Errata et Addenda. 



Pag. 96, col. 2, line 28, for T. decipiens Grun. read: 



T. decipiens (Grin.). 

 Pag. 10.5, col. 1, after line 2 add 



(Plate VII, fio'. 2(5). 



Pag. 108. col. 1. before 11. E'ex'±ca-±n±ales add: 

 Tropidoneis parallela Jprg. n. sp. 

 (Plate Vir, fig. 16). 



In the plankton tables Amphi2}rora parallela n. sp. 



Shape of the cell in side view: Linear, or slightly oblong, not 

 constricted in the middle, narrowing off a little towards the rounded 

 end.s. Central nodule rather indistinct; terminal nodules, however, 

 very conspicuous. 



Vahe: Linear-Lanceolate, ends subiostrate (truncate). Median 

 line straight, central. Central nodule small, terminal nodules close 

 to the ends. 



The median part of the valve seems to form a rather high, 

 linear keel, about so broad as Vs of the valve. 



Stnicfare: Fine transverse striæ, not distinctly punctate, 17 on 



10 :j.. 



Dimensions: Length of the valve 67 — 70 'i-, breadth 12 i^. 

 Breadth of the cell (frustule) 18 \y.. 



This species resembles Amphoropsis recta Gkun. (Van Heueck 

 L. 89, p. 266, tig. 55) and Amphij^-ora plicata var.? suhplicata 

 C4run. (L. 48, p. 65, pi. V, fig. 88). It diifers from both in having 

 the frustules quite inconstricted in the middle. On the contrary, 

 the cell is often somewhat broader (higher) here. Besides, 1 have 

 never seen an asymmetiical valve, like that characteristic of Am- 

 phoropsis recta. I have, however, only once succeeded in getting a 

 valvar view of it (tig. 16 b), as in the preparations it is nearly 

 always found lying on its side. 



Cleve refers (L. 24:,i).2H)AmphiprorajiHcata\fiv.'^sut)pUeata 

 Grun. as a variety to Amphoropsis recta (Tn/pidoncis recta Cl.) 

 without mentioning the shape of the valve. 



The above species seems to be a true plankton form. It has 

 very thin (slightly siliceous) valves which easily are deformed on 

 being ignited on the cover-glass. It generally occurs solitary or by 

 twos, very seldom forming a short chain of some few individuals. 



On the whole rare and sparse, only observed during the 

 diatom inflow in liJOO: Høla, Svolvær, -"/■■„ 0—140 m.; Østnes- 

 fjord 1 and III, "Vs, 0—25 and 0—1.30 m.; the Vestfjord, =7:i, 

 0—25 m.; the Skjerstadfjord IV, V4, 0— 330 m., and XII, 0—500 

 m.; the Seivaagen, V*, 0—20 m.; the Saltenfjord II, ^4, 0—50 m.; 

 the Foldenfjord I, "A, 0—100 m. Also in P.aront's Sea, 71° 48' n., 

 49" 38' e., S/S Heimdal ^'/s 1900. 



Undoubtedly an arctic species. 



Page 100, add: 



C. scolopendra Cl. 



As endocysts, resembling those of C', cinctus, are found, the 

 older name for the latter species, C incurvus Bail., cannot be used. 



Very rare and sparse: Sea off Inge, ^V4 1899, 0—300 ra.; the 

 Porsangerfjord, -V4 1899, 0—75 in. 



Distribution: More frequent on the west coast of Norway. 

 According to Cleve a northern (boreal) neritic species. Only once 

 (in October 190(>) found near the Pærø Isles. (Ostenfeld). 



Page 105, after Naviculeæ add: 



Pinnnlaria quadratarea (A. Schm.) Cl. 



Cl. L. 25. p. 95. Naricnla quadratarea A. Schji. L. 127, 

 p. 90, pi. II, f. 2(;. N. pinnularia Cl. L. 28, p. 224, pi. IV, 

 fs. 1—2. 



Occui's only accidentally. No true planktonform, but rather 

 frequent in bottom samples from both the west and the north coast 

 of Norway. 



Page 99, before B. stijUformis, add: 

 R. obtusa Hens. 



Hensen L. 87, p. 86, pi. V, f. 41. E. idata rar. truncafa 

 Gran L. 64, p. 6, pi. IV, f. 67. 



Not always easy to disthiguish from B. aliita (cfr. Ostenfeld 

 L. 116, p. 569). 



Very rare and sparse, only in 3 samples: Stene in Bø, '% 

 1899, m.; the Porsangerfjord, ^'A 1899, 0—75 m. and 200—100 m. 



Distribution: According to Cleve, Gban and Ostenfeld a 

 boi'eal oceanic species, occasionally numerous round the Færøes, 

 Iceland and in the Norwegian Ocean, up to the north of Spitz- 

 bergen. Is wanting on the west coast of Norway (1898). In large 

 numbers in arctic water between Tromsø and Jan Mayen 1897, 

 also numerous round Jan Mayen 1897—1898, and near Spitzbergen 

 1899—1900 (Jørgensen L. 92). Seems to me to be an arctic 

 (oceanic) rather than a boreal species. 



Page 104, col. 1, line 10, for PI. VI read PI. VIL 

 Pag-e 105, col. 1, hue 2, add: (Piate vii. tio-. at;). 

 Page 109, col. 1, line 36, for (Dies.) Clap, et Lachm. read 

 (Clap, et Lachm.) Dies. 



Pag. 119, col. 1, line 49, for SO read 86. 

 For Midva-rfjord everywhere read ilisvanfjord. 



