 in 0,oi mm. toward the ends, 

 reaching almost to the median line ; on the concave valve 8 — 

 10, on one side of the valve not reaching the median line, 

 on the other reaching the median line, hut interrupted hy a 

 linear area. 



Length 0,06 mm. Breadth 0,02 mm. — PI. 36, fig. 23. 



Cape Wankarema. 



var. eUiptica CI. Valve elliptic. Stria) parallel, 10 in 0,oi 

 mm. Length 0,o65 mm. Breadth 0,02 mm. — PI. 36, fig. 24. — 

 Cape Wankarema. 



The concave valve of this variety is scarcely different 

 from N. incudiformis Grun. 



N. (BhoiJconeis) ohtitsa CI. N. Sp. (Rhoic. ohtusa CI. in CI. 

 & Moll. Diat. 315 — 318) Elongated, linear, with rounded obtuse 

 ends. Stria3 curved, not parallel, very faintly lineate, on one 

 half of the valve reaching the median line, on the other end- 

 ing at some distance, irregularly interrupted, 11 in 0,oi mm. 

 Length 0,0 75 mm. Breadth 0,oi4 mm. — PI. 36. fig. 25. — Cape 

 Wankarema. 



N. (Ilhoihoneis) BoJJecina Grun. (Verh. 1863, pag. 147, PI. 

 XIII, fig. 11) Greenl., Spitsb., Finm., Kara (Matotschkin), Cape 

 Wankarema. 



Specimens from Greenland have 8 radiant stride in 0,oi 

 mm. in the middle, 12 near the ends. Specimens from Wan- 

 karema are less arcuate, have in 0,oi mm. 10 stria), wdiich are 

 almost parallel. The strios are transversely finely lineate as in all 

 species of the directa-group. Mr. Grunow has named this variety 

 from Wankaremia Illi. Bolleanct var.? Slberica (CI. & Moll. Diat. 

 No 302.) — PI. 37, fig. 38. — Another variety from Cape Wanka- 

 rema has asymmetric striation and 11 stripe in 0,oi mm. var. 

 asymmetrica CI. length 0,045 mm. breadth O.oi mm. PI. 37, fig. 39. 



N. hariana Grun. (A. Diat. pag. 39, PL II, fig. 44) Kara, 

 F. J. L., Cape Wankarema. 



a- (jenuina Stria) 12 — 14 in 0,oi mm. Length 0,o85 mm. 

 Breadth 0,o2 6 mm. — Kara, F. J. L., Cape Wankarema. 



/?. deter sa Grun. Mpt. Stria) interrupted on both sides of 

 the median line by more or less broad areas. Length 0,09 

 mm. Breadth 0,o24 mm. — Kara, F. J. L., Cape Wankarema. 

 — PI. 36, fig. 36. 



T. minor Grun. (A. D. pag. 5. N. frigida Grun. A. D. pag. 

 39) Strife 16 — 18 in 0,oi mm. Length 0,044 — 0,o7 mm. Breadth 

 0,012 — 0,013 mm. — Kara, F. J. L. 



