212 



E. Jergensen. 



var. Gregorii (Balks.) Gri .\. 



Grun. in Cl. and Gruk. Arct. Diat. p. 37. Navicula Gregorii Ralfs in Prttch 



Inf. p. 001. A. Schm. Nords. Diat. pi. II, f. 22. 



Very rare: Stamsund r, Gaukvsero r. 



Distribution: Coasts of the North Sea. Baltic. Arctic regi- 

 ons. Pacific ( >cean. Kerguelen. 



N. northiimbricn Dokk. 

 Donk. Micr. Jouvn. I, p. 9, pi. I. f. 5. A. Scum. Atlas pi. 47, figs. 19—20. 



Very rare: Stamsund r, Stene rr. 

 Distribution : North Sea. 



N. zostereti Grun. (?) 

 Gkuk. in Wien. Verh. 1860 p. 528, pi. IV, f. 213. A. Scum. Atlas pi. 47, f.43. 



Rare: Stamsund r. Stene r, Gaukvsero r. 

 Distribution: The Mediterranean. Indian Ocean. 

 Ocean. Brazil. 



Pacific 



N. fortis (Greg.) Dons. 



Donk. Brit. Diat. p. 57, pi. 8, f. 8. Pinnnlaria /'. Greg, ilicr. Journ. IV, 



p. 47. pi. V. f. 19. A. Schm. Atlas pi. 46, figs. 37—39. 



Perhaps only a coarse variety of N. cancellata. 

 Very rare: Stene, r. 



Distribution: North Sea. Arctic regions (Spitsbergen, Pinmark, 

 Greenland). 



N. rostellata (Greg.) A. Schm. 



A. Scum. Novds. Diat., expl. ad pi. II („N. rostellaria GREG. ") Pinnularia r. 



Greg. Diat. of Clyde p. 488, pi. IX. E. 20. 



Very rare: Stene, r. Probably the same species as the follow- 

 ing one. There does, however, really exist a form answering to 

 Gregorys figure, without a central transverse area. 



Distribution: Coasts of the North Sea. 



N. crucifera Grun. 

 A St hm. Atlas pi. 41). figs. 50—53; Nords. Diat. pi. II, f. 31 („rostellaria Gri g ') 



Must be reckoned as a variety to the preceding species (or vice 

 versa). 



Very rare: Stamsund r; Gaukva-ro r. 



Distribution: Coasts of the North Sea. Baltic. The Medi- 

 terranean. Sumatra. 



N. distans (W. Sm.) Cl. ' 

 Cl. 1. c. p. 35. Pinnularia d. W. Sm. Brit. Diat. I, p." 56, pi. 18, f. 169. 



Very rare: Raftsund r. Stene r. 

 Distribution: North Sea. Arctic regions. 



N. compressicaiida A. Schm. 

 A. Scum. Nords. Diat. p. 91, pi. II. f. :>-">; Atlas pi. 46. f. 62. 



The peculiar aspect of the ends of the valve is due to the 

 convexity. The valve is boatshaped with sharp stems, at the bot- 

 tom of which the terminal nodules are situated. Thus they are 

 rather distant from the very ends. 



Rare : Stamsund r -(-. 



Distribution: Coasts of the North Sea. Morocco. The Me- 

 diterranean. 



N. siiperimposita A. Schm. 

 A. Schm. Nords. Diat. p. 90, pi. II, f. 34; Atlas pi. 46. f. 61. 



In many respects answering to the preceding species, though 

 undoubtedly distinct. 



Very rare: Stamsund. r. Several specimens observed. 

 Distribution: West coast of Norway. Baltic. Morocco. China. 



N. opima Grin. 



.V. fortis var.? opima Grun. Novara p. DO, pi. I A, f. 13. V. opima A. Scum. 



Atlas pi. 46. figs. 24—26. 



Very rare: Stamsund. r. 



Distribution: West coast of Norway. Baltic. Arctic regions. 

 Barcelona. 



d. Ltevistriata? Cl. 1. c. p. 66. 



Radiate stria', not distinctly punctate nor lineolate. Valve 

 more or less lanceolate. 



N. palpebralis Breb. 

 Breb. in \\. Sm. Brit. Diat. I, p. 50, pi. 31. f. 273. Van Heckck Synops. 



p. 96, pi. 11. f. 9. 



Rare: Stamsund r+, Moskenstrommen r, GaukvaTo r. 

 Distribution: Coasts of the North Sea. The Mediteranean. 

 East coast of North America. Davis' Strait. Galapagos Islands. 



var. Barclavana (Greg.) VH. 

 VH. Synops. p. 97, pi. 11. £. 12. Navicula B. Greg. Diat. of Clyde p. 480. 



pi. IX, f. 9. 



Rare: Stamsund. r. 



Distribution: Coasts of the North Sea. The Mediterranean. 



var. semiplena (Greg.) Cl. 

 (i. p ,.. p , to. Hnnulatia s. Greg. Micr. Journ. VII. p. s4. pi. VI. 1'. 12. 



Rare: Stamsund. r. 



Distribution: Scotland. Finmark. Spitsbergen. 



var. angulosa (Greg.) VH. 

 Van Herrck Synops. pi. 11. f. 10. Navicula a. Greg. Micr. Journ. I v. p. 42, 



pi. V, f. 8. a. Schmidt Nords. Diat. pi. IT, f. 19. 



Rather frequent: Stamsund +, Stene r, Gaukva?ro r+. 

 Distribution: Coasts of the North Sea and Western Europe. 

 The Mediterranean. 



var. minor Grun. 



Grun. in Cl. et Ghun. Arct. Diat. p. 30, pi. I, f. 23. Navicula in. Greg. 



Diat. .'I' Clyde p. 477, pi. IX. 1". 1. 



Rare: Stamsund r. CaukvaTo r. 

 Distribution: Finmark. Belgium. 



N. pra?secta A. Si w 

 A. Schm. Nords. Diat. pi. II. f. 20. 



Recalls the var. semxplena of the preceding species (cf. Cl. 

 1. c. p. 70), but has a much finer structure. Stria? 15 on 10 |)-. 

 An obscure line is to be seen between the central area and the 

 margin. Perhaps a species of Caloneis. 



