394 Part III. — Ttventiei/i Annual Report 



series present ia the precediug autumn, the bulk of the shoal having 

 probably risen from the bottom and escaped capture. If we construct 

 such a series, with the usual range, in front of the one beginning about 

 24 cm., viz., back to about 140 mm., then the mean-size of these whitings 

 when about a year old, in May, would be approximately 184*5 mm., or 

 1\ inches, the smallest measuring about 5| inches and the largest about 

 9 inches. On this hypothesis, the growth in the five months (about 155 

 days) December to May, would amount, on the average, to about 59'4 mm. 

 (2| inches), compared with the 17 or 18 mm. (j-jt inch) of increment for 

 the corresponding series for the same time in Aberdeen Bay ; and the 

 deep-water whitings in May would correspond in length to those got in 

 Aberdeen Bay in July. The increase is great, but in the case of the 

 haddock, where the series are somewhat better represented in December 

 and May (p. 404), the increase in the five months amounted for this series 

 during the same period to 62 mm. in the deep water off the Shetlands and 

 to 35 '3 mm. for Aberdeen Bay, calculated in the average size derived 

 directly from the measurements. Since the whole annual increment 

 between Series I. and Series II. in the deep-sea haddock, calculated on the 

 December curves (which are extremely good), is 128'9 mm., it follows that 

 the remaining 69 "5 mm. must be made up during the other seven months 

 of the year, from the middle of May to the middle of December, so that 

 the winter and spring growth in the deep water is approximately at the 

 same rate as during summer and autumn. This forms a marked 

 contrast to the growth in the two seasons exhibited in Aberdeen Bay, 

 and is, no doubt, due to the greater uniformity of the conditions 

 throughout the year, and especially to the much slighter seasonal 

 changes of temperature that occur in the deep northern waters. In 

 connection with this it may be further remarked that the distinctive- 

 ness and separation of the early Series I. and II. are much greater in 

 the deep water than in the inshore waters, and this is true not only of 

 the whiting, but also of the haddock, the Norway Pout, and the long 

 rough dab. 



The range and relative growth of the 1st Series of Whitings at the 

 different dates is represented in the adjoining figure. 



August, September. 

 October. 



Docemlier. 



In its second year the growth of the whiting is also rapid, and in 

 inshore waters, as Aberdeen Bay, it exhibits the same variation with the 

 season as in the earlier series. 



In the following Table I have given the particulars of the ranges and 

 averages in the various months, tracing the series from the early part of 



