KONGL. SV. VET. AKADEMIENS IIANDLINGAR. BAND 27. N:() 3. -31 



(J5. N. inflexa (tREG. (18.50). — V. narrow, elliptic-lanceolate, with obtuse, conical ends. 

 L. 0,{)<is to 0,04.^); B. OjOOTf) to 0,008:) mm. Axial area indistincit, central area small, rounded. Strife 

 11 in 0,0 1 mm. stnmgly radiate throughout, distinctly lineate; lineohc 2ii in 0,oi mm. — Finn, 

 inflexa (tREG. T. M. S. "iV p. 48 PI. V f. 20. N. inflexa DoNK. W. I), p. 54 PI. VIII f. 2. A. S. 

 Atl. XL VI f. (ii), 70. 



Marine: Sea of Kara! North Sea! 



N. inflexa r. Biharensis Pant. II p. 48 PI. Ill f. ;5() from Biemia seems to be another 

 spe(des, as it has scarcely any resemblance to N. inflexa. 



6(i. N. iiortluimbrica Donk. (1801). — V. very convex, narrow lanceolate, with acute ends. 

 L. 0,04)) to 0,07 «; B. 0,008 to 0,oi mm. Axial area indistinct; central area small, rounded. Strite 

 10 to 11 in 0,0 1 mm. (the median stronger and more distant) very slightly radiate in the middle 

 transverse at the ends, lineate; lineolae 25 in 0,oi mm. Frustule quadrate. — Donk. M. J. I p. 9 

 PI. I f. 5. B. D. p. 54 PI. VIII f. 1. A. S. XLVIT f. 19. 20. 



Marine: North Sea! 



This species is remarkable for the extreme convexity of its valves, from which cause it is 

 very difficult to find a specimen in the valvular view. 



07. N. (Khoiconeis) Cubitus Temp. a. Brun (1889). — V. very convex, linear-lanceolate 

 with acute, excavate ends. L. 0,o9 to 0,o9.5; B. 0,oi;i mm. Axial area indi.stinct. Central area 

 a narrow, transverse fascia, arising from the two distant median strise. Terminal areas large, 

 triangular spaces (visible only in the zonal view). Stri* in 0,oi mm., parallel, coarsely lineate; 

 lineolae 21 in 0,oi mm. Frustule arcuate. — D. foss. du Japon p. 42 PI. V f. 8. 



Marine: Japan, fossil! 



08. N. Zostereti (tRUN. (1800). — V. .slightly convex, narrow lanceolate, subacute. L. 0,0 6 5 

 to 0,14; B. 0,0 11 to 0,022 mm. Axial area indistinct; central area very small, orbicular. Strige 

 7 in 0.0 1 mm. (a little more close towards the ends) transverse, and .slightly curved, lineate; lineolse 

 23 in 0,0 1 mm. — Verb. 1800 p. 528 PI. IV f. 23. A. S. Atl. XLVII f. 42, 43, 44. 



Marine: Adriatic (Grun.), Bab el Man deb! Ceylon! Labuan! Java! China! Japan (Atl.), 

 Sandwich Islands (Atl.), Brazil (Atl.), Atlantic City, fossil! 



Var. seychellensis Cl. — L. 0,06 5; B. 0,oii mm. Striib 12 in 0,oi mm. 



Marine: Seychelles (Van Heurck Coll.)! 



N. Zostereti is very similar to N. direcfa, but has more convex valves and .slightly radiate, 

 striae curved towards the ends, finely lineate. 



09. N. spuria Cl. N. Sp. — V. rarrow, lanceolate, acute. L. 0,o9 to 0, i.--); B. O.oia to 0, 021 

 mm. Axial area indistinct. Central area small, irregularly roi;nded. Strise 7 in 0, 01 mm., .slightly 

 radiate in the middle, transverse at the ends, coarsely lineate; lineola' 21 to 24 in 0,oi mm. 



Marine: Mediterranean Sea (Gulf of Naples)! Adriatic! New Caledonia (Kinker Coll.)! Gala- 

 pagos Islands (Weissflog Coll.)! 



Var. asyinmetrica Cl. — Axial area naiTow, unilateral. Strise on the side opposite to the 

 axial area, cro.ssed by an irregular, narrow lateral area. L. 0,i5; B. 0,022 mm. Strise in 0,oi 

 mm., lineolse 27 in 0,oi mm. 



Marine: Hungary, fossil (Karnaud Deposit in Deby Coll.)! 



N. spuria resembles N. dirceta, from which it differs by its slightly radiate strise, and 

 N. 2)("»nata, from which it diifers by its small central area. From N. Zostereti it may be distin- 

 guished b}' its coarsely lineate strife and from N. distans by its indistinct axial area. 



70. N. fortis Greg. (1850). — V. very convex, elliptic- to rhombic-lanceolate, obtuse. L. 0,o.5 

 to 0,089; B. 0,01 to 0,0 17 mm. Axial area indi.stinct; central area small, orbicular. Strise 8 to 9 

 in 0,01 ram. slightly radiate in the middle, transverse at the ends, coarsely lineate; lineolse 24 in 



