394 



stations of the second series (91, 12 — 20) lie west of Reykjanæs 

 Ryg between this barrier and Greenland and the third series 

 is obtained from the Davis-Strait. The alkahnity of these 

 parts is markedly lower than that found east of the great 

 barrier. In the present state of our knowledge I cannot give 

 any explanation of these differences but I think it probable that 

 they may be due to some bottom-influence. 



2. The organic life has, 1 think, a comparatively small 

 influence upon the alkalinity. Nothing definite can, however, 

 be said about it quantitatively. It may be summed up as 

 follows : 



a. Formation of organic substance. Among the mineral 

 components absorbed by plants, when growing in a culture- 

 solution, the acids are slightly in excess of the bases and the 

 alkahnity of the remaining liquid therefore increases. We do 

 not know whether this also holds good for marine macroscopic 

 and microscopic plants on which no experiments have been 



