KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 57. N:Q 7. 



47 



by the most varying play of the currents, especially in the depth. This result is by no 

 means unexpected, since we know from recent hydrographic works what huge subma- 

 rine waves are pulsing in the Ocean towards our shores. 



According to the table 70 above, the peridinians and infusorians exhibit a uniform 

 spreading throughout the vertical columns as well as the diatoms, and I could here equally 

 calculate average-numbers for the whole of the water-kind concerned. Still, the rapidly 

 developing infusorians have distinctly begun to increase in number at the uppermost 

 level of 10 m, observed in this water. From this slight increase t here is, however, a far 

 step to the still much richer surface-fauna. Also the peridinians tabelled are, with an 

 exception for the Getatia, considerably more numerous in the uppermost layer than in 

 main water-masses of this station. But as we know from previous series, all these organisms 

 are regular and trivial inhabitants of our colder waters in spring. 



Table 71. S. Skag. 8. 58° 10' N., 9° 18' E. 18. IV. 1914. 



-»a 



O, 



Q 



S £ 



<D 3 



O 



o 



-•a 



C 



"3 



t» 



>> 



CO 



C 

 O 



Q 



Thulassiosira 

 Norden- 

 skiöldii 



Sceletonema 

 costatum 



( ruinardia 



flaccida 



Eucampia 

 zodiacus 



Stephanop- 



yxis turris 



Biddulphia 

 sinensis 



Rhizosolenia 



alata f. 

 eorpulenta 



Rhizosolenia 



hebetata 

 f. semispina 



Leptocylin- 

 drua danicus 



to 



2 E 



<e 3 



o -t» 



° fe 



CD « 

 03 C 

 JS O 



o « 



Thalassio- 

 thrix lon- 



^issima 



Thalassio- 



thrix nitz- 



schioides 



Diatoms 



total 

 numbers 







6,58 









80 













680 



1,260 



240 



+ 40 





20 



2,490 



10 



5,43 



34,36 



27,08 





280 











10 



20 



86,600 



620 



40 80 



88,570 



20 



5,94 





— 



260 



80 





640 



420 





330 



40 



173,000' 



530 



160 



179,320 



CO 



6,38 



34.01 



27,22 



5C.ii 



80 



20 







20 



10 



20 



2,560 



700 

 + 180 



200 



60 



5,620 



40 



7,01 



34,79 



27,26 



(i4i i 





40 







360 







72" 



140 



160 



[,780 



5,520 



00 



7,03 



34,81 



27,26 



40 

















4n 



40 



20 



340 



650 



100 



7,05 



34,87 



27,33 



30 



480 









10 









W 



10 



160 



850 



150 



7,02 



34,94 



27,39 





80 























470 



200 



7,00 



35,08 



27,50 

























10 



170 



644 



6,03 



34,97 



27,55 



























100 



At this deepwater-station in the Norwegian f urrow, though the water is both warm 

 — 6°,4 to 7°^ — and very salt under a limit situated about 30 m below the surface, it is 

 still totally different from that of the preceding station. Poor in plankton on the whole, 

 it contains in its uppermost part mainly some dominating species of the richer surface- 

 water, first and foremost Leptocylindrus, Chaetoceras contortum and ThdUissiothrix nitz- 

 schioides, as well as remaining indigenous Thalassiosirae, this vegetation on the whole 

 arriving here from the Baltic surface-water by sinking. 



The 20 m-sample is in several respects a most interesting one, and deserves to be 

 treated by itself. Here is a curious mixture-layer, holding at once the Leptocylindrus- 

 formation, just spöken of, and relatively high numbers of such southern forms, generally 

 rare with us, as Eucampia zodiacus, StepJianopyxis turris and Rhizosolenia alata f. eorpulenta. 

 It is not easy to unravel the origin of these forms, that are not present in the formation 



1 For a great part forming spores (or getting destroyed by a parasite?). Cfr part II. 



