Diatoms. 



I'll 



2V. humerosa Breb. 

 Breb. in W. Sm. Brit. Diat. II, p. 93. Van Heurck Synops. p. 98, pi. XI. f. 20. 



Very rare: Raftsund r. 



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

 gions. The Mediterranean. Black Sea. Caspian Sea. The Red 

 Sea; Indian Ocean. Sidney. Cameroon. 



N. momlifera Cl. 



Cl. 1. c. p. 43. N. granulnta Breb. in Dunk. Micr. Joum. VI, p. 17. pi. III. 

 f. 19, nun X. granulata Hail. 



Very rare: The ©stnesfiord r. 



var. heterosticha Cl. 



Cl. 1. c. V. granulata A. Scum. Atlas, pi. 6, figs. 15 — 16. 



Very rare: Raftsund. r. 



Distribution (of the main species): North Sea. Ceylon. 

 Madagascar. The var. only known from Hungary, fossil. 



A", la tissim a Greg . 

 Greg. Micr. Jouvn. IV, p. 40, pi. V, figs. 4. 4 . A. Schm. Nords. Diat. pi. I, f. 30. 



Frequent: Moskenstremmen r +, Svolvser r, the Ostnestiord r, 

 Raftsund r, Stene r -f-. 



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

 diterranean. Black Sea. Indian Ocean. Pacific Ocean. 



N. punetulata \Y. Sm. 



var. kefovingensis (Ehkb.) Cl. 



Cl. 1. ,-. p. 18. Pinnularia /,. Ehrb. Berl. Ak. L840, p. 20. Navicida k. 



A. Schm. Atlas pi. 47. figs. 61—62. 



Very rare: Svolvaer. 141 i>- long. 

 Distribution: Brackish water: Scotland. 



N. digito-radiata (Greg i A Schm 

 A. Schm. Nords. Diat. p. 92, pi. III. f. 4. Pinnularia it. GREG.jMicr. Joum. 



IV. pi. I. f. 32. 



Frequent: Stamsund -f-, Svolvser r, the 0stnesfiord r, Stene r. 

 Distribution: Coasts of the North Sea. Arctic regions. Cas- 

 pian Sea. New York. 



.V. directa w. Sm. 



\V. Sm. lirit. Diat. I, p. 56, pi. is. r. 172. A. Schm. A.tlas pi. 17. figs. 4—5 

 I rnr. genuina Cl. 1. c. p. 27). 



Rare: Stamsund r-f. the 0stnesfiord r, Stene r. 

 Distribution: Coasts of the North Sea. Arctic regions. Yokohama. 



var. remota Grcn. 



Grcn. iu Cl. et (ins. Arct. Diat. p. 39. A. Schm. Nords. Diat. pi. Ill, f. 2. 



Somewhat rare: Stamsund -f. the Ostnestiord r, Gaukvsero r. 

 Distribution: Coasts of the North Sea. Arctic regions. The 

 Mediterranean. Red Sea. Central America. 



var. subtilis (Greg.) Cl. 



W. Sm. Brit. Diat. I, p. 52, pi. 16, f. 151. Van Hecrck Synops. p. 98, pi. 11, f. 16. Cl. Vega p. 4b7. Pinnularia s. Greg. Diat. .a' Clyde, p. 188, pi. IX. I'. 19. 



Very rare : Stamsund r. 



Distribution: Coasts of the North Sea. Arctic regions. The 

 Mediterranean. Caspian Sea. America. Indian Ocean. 



N. frandulenta A. Schm. 



A. Schm. Atlas pi. 70, f. H0: Nords. Diat. pi. Ill, f. 18 2 (without name). 



Rare : Stamsund r -f . Many specimens. 

 Distribution: North Sea. Sevastopol. 



c. Lineolatee Cl I. c. II. p. 10. 

 Radiate or parallel striae, transversely lineate. 



A", radiosa Kutz. 



Kutz. Bacill. p. 91, pi. IV, f. 23. Van Heurck Synops. p. 83, pi. 7, f. 20. 

 Inol. Pinnularia acuta W. Sm. Brit. Diat. I. p. 56, pi. XVIII, f. 173. 



Rare: Stene, r. 



Distribution: Frequent fresh water species, especially in Nor- 

 thern and Western Europe. Asia, Africa, America. 



N. peregriua Ehrb. 

 Ehrb. Am. p. 133. pi. 1.!. figs. 5 — »i. A. Scum. Atlas pi. 47, figs. 57 — 60. 



Very rare: Gaukvaero, r. 



Distribution: Brackish water. Coasts of the North Sea. Bal- 

 tic. Adriatic Sea. Arctic regions. America. Pacitic Ocean. In- 

 dian Ocean. 



Rare: Stene r, Gaukvaero r. 

 Distribution: Scotland. Arctic regions. 



N. fLnuiarchica (Cl. e( Grun.) Cl. 

 Cl. 1. <•. ],. 28. Sfauroneis f. Cl. vt Grcn. Arct. Diat. p 47. pi. III. t'. 63. 



Very rare: Stene, rr. Very similar to the figure quoted, 

 though wanting the fainter or blank lateral areas. Also very 

 similar to N. transitans forum minuta Cl. Vega pi. 36, f. 37. 



N. frigida Grin. 



Grun. in Cl. et Grcn. Arct. Diat. p. 39. Grcn. Diat. Franz Jos. Land. p. 103, 



pi. I. f. 25. Navinila kariana v. frigida Cl. 1. c. p. 28. 



Probably derived from the plankton. 



Rare: Stamsund, r+. 



Distribution: Arctic regions. Cf. above p. 105. 



N. cancellata Dome. 



Dunk. Brit. Diat. p. 55. pi. 8, figs. 4 a. b. A. ScttM. Xonls. Diat. pi. II, 



rigs. 36 — 37. 



Very variable, probably also including N. zostereti ami .V. north- 

 umbrica. 



Very frequent: Moskenstrommen -)-, Stamsund +, Svolvser +, 

 the Ostnestiord +, Raftsund r, Stene + c, Gaukvtero c c. 



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

 gions. The Mediterranean. Indian Ocean. Pacific Ocean. Ker- 

 guelen. 



