KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 36. N:0 8. 13 



throughout both in a hydrographical and biological respect. The result of these coinbi- 

 ned researches have been laid down in a sepavate publication by Prof. S. O. Pettersson 

 and tho present author. 



No samples were collected at Väderö but throughout the month at Måseskär. The 

 plankton from Måseskär can be classified as follows. 



Remnants from 

 July. 



Southern oceanic 9 7 



Southern neritic 9 3 



Northern oceanic 2 7 



Northern neritic 2 2 



New. Total. 



28 



13 



The predominant plankton-type was the ^r^pos- plankton. 



Not less than 75 different forms were noted in the plankton of the North Sea and 

 they have been classified as follows: 



Southern oceanic 24 ( 



Southern neritic 24 j 



Northern oceanic 17 ( 



Northern neritic 10 I 



Total. 



48 



27 



September 1901. 



Samples were collected at Måseskär throughout the month, but at Väderöboda at 

 the end of the month only. Most forms were the same as in August but their abundance 

 had changed somewhat. The statistics give the following result: 



Remnauts from 

 August. 



Southern oceanic 14 1 



Southern neritic 12 4 



Northern oceanic 3 4 



Northern neritic 5 7 



October 1901. 



New. Total. 



31 

 19 



Samples were collected throughout the month both at Måseskär and at Väderö- 

 boda. The plankton was on the whole very rich both in individuals and in number of 

 species, the latter amounting to 82. 



Classified as before we get the following result. 



