58 
Some of the young herrings join the commercial shoals in 
their third year, but there is little evidence that fish of this age 
are ever present in sufficient numbers to make any considerable 
difference in the catches landed. Although some thousands of 
herrings have been examined from waters about the west, north- 
west and east coasts of Ireland, Stornoway, the Shetlands, north 
and east of Scotland and south to Yarmouth, very few herrings 
with ten winter rings have been found in the samples, and the 
number with nine winter rings has not been great. For a period 
of six years the herrings arising from one spawning are of import- 
ance in the catches, and throughout that time their numbers 
gradually decrease. Norwegian herrings and those found about 
the Faroes and Iceland are caught in fair numbers at a greater 
age,* but no sample of British herrings has been examined that 
showed fish with ten or more winter rings worthy of any considera- 
tion from a commercial point of view. 
Spawning shoals, autumn and spring, and shoals of full herrings 
off Yarmouth contain more of the older fish than do the summer 
feeding shoals. But these shoals are added to yearly, and their 
numbers are increased by additions from the summer feeding 
shoals of developing herrings which are, most of them, in their 
fourth year. 
It is hardly possible to exaggerate the importance of herrings 
in their fourth year, and the first evidence we shall have of the 
presence of a good year-class in the fishery will be from the 
increased catches made from summer feeding shoals. 
The term year-class is very convenient, but may be misleading. 
British herrings spawn in both spring and autumn, but young 
arising from both these spawnings in the same year cannot be 
referred to the same year-class. Last year, in October, large shoals 
spawned off Yarmouth and Lowestoft. When the products of 
this spawning enter our commercial shoals, in 1925, they will be 
referred, from age determination by means of the scales, to the 
1922 and not the 1921 year-class. For convenience the term 
year-class will be used, but it is to be understood it refers to the 
products of a spring spawning together with those from an autumn 
spawning in the previous year. 

* Pub. de Cire., No. 43: 
