KONGL. SV. VET. AKADEMIENS HANDLIN6AR. BAND 26. N:0 2. 61 



45. C. ai)normis Grun. (1878). — V. lanceolate, with broad, obtuse ends. L. 0,028 to 0,0.15; 

 B. 0,007 to 0,009 mm. Axial area very narrow; central area small, orbicular. Median lines straight, 

 with approximate central pores, and terminal fissures turned in contrary direction. Strise 30 

 (Grrunow) to 34 in 0,oi mm. transverse. Longitudinal lines faint, submarginal. — Nav. abnormis 

 Grun. in CI. M. D. N:o 142. A. D. p. 46. Gal. abn. Icon. n. Part. IV PL I f. 6, 7. 



Marine: Bohuslan, Sweden! 



46. C. brevls Grev. (1857). — V. elliptical, with rostrate, obtuse ends. L. 0,o6 to 0,o8; 

 B. 0,022 to 0,03 mm. Median line with distant central pores. Axial area narrow, dilated in the 

 middle to a large, orbicular space. Strise 14 in 0,oi mm., almost parallel, not distinctly punctate. 

 Longitudinal lines indistinct. — Nav. brevis Greg. D. of Clyde p. 478 PL IX f. 4. A. S. N. S. D. 

 PI II f. 15. DoNK. B. D. p. 19 PL III f. 4. V. E. Syn. p. 97 PL XI f. 19. — Nav. crassa Greg. 

 M. J. Ill p. 41 PL IV f. 18 (1855)? 



Marine: Spitsbergen! Greenland! Finmark! North Sea! North Siberian Sea, Cape Desch- 

 niff! Lofanger, Angermanland, Sweden, (integlacial deposit)! Sydney (Thum.)! 



Var. vexans Grun. (1880). — Elliptic-lanceolate, with broad, obtuse ends. — Nav. brevis v. 

 vexans Grun. A. D. p. 30. A. S. N. S. D. PL II f. 14. Nav. hrev. v. eUiptica V. H. Syn. p. 97, 

 PL XI f. 18. 



Marine and brackish: Sea of Kara! Finmark! Japan (strise 18 in 0,oi mm. "Weissflog. Coll.)! 



Var. distoma Grun. (1880). — V. elliptical, with broad ends. Central pores of the median 

 line distant. Central nodule large, thick. Longitudinal lines distinct, single or double. 



Forma latior: Broadly elliptical. L. 0,o78; B. 0,026 mm. Strise 13 to 14 in 0,oi mm. — 

 Nav. (brevis var.?) diatoma f. lat. Grun. A. D. p. 31 PL I f. 25. 



Brackish water: Sea of Kara (Grun.), Japan! 



Forma angustior: Narrow elliptical. L. 0,o68; B. 0,oi9 mm. Strise 15 to 16 in 0,oi mm. 

 — Nav. (brevis var.?) diatoma f. ang. Grun. A. D. p. 31 PL I f. 26. 



Brackish water: Jamal, Sea of Kara (Grun.). 



Forma bicuneata Cl. — V. with parallel margins and cuneate ends. L. 0,o85; B. 0,o29 mm. 

 Strise 14 to 15 in 0,oi mm 



Marine: Japan, fossil (Brun Coll.)! Sydney! China! 



Nav. brevis and its varieties are nearly akin to N. amphisbcena. 



47. C. Ibottnica Cl. N. Sp. — V. elliptic-lanceolate. L. 0,05; B. 0,oi8 mm. Central pores 

 distant. Axial area broad, gradually dilated towards the middle, where it expands to a transverse 

 fascia. Strise 22 in 0,oi mm. slightly radiate towards the ends. Longitudinal line faint, margi- 

 nal. — PL III f. 42. 



Slightly brackish water: Gulf of Bothnia at Pitea! 



48. C. Lagerheimil Cl. N. Sp. — V. elliptic-lanceolate convex, with obtuse ends. L. 0,042; 

 B. 0,009 mm. Axial and central areas uniting in a lanceolate-linear space. Strise 17 in 0,oi 

 mm. very slightly radiate towards the ends. Longitudinal lines indistinct marginal, or inframarginal. 



Fresh water: Ecuador, Quito (Lagerheim)! 



49. €. latiuscula Kutz (1844). — V. elliptical to lanceolate. L. 0,o75 to 0,09; B. 0,023 to 

 0,0 3 mm. Axial and central areas uniting in an irregularly lanceolate space. Strise 18 to 21 

 in 0,01 mm. parallel, finely punctate. Longitudinal lines marginal or inframarginal. — Nav. 

 latiuscula Kutz Bac. p. 93 PL V f. 40. Grun. Verb. 1860 p. 534 PL IV f. 38. Donk. B. 

 D. p. 27 PL IV f. 7. Nav. patula W. Sm. B. D. I p. 49 PL XVI f. 139 (1853). V. 11. Syn. 

 Suppl. B f. 29. 



Fresh water, larger lakes: Scotland; Sweden: Venern! Malaren! Baltic, freshwater deposits 

 of the Ancylus-epoch! Gotland! Switzerland (Lac des 4 cantons, Lac Leman)! 



