JS. Weissei ((i rin.)? 

 Triceratiwn UVissci (Ikin. in A. Schmidt Atlas pi. i)n, f. 2. 



A specimen very similar to the (ii?ure referred to (from Arch- 

 angel) was found: Stene, r r (a single specimen). Rather coarse 

 radiating- structure of puncta (pearls); about rows on 10 |i. Large 

 circular central space without jjuncta, only one or two near the 

 periphery. Side of the triangle .57 ;a. 



Might also belong to tlic genus Triiuicrid. I iiave not seen 

 a side view of the valve. 



Distribiitmn: Only known fossil (Simbirsk, Archangel). 



Isfliiiiia A(i. 



/. ciicrvis Khrr. 

 KURn. Inf. i>. 209, 1)1. Iti, f. (i. Van Helkck Svuops. pi. 96, figs. 1—3. 



Rather frequent: Moskenstionnnen ir, Stamsund r, Svolvær r, 

 Raftsund r, Brettesnes — Skroven i". Stene r. More frequent on algæ. 



Distribution: Coast of Western Europe. Finmark; Spitsbergen 

 (Clkve). West Indies; Honduras. 



KuTZ. BaciU. p. 137 



I. nervosa KCtz. 

 19, f. 5. Van- Heirck Tr 



Diat. 4.52. pi. 34, f. 891. 



Very rare: Raftsund r. 



Distrihdion: Western Europe. Denmark. Arctic regions. 

 Honduras; San Francisko. Kertruelen. 



6. Chætocereæ. 



Rartei ia»>itrnni varians Laid. 

 Lacd. Trans. Micr. Soc. 18ti3, XII, p. 8, pi. IK, figs. l-(5. 



Derived from the plankton. 



Very rare: Stene rr. 



Distribution: Neritic plankton species, from the western coasts 

 of Europe. Warmer coasts of the Atlantic, Indian and Pacific 

 Oceans. Rare oflf the west coast of Norwav. 



Chætoeeros Ehrb. 

 C. atlanticus Cl. 



Cf. above p. 1(30. 



Derived from the plankton. 



Very I'are: Gaukværo r. 



C. contortus Schutt. 



Cf. above p. 101. 



Thickened horns, most probably belonging to this species, is 

 found now and then in the bottom samples, though seldom. Un- 

 doubtedly derived from the plankton. 



C. diadema (Ehrb.) Schutt. 



The characteristic resting spores of this species ('Si/ndmdrium 

 diadema Eheb.) occur rarely: 



Stamsund r, Svolvær r, Gaukværo r. Derived from the plankton. 



Distribution: Ch: above p. 101. Syndendrium diadema Ehrb. 

 also in Peru guano. 



Stcplianogonia Hmrb. 



A specimen very similar to <S'. acUnuptijclias (Ehrb.) Gri-n. 

 in Van Hkurck Synops, p. 83.-,, ligs. 2—4 was found in the sample 

 from Moskenstrømmcn. 



Nearly circular. Diameter 70 \y. 1.5 radii. On the smaller 

 upper disc, a coarse spine seems to be found. In other respects 

 corresponds very well to the figure referred to. 



Stcphanoi/onia poli/gona Ehrb. seems to be a similar form, 

 perhaps the same. Both are probably resting spores (cfr. Schutt 

 in Engler and Prantl, Naturl. Pfianzenf., Th. 1. Abth. 1 b. 

 p. 147). 



Distribution: ]>oth .species mentioned are known from ,,North 

 America" (Ehrenberg). The figure mentioned represents a fossil 

 specimen from Nottingham deposit. 



A. SCHM. Noids. Dii 



Pyxilla baltica (Srls. 



111. .S, f. 2.5. Van Hel-rck Synops, pl. 8.3, f. 2. 



According to the figure in Hensch (oter Ber. Komm. Kiel, 

 pi. V, f. 38 c) Pyxilla baltica must be the resting spore (endocyst) 

 of Ehizosolenia setiyera Brightw. 



Undoubtedly derived from the plankton. 



A'ery rare: Rhizosolenia setigera is a neritic plankton diatom 

 from the coasts of Europe (Western E., Skagerak, Mediterranean). 

 Pacific Ocean, Indian Ocean; north of South America. Pyxilla 

 baltica is known from the Baltic, and fossil from Simbirsk. 



11- Fe-n -n a-fcæ Schctt. 



7. Srnedreæ. 

 Sjiu'dra. 



a. Eusynedra V. H. 



S. affijtis KL-TZ. 

 KuTZ. Bacill., p. 68, pi. 15, figs. 6, 11. Van Heurck Synops, pl. 41, l'. 13. 



var. tabulata (Kltz.) V. H. 

 V. H. Synops, pl. 41, f. 9 a. Si/nedra t. Kutz. 



Very rare: Svolvær r, Østnesfiord r. 



Distribution: Frequent on the coasts of Europe. Arctic 

 regions. 



S. kaiutscbatica Grun. 

 Gkun. in Cl. et grun. Avkt. Diat. p. 106, pi. VI. 



Tar. intermedia Grun. 1. c. f. 111. 



Very rare: Stamsund r. 



Distribution: Kamtschatka, Finmark, Spitsbergen, Greenland, 

 Kara Sea, East Cape. 



S- ulna (NiTzscn.) Ehrb. 



Van Heurck Synopsis pi. 38, f. 7. 



Fresh water species. 



Very rare: Svolvær r. 



Distributio)i: Common fresh Avater .species. 



