KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 27. N:0 3. 29 



Var.? suhimpressa Grun. (188U). — V. lanceolate. L. 0,o65; B. 0,oi6 mm. Strise 11 to 12 

 in 0,0 1 mm., crossed by a longitudinal line. — N. subimpr. Grun. A. D. p. 39 Pl. II f. 45. 



Marine: Sea of Kära (Grun.). 



Var.? tenuis Cl. (1883). — V. elliptic-lanceolate, with a longitudinal impression on both 

 sides of the median line. L. 0,o.s8; B. 0,ui5 mm. Strite 18 in 0,0 1 mm., unilaterally interrupted 

 by a narrow transverse fascia. — N. suhimpressa var. tenuior Cl. Vega D. p. 470 Pl XXXVII f. 49. 



Marine: Cape DeschnefF! 



58. N. irregularis Pant. (1889). — V. narrow, lanceolate, with subacute ends. L. 0, 126; 

 B. 0,021 mm. Axial area broad on one side of the median line, narrow on the other. Strise 7 

 to 10 in 0,01 mm. almost parallel, alternately longer and shorter, on one side of the median line 

 crossed by a linear lateral area. — Pant. II p. 49 Pl. XXX f. 424. 



Marine: Hungary, fossil (Pant.). 



I have not seen this species, but to judge from the figure it seems to be akin to iV. trunsi- 

 tans var. asymmetrica . Somewhat similar is N. primoråialis Pant. (III Pl. XXV f. 382). 



59. N. (Rhoiconeis) sibirica Grun. (1882). — V. lanceolate, subacute. L. 0,o4 to 0,o6; 

 B. 0,01 mm. Axial area indistinct; central area large, subquadrate. Strise 10 (at the ends 10 to 

 11) in 0,01 mm. almost parallel throughout, distinctly lineate. Frustules arcuate, with narrow 

 connecting zone. — Bhoiconeis Bolleana var.? sibirica Grun. in Cl. M. D. N:o 302. Cl. Vega 

 p. 469 Pl. XXXVn f. 38. 



Marine: Cape Wankarema! 



Var. asymmetrica Cl. 1883. — Axial area unilateral, narrow. Striffi 11 in 0, 01 mm. — 

 N. Bolleana v. asijm. Cl. Vega p. 469 Pl. XXXVII f. 39. 



Var. »lediterranea Cl. — V. narrow, rhombic-lanceolate acute. L. 0, 1 ; B. 0,oi3 mm. Central 

 area rounded. Strite 7 in 0,oi mm., distinctly lineate; lineolfe about 27 in 0,oi mm. 



Marine: Gulf of Naples! 



N. sibirica resembles N. Bolleana, but differ.s by its more parallel strite. and by the narrow 

 connecting zone. The A". Zostereti A. S. N. S. D. III f. 3 seems to belong to N. sibirica. 



60. N. (Bhoiconeis) superba Cl. (1883). — V. rhomboidal with subacute ends. L. 0,o6; 

 B. 0,02 mm. Axial area unilateral, more or less narrow. Central area small, somewhat trans- 

 verse. Strife 8 to 10 in 0, 01 mm., parallel, finely lineate, frequently crossed, on one side of the 

 median line by an irregular, narrow lateral area. — Vega p. 468 Pl. XXXVI f. 23. 



Marine: Cape Wankarema! 



Var. elliptica Cl. (1883). — V. elliptical. L. 0,065; B. 0,02 mm. Strise 10 in 0,oi mm. 

 Marine: Cape Wankarema! 



The valves of this species seem to be somewhat dissimilar, the concave having möre distant 

 striye, frequently crossed unilaterally by a narrow area. 



61. N. (Rhoiconeis) obtusa Cl. (1882). — V. linear with broad, rounded ends. L. 0,055 to 

 0,075; B. 0,014 to 0,018 mm. Axial area narrow, unilateral, irregular. Central area small. Strite 

 11 in 0,01 mm., slightly radiate in the middle, and convergent at the ends, frequently crossed 

 by irregular longitudinal, narrow bands. — Cl. a. M. D. N:o 315 to 318. Cl. Vega p. 469 

 Pl. XXXVI f. 25. 



Marine: Cape Wankarema! 



62. N. ammophila Grun. (1882). — V. linear-lanceolate, subacute. L. 0,oi7 to 0,03; B. U,oo5 

 mm. Axial and central areas indistinct. Strise 10 to 11 in 0, 01 mm., finely lineate, in the 

 middle subradiate, at the ends transverse (12 to 13 in 0, 01 mm.). — F. D. Öst. Ung. p. 149 

 Pl. XXX f. 66 to 69. 



Marine and brackish: Coasts of England and Sweden (Grun.), Hungary, Tallya, fossil (Grun.). 



