CHAPTER VI. 



WHITLING. 



In brackish or salt water, then, the young fish, once they have 

 descended as smolts, whenever that may be, continue their existence. 

 While merging insensibly from smolts to whitling they finally lose all 

 traces of the parr state, their scales become more firmly set — but not so 

 much so as in the mature state — and, if the scales are now removed, no 

 parr marks will remain visible on the skin. The fins and tail become 

 stronger and the colouring of the upper body of the fish becomes much 

 darker — the small dark head giving origin to the Loch Lomond name 

 of " black-neb " (i.e., black nose) for the fish at this stage. I insert a 

 drawing of a typical whitling (Fig. 7,'/) which I caught at Luss on 20th 

 September, 19 15. The fish weighed fib. and was 12^ ins. long, and 

 6j ins. in girth. 



The richer quality of marine feeding makes for rapid growth and 

 the smolt of seven, eight or nine inches in length in about three months 

 becomes a whitling measuring twelve, thirteen or fourteen inches. In 

 three months, at least, they are ready to undertake their first return to 

 fresh water. One can fix this period of three months with exactitude, 

 for, just as the main body of smolts practically everywhere descends in 

 April and May, so the main body of whitlings in most rivers ascends 

 in July and August. So general is their habit in this respect that the 

 sea-trout of this small class are popularly called Lammas trout. 



Confirmation of the time of return is also obtained from the scales, 

 and I could show several scales of whitling clearly illustrating it. But 

 I shall content myself with giving the reproduction (Fig. 38) of a scale 

 of a fish weighing ijlb. which I caught in Loch Lomond on 4th 

 September, 19 14. I had noted it at the time of capture as " a beautiful 

 clean whitling." The fresh-water residence in this instance is almost 



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