63'— 64° N. 0°— 6° E. '^°^^- 



KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 36. N:0 8. 9 



During the last week of January and during February plankton was taken by the 

 Norwegian expedtion with »Michael Särs» west of Norway at about 62° — 63° N. 6° — 0° E., 

 68° N. 13°— 14° E. and at 69°— 70° N. 17°— 10° E. The collections have been examined by 

 Mr. Gran and the resiilt published in his paper »Das Plankton des Norwegischen Nord- 

 raeeres» Bergen 1902 p. 148 etc. 1 have tried to rearrange the data of Mr. Gran's in 

 order to find out the differences between the plankton coUected simultaneously off west 

 Sweden and off west Norway. I have included under February the forms found by the 

 Norwegian expedition during the last days of January *). If we classify the forms as 

 above we get: 



Plankton from 

 —64° N. 



Southern oceanic 22 



Southern neritic 8 



Northern oceanic 23 ( „„ 



Northern neritic 16 I 



The percentage of southern forms amounts thus to nearly 44 percent. Among 

 these southern forms we note Podolampas palmipes, Rhizosolenia Dehyana, Peridinium 

 glohulus and Dactyliosolen antarcticus indicating a far distant origin. Among northern 

 forms Ceratium arcticum is of particular interest, as it has hitherto never been found in 

 the Skagerak and, doubtless, derives from the N. W. Atlantic. 



Plankton at t t i 



68°— 70° N. 10°— 1 7° E. -'-°'*^- 



Southern oceanic ■'^^l ifi 



Southei'n neritic 4 J 



Northern oceanic 22 I „„ 



Northern neritic 10 I 



The decrease of southern forms as well as of northern neritic ones is remarkable. 

 The percentage of southern forms amounts now to 33 only. 



Of forms noted off the west coast of Sweden-Norway 58° — 70° N. 38 are common, 

 but 41 particular for Norway and 46 for Sweden, which raay, according to a rough 

 estimate, belong to 



Sweden. Norway. 



Southern oceanic 7 15 



Southern neritic 18 6 



Northern oceanic 3 16 



Northern neritic 18 5 



The oceanic forms ai"e thus preponderate considerably off Norway and the neritic 

 ofF Sweden, which agrees with the fact that the Norwegian stations were at a considerable 

 distance from the coast. 



*) Litoral forms have not been considered. 



K. Sv. Vet. Akad. Handl. Band 36. N:o 8. 



