Diatoms. 



219 



A. macilenta Greg. 

 &reg. Diat. of Clyde p. 510, pi. XII. f. 65. Cl. I. 



p. 121: 



Answers best to A. ergadensis Greg. 1. c. p. 512, pi. XII, f. 71. 

 which by Cleve 1. c. • ■ probably rightly is considered a 



variety of .4. macilenta. Frustule is x 19 |i, with rather narrow 

 connecting zone. 11 stria' on 10 !>-. 



Very rare: Stamsund, r. 



Distribution: Coasts of Sweden and Scotland. The Mediter- 

 ranean. Macassar Straits. 



A. euuotia Cl. 



Cl. Diat. Avct. Sea. p. 21, pi. III. B. 17. .1. cymbifera cm-. A. Schm. Atlas 



pi. 25, f. 35. 



Very rare: Stamsund, r. 



Similar to an Amphora terroris, with distinctly punctate trans- 

 verse stria 3 . Valve 80 x: 15 |i; its ends a little capitate-rostrate. 

 Stria' 7Va on 10 \i. 



Distribution: Bohuslan (Sweden). Arctic regions. Indian 

 ( icean. 



A. costata W. Sm. 



W. Sm. Brit. Diat. I. p. 20, pi. 30, f. -jrv,;. Geeg. Diat. of Clyde p. 527, pi. XIV. 



f. 99. A. inflata Grot, in A. Schm. Atlas pi. 25, figs. 29—30. 



Rare: Stamsund, r. 



Frustule 34 x 16 ;>., coarse structure; 9—10 stria' on 10 |i; 

 many longitudinal division lines. Ends protracted. 



Distribution: Coastsofthe North Sea. Mediterranean. Sumatra. 

 Eas1 coasl of America. Galapagos Islands. 



A. terroris Eheb. 



A. erebi Eheb. Microgeol. pi. 35 A, f. 2, A. cymbifera Geeg. Diat. of Clyde 



p. 526, pi. XIV, f. H7. A. Schm. Atlas pi. 26, E. 33; pi. 39, f. 18; pi. 25, 



figs. 17—19, 33-34, 36. 



Not unfrequent: Stamsund +. the 0stnesfiord r, Gaukvsero r. 

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

 Mediterranean. Macassar Straits. Gulf of Mexico. 



d. Oxyamphora Cl. 1. c. p. l^.i. 



Complex connecting zone. Valves acute with the raphe close 

 to the ventral margin. No dorsal longitudinal lines. Usually delic- 

 ate structure of transverse or slightly radiate stria' with puncta 

 arranged in undulating, longitudinal lines. Ventral side usually of 

 still finer structure than the dorsal side. Often a stauros. 



A. acuta Greg. 

 Greg. Diat. of Clyde p. 524, pi. 14, f. 93. A. Schm. Atlas pi: 26, figs. 19—20. 



Not unfrequent: Stamsund r, the 0stnesfiord r. Kaftsund r, 

 < raukvaero r. 



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

 Mediterranean. China. Straits of Magellan. 



A. groenlaiulica Ci 



Cl. 1. c. p. 128, pi. IV, f. 1. 



No stauros. 



var. 



Median stria' 12 on 10 |i, towards the ends of the valve some- 

 what closer. Puncta elongated, 10 on 10 !'-. 

 Very rare: Stamsund, r. 

 Distribution of the main species: Davis' Strait. 



A. ostrearia Breb. 



Breb. in Kctz. Sper. p. HI. A. Schmidt Atlas pi. L'H. f. 23. Van Heikck 



Rynops. p. oo. pi. 1, f. i'."> (var. typiea Cl. 1. c. p. 12!i). 



Rare: Stamsund, r; Gaukvaero, r. 



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

 terranean. Indian Ocean. Pacific Ocean. 



A. la*vis Geeg. 

 (Juki:. Diat. of Clyde p. 514, pi. .XII. figs. 74 a — .-, a Si hm. Atlas, pi. 26, f. in. 



Rare: Stamsund. r -{-. 



Distribution: Coasts of the North Sea. Pinmark. Balearic 

 Islands, .lava. 



var. laevissima (Greg i Cl, 



cl. 1. c, p. 130. Amphora kevissima Geeg. Diat. of Clyde, p. 513, pi. XII. f. l-j. 



A. Schm. Atlas pi. 26, figs. 3. 13 14. 



Rare: Stamsund r, Stene r. 



Distribution: Coasts of the North Sea. Pinmark. Sea of Kara. 



e. Amblyamphora Cl. 1. c. p. 130. 



Connecting zone complex. Valves obtuse with the raphe 

 diverging dorsally. No longitudinal lines. Fine puncta. arranged 

 in transverse striae. Structure not finer on the ventral part of 

 the valve. 



.1. obtiisa Greg. 

 Greg. Micr. Journ. V. p. 72, pi. I, f. 34. A. mum. Atlas pi. 40, figs. I 7. 



11—13. 



Very rare: Stamsund, r. 



Distribution: Coasts of the North Sea. The Mediterranean. 

 Black Sea. Red Sea. Indian Ocean. China. East coast of 

 America. 



A. speetabilis Greg. 

 Greg. Diat. of Clyde, p. 516, pi. XIII. figs, so a. c. A. Schm. Atlas pi. to. 



figs, is- 23. 



No1 unfrequent: Stamsund -f-. Stene r, Gaukvaero r. 

 Distribution: Coasts of the North Sea. The Mediterranean. 

 Indian Ocean. Pacific Ocean. West Indies. Davis' Straits. 



t. Psammamphora Cl. 1. c. p. 13^. 

 Connecting zone simple. Else as Amblyamphora. ■ 



A. ocellata Done. 



Donk. Micr. Joum. 186] in. s.) I, p. 11. pi. I, f. 11. Van Heurck Synops. p. 56. 

 pi. I. I'. 26 (var. typiea Cl. o. p. 133). 



Somewhat rare: Stamsund r, Svolvaer r. the Ostnesfiord r -(-, 

 Gaukva'ro -f-. 



Distribution: Coasts of the North Sea. Sweden. The Adriatic. 



g. Cymbamphora Cl. 1. c. p. 134. 



Connecting zone simple. Valves of rather delicate structure. 

 No longitudinal lines. Raphe close to the ventral margin. 



A. angusta Greg. ■ Cl. 

 Cl. 1. c. p. 135. Greg.? Diat. of Clyde p. 510. pi. XII, f. 66 (var. typiea Cl.). 



Rare: Stamsund. r. Hardly Gregory's species. 

 Distribution: Scotland. Arctic regions. East coast of North 

 America. West Indies. 



