KONGL. SV. VET. AKADEMIENS HANDLINGAR. HAND 26. N:0 2. 129 



4. N. Haradaae Pant. (1893). — V. broadly elliptical, with broad, rounded ends. L. 0,025 ; 

 B. 0,0 18 mm. Axial area indistinct. Central area large, somewhat transverse, half as broad as 

 the valve. Strite 20 in 0,01 mm. i^adiate throughout. — Pant. III Pl. VI f. 100. 



Habitat? »Sentenai» (Pant.). 



5. N. (lepressa Cl. (1891). — V. elliptical, with rosträts ends. L. 0,022; B. 0,oo9 mm. 

 Surface of the valve depressed between the margin and the longitudinal and transverse area. 

 Central area about '/j of the breadth of the valve. Striee 27 in 0, 01 mm., more distant (about 24 

 in 0,01 mm.) in the middle, slightly radiate, especially near the ends. — Cl. D. of Finl. p. 35 

 Pl. II f. 4. 



Fresh water: Sweden, Areskutan in Jämtland! Wernamo, fossil! Finland (Imandrian Lap- 

 land, Suomenniemi, fossil)! 



6. N. binodis Ehb. (1840). — V. strongly constricted in the middle, with rostrate-capitate 

 ends. L. 0,02.i; B. O.oos mm. Axial area indistinct. Central area small. Strice about 30 in 0, 01 

 mm., sligthly radiate. — Ehb. Ber. 1840 p. 18. W. Sm. B. D. I p. 53 Pl. XVII f. 159. Grun. 

 Verh. 1860 p. 551 Pl. II f. 42. Donk. B. D. p. 38 Pl. VI f. 3. V. H. Syn. p, 108, Suppl. Pl. B. f. 33. 



Fresh water: England (Sm.), Belgium (V. H.), Switzerland! Japan! 



7. N. (Dickieia) iilvacea Berkl. (1844). — V. linear-elliptical, with rounded ends. L. 0,o2 5 

 to 0,035; B. 0,008 to 0,012 mm. Axial area indistinct. Central area a narrow, transverse fascia 

 furcate at the margin. StriiS. 16 in 0,oi mm., slightly radiate at the ends. Frustules in leaf-like, 

 flat and stipitate gelatinous mäss, in length about 1 to 5 cm. — Dickieia ulv. Berkl. in Kiitz. 

 Bae. p. 119. V. H. Syn. Pl. XVI f. 10. 



Marine: Scotland (Dickie), Ireland (0'Meara), Balearic Islands! 



8. N. asymraetrlca Pant. (1893). — V. narrow elliptical, obtuse. L. 0,025; B. 0,oi mm. 

 Central area a broad fascia, reaching the margins, where is, unilaterally, in the middle of the area 

 a single stria. Striae radiate, 19 in 0,oi mm. — Pant. III Pl. VII f. 110. 



Habitat? »Sentenai» (Pant.). 



9. N. mntica Kutz (1844). — V. of variable shape, elliptic-lanceolate, frequently with un- 

 dulated margins. L. 0, 013 to 0,033; B. 0, 007 to 0, 01 i mm. Axial area narrow. Central area 

 large, transversely dilated, with an isolated punctum on one side of the central nodule. Strise 18 

 to 20 in 0,01 mm. radiate at the ends, distinctly punctate. A few of the median strite shorter 

 than the rest. — Kutz Bac. p. 93 Pl. III f. 32 (according to Arnott). Grun. A. D. p. 40. 



Forma Cohnii Hilse (1860). — V. elliptic-lanceolate, with rounded ends. — Stattron. Cohnii 

 HiLSE Beitr. p. 83. N. mutica v. Coh. V. H. Syn. p. 95 Pl. X f. 17. Stauron. i^olymorpha Lägst. 

 Spitsb. D. p. 39 Pl. I f. 12. 



Brackish water: Spitsbergen! Belgium (V. H.), Bengal! Daintree River, Australia! Löst 

 Spring Ranch, Calif. ! 



Forma Göppertiana Bleisch (1861). — V. lanceolate. — Sfauroneis Semen Ehb. M. G. XXXVIII 

 A 20 f. 1 (1854)? Stauron. Göppertianu Bleisch Rabh. A. E. N:o 1183 (1861). Nav. mutica 

 Grun. Verh. 1860 p. 538 Pl. V f. 16. Stauron. Cohnii Schum. Tatra p. 78 Pl. IV f. 61. N. mitt. 

 v. Göppertiana V. H. Syn. p. 95 Pl. X f. 18, 19. 



Fresh or brackish water: Belgium (V. H.), Nova Scotia! West Indies! Ecuador! 



Forma producta Grun. (1880). — V. lanceolate, with broad, truncate ends. — Grun. A. D. p. 41. 



Forma vmfricosa Kutz (1844). — V. inflated, with capitate ends. L. 0,oig to 0,022; B. 0,06 

 to 0,08 mm. Strice 17 in 0,oi mm. — Stauron. ventric. Kutz Bac. p. 105 Pl. XXX f. 27. Greg. 

 M. J. IV Pl. I f. 10 (1856). Nav. (St.) rent. V. H. Syn. p. 96 Pl. IV f. 1 b. 



Brackish water: Argentina! 



K. Sv. Vet, Akad. Hund. Band 26. N:o 2. 17 



