29 — 



D'ARCY W. THOMPSON 



200 



150 



100 



-50 



exist towards the extreme nortlieni and süutheni parts of the North Sea. It is perhaps 

 a little premature to draw such a chart at all for the Large Haddock, with our present 

 knowledge, but as it stands it may at least form a basis for discussion. My study of all 

 the available evidence leads me to draw a boundary line for Large Haddock between 

 areas of winter-spring maximum and summer-autumn maximum, not very dissimilar to 

 that indicated in the case of the shoals of Extra-large fish. 



While Large Haddock are caught, as we have seen, in maximum numbers in Shet- 

 land about July, and on the trawling grounds oft" the East Coast of Scotland in early 

 autumn, it is not till late autumn that we have the chief catches of Small Haddock in 

 the same region. And 



while Professor Henking 1903 1904 1905 1906 



tells us that Small Had- 

 dock reach their maxi- 

 mum in summer in the 

 Skagerrack, and in late 

 summer (July to Sep- 

 tember) in the southern 

 North Sea, there is no 

 part of our Aberdeen 

 trawling areas in which 

 we can clearly see a 

 maximum of Small Had- 

 dock at that season. 



In the areas nearest 

 to the East Coast of 

 Scotland (XXIII and 

 XXIX) we have very 

 regular curves for Small 

 Haddock, showing an 

 annual maximum about 

 the month of October, 

 but sometimes a little 

 later, especially towards 

 the close of 1902 and 

 1906 (fig. 36). The curves 

 in both areas are very 



similar, and in both cases show a remarkably high maximum at the end of 1902. In 

 area XXIX there is a steady increase from that year to the close of 1905, but in both 

 areas Small Haddock were again extremely abundant towards the end of 1906 and be- 

 ginning of 1907. If we compare these curves for those illustrative of Large Haddock in 

 the same areas we shall see firstly that the period of maximum is distinctly later in the 

 year, and secondly that the actual quantities of Small Haddock greatly exceed those of 

 the Large. 



In area XVII an autumn maximum is also conspicuous, but the shoals seem to have 

 been remarkably small in the autumn of 1905. In some of the earlier years, especially 



a 



\ 



V- 



r 



n 



•2j 



^\ 



Fig. 37. Large Haddock. Areas XIII. 



