27 



Both the herrings of three and four winter rings of the North- 

 umberland Coast shoal give indication of the immigration into the 

 shoal in August of fish with a comparatively large first year growth. 

 This change, which is followed in September by an immigration 

 of fish with a slightly smaller first year growth, is not so evident 

 as in 1914, and the size and the scattered nature of the origin of 

 the samples make it desirable that this immigration be dealt with 

 when considering the samples of 1914. 



1914. — The greater part of the herrings with two winter rings 

 in the samples of 1914 had made a growth of from 9 to 12 cm to 

 the formation of the first winter ring. These fish w^ere found in 

 the samples in varying numbers, and as has already been pointed 

 out the numbers varied with the position of capture (page 23). 

 The first year growth of these fish also varies, and the variation 

 would appear to depend upon the numbers in which they were 

 present in the samples. If the samples are arranged so that the 

 sample with the greatest number of herrings with two winter 

 rings comes first and that with the smallest number last, it is 

 seen that the growth attained up to the formation of the first 

 winter ring increases as the numbers decrease. 



Percentage at Centimetres. 



Sample. -i 5 G 7 8 9 10 11 12 13 14 Xos. 



2 115 



1 110 

 78 



10 ... — 1 3 6 12 11 27 15 17 6 1 06 



4 ... — — — -4 8 15 25 30 9 9 — 53 



9 ...— — — — 5 19 29 26 21 — — 42 



6 ...— — — — 5 10 18 39 18 8 1 39 



3 ...— — — — 6 3 11 28 36 17 — 36 



8 ...— — — — — 3 13 45 29 10 — 31 



Sample 10 is somewhat different from the other samples, 

 suggesting a mixture of fish with different first year growths. 

 It will be seen later that this sample shows a change of growth 

 for herrings with three and four winter rings. 



The herrings with three winter rings were the predominant 

 year class. The first sample exammed, sample 1, was taken 

 30th April 100 miles east of the Tyne. It contained 49 fish, 10-5 

 per cent., with three winter rings, and the growth of these fish 

 up to formation of the first winter ring is so like that for the fish 



