b. Diatoms in Bottom Samples from Lofoten and Vesteraalen. 



1-',, .loiUilCNSKN. 



Ill the I'ollowiiiL;- paiios ail aci'ount is i.'iveii ot tlir diatiniis coii- 

 taiiu'd in some bottom samples tVom the t'ollowiiii;- loealities in Lo- 

 foten and Vesteraalen: 



Mosiicnstromincn, — 180 m. (tiiL'ctlier witli idanktoii), 



ytamsund, 0—150 ni. (togetiier witli iihuiktoiil, 



Svolvær harbour, 10—15 m., 



The Ostnes Fiord, 10-20 m., 



Brettesnes — Skroven, 350 — -I0(t lii.. 



Mouth of the Raftsund, 250—300 m., 



Stone in Bo, 10 m., 



Gaukværø, 0-180 m. (together inth plankton). 



Two of these, the samples from Brettesnes — Skroven aud from 

 Raftsund, were poor and consisted pei'haps only of dead specimens, 

 a good many of which naturally originate from the plankton. The 

 samples from Moskenstrommen, Stamsund and Gaukværo were taken 

 together with plankton. 



The working through of bottom samples is a very troublesome 

 and lengthy task, when it is done as it should be. As there was, 

 however, not time enough to investigate the samples in the manner 

 I consider the right one, and as — on the other hand — it was 

 of some importance, to be able rightly to interprete the plankton, 

 to gain a preliminary knowledge of the bottom flora, I have con- 

 tented myself with the method usually adopted, and have studied 

 the species from the valves in slides. For this purpose the material — 

 together with a richer one from the west coast of Norway — has 

 been prepared as slides by Mr. Thum of Leipzig, in his well-known 

 perfect way. 



For this reason, it has not been possible to discern between 

 living (recent) and fossil species. 



The species occurring in the plankton are in detail dealt with 

 in another chapter of this work (pp. 90 — 108). Nevertheless, to 

 avoid arbitrariness, I have not omitted the plankton species, but 

 have in such cases mentioned them as originating from the plankton. 



List of the species observed. 

 X- Cen'bx'±cæ Schutt. 



I. CosciuodJsceæ. 



CoseinodisciiK Ehki!. 

 C. nitidus (iHEO. 



Cf. above p. 95. 



Somewhat rare: Moskoiistrommcn r, Stamsund r, Raftsund r, 

 Stene r, Gaukværo r. 



Distribution: Western Europe: JJalcai'ic Islands. Gi'eenland 

 and Finmark (Cleve). Warmer coasts of America, Asia and 

 Australia. 



C. niqioUiiiin Kimii. (1844). 

 KiiRB. Jlikingeologie pi. 35 A, XXU, f. 4. 



v.'ir. couipacta Rattr. Rev. of Coscinod. p. 579. 

 C. scintilUoiii ((iuKV.) .\. Schmidt Nords. Dial. p. iM, pi. ;}, f. ;33. 



Differs from the main species (= ('. scinfillitiis Ghev.) in 

 having the puncta distinctly smaller towards the margin, more 

 numerous radial rows, the shortened ones being longer tiian usual. 

 Probably is a separate species. 



Rare: Mosken.strømmen -f, Stamsund r, Svolvær r, Stene r. 



Cosc. nitvhis A. Schm. Nords. Diat. pl. Ul, f. 32 does not 

 sho\\- the irregular distribution of the puncta that is characteristic 

 of the preceding species. This form occurs in my material together 

 with the one figured 1. c. f. 33 and has a similar radiate structure, 

 only much coarser. 



Dlstrihution : The variety is only known from Solsvik (west 

 of Bergen, Norway). The main species, which has not been found 

 by us, occurs in the antarctic regions. 



C. concavtts Ehrh. v Greg. 



Greo. Diat. of Clyde 1857. p. 500, pi. X, f. 47. Eiirb. Mikro;;eol., pi. 21, f. i; 



mm pi. 18, f. o8. 



Hardly belongs to the genus Ccscinodiscus. Rattkay 1. c. p. 

 470 remarks that the girdle aspect of this species answers to E)t- 

 didya oceanica Ehkb. (cfr. Mikrogeologie pi. 35 A, XXVIII figs. G, 

 7; A. Schmidt Atlas pi. 65, figs. 10—15). 



Very rare: Gaukværø r. Diameter 86 |i; 2 areoles on 10 jx; 

 border sharply defined, nearly 3 \i. broad. 



DisUihution: Western Europe; Balearic Islands, Black Sea. 

 Sea of Kara (Cleve). Warmer coasts of America and Asia. 



C. leptopns Grin. 

 V.\N Heurck Synops, pl. 131, figs. 5—6. 



Rare: Raftsund r. Diameter 55 [j.; 5 areoles on 10 n. Re- 

 markable for the minute areoles on the border, like those in the 

 genuine C. Vmeatus Ehrb. It differs on the whole from the latter 

 species only in possessing the pseudonodule. 



Coseinosira polycliorda Gran and the variety of Coscinodiscus 

 linentKs mentioned below have a much liner structure and less re- 

 gularly straight rows of areoles. 



Distribution: Mediterranean. Southern Atlantic, Pacific Ocean, 

 Indian Ocean. 



C. lineatiis Eiiiu!.. rar. 



Cf. above p. 92. 



Kare: Stamsund, r. Finer structure than in the genuine C 

 lineutiis. Small; TVs — 8 areoles on lo \>: Border narrow, striate, 

 15 striæ on 10 [i. Areoles near the border somewhat smaller. 

 Secondary rows somewhat flcxuose. 



In the sample from Svolvær a very similar specimen was 

 found, only with a little finer structure and marginal spines. This 



