of the Fishery Board for Scotland. 299 
50mm. They are not found in the spring or summer, but recur in the 
autumn, with a length of about 80mm., which is increased to 100mm. 
by the end of the year. Nout one year old Masterman thinks they are 
probably about 60mm. (23 inches) long, 
In the case of the autumn herrings, the occurrence of newly-hatched 
larvee extends over August and Se ptember, the spawning period being 
thus of shorter duration. ‘The larve are somewhat shorter than the 
spring ones, averaging between 5mm. and 6mm. 
The following Table gives Masterman’s estimate of the growth from 
month to month of the spring and autumn herrings, after hatching :— 
Month. | Spring. | Autumn.| Month. | Spring. | Autumn. 
Mm. Mm Mm Mim 
1 15 14 8 47 43 
2 20 19 9 50 |) 475 
3 27 23 10 54 52 
4 30 27 11 58 57 
5 35 30 12 62 61 
6 40 34 18 87 88 
7 44 38 20 98 
24 113 
Thus, according to Masterman, the autumn herring at two years of 
age is rather smaller than the one-year old spring herring of the Baltic, as 
Meyer has determined it. The rate of growth of the spring series is 
about 4mm. to 5mm. per month, while in the winter months the growth 
of the autumn herring in the early stages is retarded (3mm. to 4mm. per 
mouth). The largest specimen in the collection measured 134mm. (53 
inches), which would be about 273 months old and belong to the autumn 
brood. In his later work in conjunction with M‘Intosh (17a, p. 422) 
rather a different opinion is expressed. It is there supposed that the 
herring attains sexual maturity at a length of 8-9 inches and probably 
during the third year; and it is stated that 3 inches and 5 inches may 
be taken to represent a rough average of the size of a herring when one 
year and two years of age respectively. 
The growth of the herring on the Scottish coast has also been considered 
by Cunnitigham (18, p.162). ” He is of opinion that the herrings 33-5; inches 
long (82mm.to 133mm.) taken in considerable numbers in December, i in the 
sprat fishery in the Firth of Forth, are derived from the spring herrings 
that spawn at the Isle of May, which would give them an age of about 
nine months. 
At Plymouth, a large number of small herrings from 4°3 to 5°5 inches 
long, taken in May, are supposed by Cunningham to be year-old fish, 
derived from the spawning in February and March in the previous year. 
From the above review, it is apparent that very different opinions 
are held as to.the rate of growth of the herring and the size and age 
when it reaches the mature condition. 
2.—Tue Size oF THE HERRING WHEN IT FIRST ATTAINS MatuRITyY. 
The observations made by myself as to the size when maturity is 
attained lead to the conclusion that the herring on the coast of Scotland 
does not spawn until it has reached a larger average size than most of 
those given above. 
