of the Fishery Board for Scotland. 305 
Meyer, as we have seen, came to the conclusion that the herring at the 
end of about six months reached a length of approximately 70mm.to80mm.; 
at the end of the first complete year a length of 130mm. to 140mm., and at 
the end of the second complete year, when he supposed is to attain to 
maturity, a length of 160mm. to 170mm. 
The amount of growth in length in the first year was thus 130mm. to 
140mm. (54-54 inches), while in the second, and, be it noted, before sexual 
maturity, it was only 30mm. (1,3, inches). In other words, about 82 
per cent. of the growth in the period anterior to sexual maturity is 
represented as occuring in the first half of the period and only 18 per 
cent. in the second half, a result totally opposed to what happens with 
other fishes. 
Jenkins, as we have seen, also working on the herrings of Kiel Bay, 
by studying their otoliths, reduces somewhat the rapidity of growth 
as brought out by Meyer. He makes the sizes of the annual 
groups somewhat less than Meyer, and puts the period of maturity at the 
third year instead of the second, increasing the size at first maturity by 
some 3°0cm. He also gives the annual sizes up to the fifth year, when 
the herrings are between 9 and 10 inches in length. Thus, taking the 
average sizes as given by Jenkins, we have the following increments per 
annum before maturity. 
Year. Mean Size. Increment. aa: a Wateneien | 
a VTE ime A eee) fs yee 
1 117 117 60°3 
a 160 43 22-2 
3, | 194 34 175 
Again, if we consider the growth each year as related to the total 
growth in the five years as given by Jenkins, we have the following :— 
| 
i 
| ,. | Percentage Increase on | 
Year, Mean Length. | sppual inere Total Length at 5 
| : Years of Age. 
| Mm. Mm. | 
il ; : : 117 117 | 48°5 
Tet ye : 160 43 | 17'8 
3 194 34 14:1 
4, 221 27 11:2 
5 241 20 | 8°3 
Thus, according to these results, the herring grows in its first year 
(though not sexually mature till its third year) almost half of the total 
length it attains at the end of its fifth year. 
The conclusion, I think, is obvious, that both Meyer and Jenkins have 
jumped at least a year, and that the herring at 135mm. or 117mm. is 
much more than one year old. 
We are now tolerably well acquainted with the growth of several 
species of fish, and in all of them the growth in each year anterior to the 
occurrence of sexual maturity is fairly comparable in extent ; very often 
theamount of growth in the first year is somewhat greater than in the 
others, and it diminishes slightly with each successive year; though 
observers do not always agree about this, 
V 
