of the Fishery Board for Scotland. 



307 



In the shallow waters on the beach, it may be entirely arrested, as with 

 small flat-fishes, while the growth of young whiting is very greatly 

 diminished — it grows at least fifteen times faster in the summer months. 

 Young herring inhabit the same coastal waters, and must be affected in 

 a similar way ; and an estimate of the average size of the one-year old 

 herring from Meyer's own observations above referred to, qualified by 

 these facts, would reduce the size very materially. 



I think there is little doubt, at all events, that Meyer's conclusions as 

 to the rate of growth of the herring, which have so long held the field, 

 are fallacious. 



Jenkin's results are based on a study of the otoliths, which, as he says, 

 cannot tell the precise age of a fish, but only within certain limits. So 

 far as my somewhat limited experience goes as to the utility of the 

 markings on the otoliths of the herring as a clue to the age of the fish, it 

 has led me to the belief that there is considerable scope for erroneous 

 conclusions, especially with the younger forms. It appears to me 

 probable, on the above grounds alone, that Jenkins has not succeeded in 

 separating the first year's fish from the second year's, and that the size 

 he gives as approximately that of a one-year-old (117mm.) is nearer the 

 size of a two-year-old herring. 



His observations on the older herrings are valuable, and it is of interest 

 to note that he makes a herring of 21 -7cm. to 22'5cm. (8| to 8g inches) 

 approximately four years old, and one of 23'7cm to 24"5cm (9| to 9| 

 inches) approximately five years old 



He gives an interesting diagram (16, p. 95) of the curves based on the 

 determinations of different observers. The point alluded to, the exaggera- 

 tion of the first year's growth, is well indicated, and the curve exhibiting 

 Meyer's results shows a deflection at the end of the first year which 

 would not apply to any other fish. 



The carves of Ljungmann (who calculated the year-old herring to be 

 from 65cm. to 90cm in length) are devoid of this, except between the 

 second and third year,f and it is noteworthy that the prolongation of the 

 curve of Ljungmann and of the curve showing Masterman's conclusions 

 meet Jenkin's curve in the fourth year. 



7. — The Scottish Collections. 



The collections have been made during the last five or more years at 

 various seasons, and mostly in Aberdeen Bay, the Moray Firth, and the 

 Firth of Forth. 



The measurements arranged in *5 centimetre groups are given in Tables 

 I.— III., appended to this paper. 



per month ; another from 30th May to the early part of October show increments of 

 •5mm. per day, or 15"8 per month ; another in July and August show increments of '9mm. 

 per day, or 28 - 5 per month ; a fourth set show increments in June and July of •66mm. 

 per day, or 20*5 per month. On the other hand, in the winter and spring, we have the 

 following : — From 21st December to end of May an increase of 17'lmm., or at a rate of 

 •107mm. per day, or 3*4mm. per mouth — most of this, no doubt, in May ; 18th October 

 to 15th January, -045mm, per day, or l'4mm. per month ; 6th November to 17th 

 December, l*5mm., or "037 per day, and Mmra, per month ; 29th November to 15th 

 January, 2'3mm., or •048mm. per day, or D4 per month. These observations are based 

 on the measurements of many thousands of fish. 



In the deeper water it may be shown that the growth in the early months is less 

 retarded, as with haddock, whiting, and witches, and no doubt also with mackerel and 

 other fishes, which withdraw to the deeper and warmer layers in winter, but, as elsewhere 

 remarked, there are not yet sufficient temperature observations with which to correlate 

 the observations on growth, those taken on the Quarterly Cruises in the International 

 Investigations being usoless for fishery investigations such as these. 



f Due to misapprehension of his measurements, a mistake also made by Meyer, who 

 took Ljungmann's measurements as measurements of the total length, whereas they 

 excluded the caudal fin. 



