teiii|ieriite Atlantic, and only occasiunally and cMcptionallx carried 

 as lar north as Lofoten. 



Docs not occnr on the west coast of Noi'wav. 



l*«Ml«tlaiii|»a>> ji:ilmii,cs Stkin. 



Very rare and only singly: The Vest Fiord I, '',i 1S99 

 0—50 m. and 0—180 m.), Tranodybet -/z 1900, 0— (i(iu m. and 

 The Folden Fiord "/-i l^'OO, 0—530 m. With us a foi'ni which is 

 only accidentally and exceptionally broui;ht in from the south. 



Disiribittioii : Oceanic form, widely distributed in the tropical 

 and temperate parts of the Atlantic, northwards in the summer 

 (cfr. Clevi: !,. lu, p. 27r,) right up to near Iceland. On the west 

 coast ot Norway very rare and only singly. Seems to be cosmo- 

 politan in all the warmer seas, as it is also mentioned from the 

 Mediterranean, the Ked >Sea. the Indian Ocean and the Pacific 

 Ocean. 



Oxvtoxi 



diplocoitns Stei.n 



Only one specimen found (therefore determination not fully 

 reliable): The Skjerstad Fiord V, '74 1900, ti — 420 m. 



Like the foregoing, an accidental southern form. 



Distribution: Southern oceanic form, from the warmer parts 

 of the temperate Atlantic. On the west coast of Norway also only 

 once found in 1898. 



P.vi-opliarn.>< horologium Steix. 



Kare and scarce; found, however, in several samples. Seems 

 to be entirely absent during the spiing diatom inflow; then it was 

 only found in one deepwater sample from one of the flords: The 

 Folden Fiord 7* 1900, 500—400 m. 



Distribution : Southern form, according to Cleve, properly a 

 tropical oceanic foi-m. Probably has a wide distribution in the 

 warmer temperate waters of the Atlantic. As it is easily over- 

 looked, its distribution is hardly yet quite sufficiently known. 



Its comparative fi'equency on the coasts of Norway might sug- 

 gest either that it is able to thrive well in the coast waters at 

 our latitudes, or that thci-c are two diti'erent species of which the 

 one is a tropical oceanic one not occui'iing with us. 



<Mon.vanlax spinifera (Dies.) Clap, ot Lachm. 



Very rare and scarce, only found in some few of the samples: 

 The Ogs Fiord, "A 1899, 0—90 m., in the sea off Senjen 1^4 

 1899, 0—80 m.. Hola =73 1900, 0—50 m.; Bålstad I, ='/:. 1900, 

 0-50 m.; The Skjerstad Fiord XII, 0—500 m. 



Distribution : Is considered by Cleve to be a neritic species. 



There seems to be, judging from Cleve's accounts (L. 40, 

 p. 249), two different species, a boreal or ai-ctic species and a more 

 southerly one, which is probably oceanic. Its occurrence on our 

 northern coasts also suggests that our species is oceanic. 



Grax (L. 67) mentions Gonyaidax spinifera as occurring in 

 small numbers in the Eids Fiord (Nordland) in the months of 

 July— September 1898—99. 



Two species occur also on the west coast of Norway (cfr. E. 



Jokuensen 1.. 91, p. ;J4). The lesser of these is al.so found in the 

 Baltic. 



l'loto«-<>i'aliiini rttiviihiUim {Va.sv. .t Laciim.) Bltschi.i. 



Very rare and genei'ally in small nnmheis. As it is, however, 

 so small that it is not retained by the net, it is probably found 

 more frequently than appears. 



Was found in 1900 principally in deep water samples. 



Distribution: Not sufficiently known. Is considered by Cleve 

 (L. 40, p. 277) to be a neritic northern or arctic form. It is found 

 most frequently on the American side. On the west coast of Nor- 

 way in 1898, generally A-ery scarce. 



i>i|>lo|>Nalis Icnticitla liKm.ii. 



Rather fre(iuent, especially in tolerably deep water, often i-ather 

 numerous. Seems to be altogether absent during the spring diatom 

 inflow. Gran (L. fi7) found it at several places on the northern 

 coast of Norway in the months of .July— October 1898—99, but 

 generally in very small numbers. 



Distribution: According to Cleve, a southei-n oceanic species, 

 widely distributed in the warmer parts of tlie temperate Atlantic. 

 Also known from the North Sea (from The Enghsh Channel, Feb. and 

 May 1903) and the Cattegat. Rather frequent on the west coast 

 of Norway (1898). 



Peridiiiiaiii Ehub. 

 P. depressiun Bail. 



Very frequent, often in quantities. Much scarcer during the 

 .spring diatom inflow. Grax found it at Bodti and in the Eids 

 Fiord in the months of July— October 1898—99 frequently. 



Distribution : Seems to be an arctic and boreal neritic species, 

 which is stationary both on the noith and west coast of Norway. 

 Widely distributed in the colder pai't of the northern Atlantic, 

 chiefly on the coasts, from the American side, to Greenland, Ice- 

 land, (Faeroe Islands, the North Sea), NorAvay and right up to 

 Spitz-bergen and Novaja Semlja. 



P. oceanicum Vami()f. 



Surely a good species. 



Was not so rare in 1899, but always in small numbers. Not 

 noticed in 1900. Absent during the spring diatom inflow. 



Distribution: Southern oceanic species which, according to 

 Cleve is widely distributed in the warmer part of the temperate 

 Atlantic, and penetrates northwards right up to Greenland. Very 

 rare and scarce round the Faeroe Islands and on the west coast 

 of Norway. Also known from the Red Sea and the Indian Ocean. 



P. divergens Ehbh. 



P. knticitlare (Eiirb.) Jurg. L. 91, p. 37. 



As this .species is now in most works on plankton mentioned 

 under the name of P. divergens Ehrb., I have, at any r^te pro- 

 visionally, found that I ought to use this name instead of the more 

 explicit one, P. hmticidar.'. I hope in a later Avork to be able to 



