32 



Fishery Board for Scotland. 



the southward, of the line to which our data refer. (2) At the same 

 time these curves are by no means symmetrical, but are considerably 

 broader in the neighbourhood of their minima than of their maxima. 

 (3) While there is a tendency to a crowding together of the curves as 

 we go northward, or as the temperature falls, we see that this gradual 



N D J 



N D J 



65' 



55 



50 r 



45. 



Fig. 26.— The same for 15° W. 



tendency is evidently much more marked in the neighbourhood of 

 the minima than of the maxima ; in other words, the temperature 

 gradient from south to north is more even, or less abrupt, in July 

 and August than in early spring ; at which latter season it tends to 

 fall off rapidly in northern latitudes, i.e. in the neighbourhood of 



