13. Siirirelleæ. 

 C'anip.ylotlisrn^ Ehrb. 



C. decorus Bheb. 

 C. decorus Bréb. Diat, Cherb. p. 13, f. 2. Van Heueck Synops, pl. 75, f. 3. 



Not unfrequent : Moskenstrømmen r, Stamsund r, Østnestiord r, 

 Gaukværø r. 



Distribution (including- the nearly related C. Ealfiii W. Sm.): 

 Frequent on the coasts of Europe. Greenland. Java. Pacific 

 Ocean. 



W. S.M. Brit. Diat. 



C. Ralfsii W. Sm. 



30, pi. .30, f. 2.57. A. ScHM. Atla."! pi. 14, figs. 2—3. 



Diifers from the preceding species in having a linear (not 

 lanceolate) pseudoraphe. Smaller in size. 

 Very rare: Stene r, Stamsund r. 



C. annularis Greg. 

 Greg. Di.it. of Clyde p. .502, pi. XI, f. 53. A. Schmidt Atlas pi. 18, f. 7. 



Frequent: Raftsund r, Bre ttesnes— Skroven r, Gstnesflord c, 

 Stene r. 



Distribiifioti: Scotland. Tiie Skagerak. Arctic regions. 



C. Thuretii Bréb. 

 Bréb. Diat. CUerb. pl, 1, f. 3. Van Heurck Synops, p. 190, pl. 77, f. 1. 



Frequent : Moskenstrømmen r, Stamsund -(-, Svolvær r +, 

 Raftsund r, Bre ttesnes— Skroven r, Gstnesflord -\-c, Gaukværø -t-c, 

 Stene r -\-. 



Disfrihiition: Frequent on the coasts of Europe. Arctic re- 

 gions. Indian Ocean. 



C. parvnlus W. Sm. 



W. Sm. ill Biit. Diat. I, p. 30, pl. (i, f. 5«. Van Heurck Synops, p. 191, 

 pl. 77, f. 2. 



Is by some authors considered to be a form of (A Tliurrfii 

 Uricb. (cf. De Toni Syll. p. 622) by others to belong to C. decorus 

 P.RÉB. (cf. Van Heueck Traité p. 376). 



Very rare: Stene r. 



Dish-ihution: England. Belgium. 



C. eximius Greg. 

 Greg. Diat. of Clyde p. 503, pi. XI, l'. 54. 



Very rare: Stene rr. Only a broken valve. 

 Distribution: Coasts of Western Europe. Tiie Mediterranean. 

 Red Sea. Indian Ocean. 



Siirirolhi Tt up. 



S. gemma Eiirb. 



Khrb. Abli. Bhi-I. Akad. 1840, p. 76, pi. IV, f. 5. Van Hel'RCK Synojis. p. 187, 



pi. 74, figs. 1—3. 



Very rare : Gaukværø r i-. 



Distrilmtion : Frequent on the coasts of Europe. Spitsbergen. 



S. ovalis Bréb. 



KiiTZ. Bacill. p. 61, pi. 30, f. 64. Van Hel-rck Synops, p. 188, pi. 73, f. 3. 



In fresh and brackish Avater. 

 Very rare: Gaukværø r. 



car. onda (Kutz.) V. H. 



VH. Synops, p. 188, pi. 73, figs. 6—7. Sunvdla ovata KCtz. 1. e. p. 62, pi. 7, 



figs. 1-4. 



Very rai'e: Gaukværø r. 

 Distribution: Common .species. 



S. fastuosa Ehrb. 

 Ehrb. Abh. Bevl. Ak. IS4I, p. 19. Van Heurck Synops, p. 188, pi. 73. f. 18. 



Rather frequent: Svolvæi- +, Raftsund r, Gaukværø r, 

 Stene r -f. 



var. lata (W. Sm ) VH 



Van Heurck Synops, ii, lUS, pl. 72, f. 17. SwireUa }. W. Sm. Brit. Diat. I, 



p. 31, p', 9, f. 61. 



Frequent: Moskenstrømmen r -(-, Stamsund r, Svolvær r, 

 Raftsund r, Brettesnes— Skroven r. Gstnesflord r, Gaukværø r, 

 Stene r. 



Distribution: Frequent on the coa.st.s of Europe. Gulf of 

 Mexico. 



14. Achnantheæ Cl. 

 Aoliiiantli(')4 BoRY. 



A. longipes Ag. 



Ag. Syst. p. 1. Van Heurck Synops, p. 129, pi. 26, figs. 13—16. 



Very rare: Svolvær r. 



Distribution: Frequent (on algæ) on the coasts of Europe. 

 The Canary Isles. 



A. brevipes Ag. 



Ag. 1. c. Van Heurck Synops, p. 129, pi. 26, figs, 10—12. 



Rare: Stamsund r, Stene r, Østnesfiord r. 

 Distribution: Frequent on the coasts of Europe. 



Kiirorc-oiK'iiii CI. 



Valves ecostate, without marginal loculifei'ous liin. Both val- 

 ves •with narrow axial area, rather similar in structure. 



E. pseiidoiuarginata (Greg.) ('l. 



Cl. Synops. Navic. Diat. II, p. 178. Coccnnns p. Greg. Diat. of Clyde j). 497, 



pi. IX, r. 27. C. major Greg. 1. c. f. 28. 



Rare: Stamsund r, Raftsund r, Østnesfiord r, Stene r. 



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

 Mediterranean. Red Sea. Indian Ocean. Galapagos Islands. 

 Honduras. 



ll<>(«>roil4'iM ('L. (iuclud. Discnneis Cl. 1. c. p. 180 and Artiiwncis Cl. 

 1. .-. p. 18.5). 



Valves very dissiniihir. without marginal loculifcrous rim. Up- 

 per valve costate, sometimes only striate, then with broad axial area. 



