26 
The peculiar age composition of the samples, the chief year-class 
being that with five winter rings, 1917, makes them different from 
any of the other samples examined. Our knowledge of the shoals 
to the west of Scotland is very small, and for Scottish waters near 
the Clyde we have no data for the growth of the herring, at least 
none which can be compared with that calculated from the scales. 
The nearest shoals for which we have growth data are those about 
the north-west of Ireland, reported upon in the Report of last 
year, and those of the Irish Sea sampled in 1921. For the purpose 
of comparison the growth of five winter ringed herrings in the 
Girvan samples, that of fish of the same age from the north-west 
of Ireland in 1921 and 1922, together with the growth of four and 
five winter ringed fish in the samples from Ardglass and Howth 
in August and September are given here. The range given for the 
different year growths is that under which the majority of the fish 
will be found. 
rish Sea. 
Clyde. N.W. Ireland. iesiiees 
5 w.r. 4woer. 
Ist year growth ... wee 8—13 10—14 7—14 9—14 cm. 
Hive! a ads sie 16—21 19—24 16—21 16—21 cm. 
Syl 5, 5s Pa Wee 21—25 24—28 21—25 21—25 em. 
4th >, . ae Per 24-—28 27—30 24—27 24—27 cm. 
Fy ea A was wars 25—29 29—31 25—28 cm. 
It is clear that the herrings of the north-west of Ireland are 
different in growth from those of the Clyde. The Irish Sea herrings, 
which were from autumn spawning shoals, have in the first three 
years (up to first maturity probably) a growth very like those of 
the Clyde, but in the fourth and fifth years the Clyde fish tend 
to be a little larger. 
Amongst the younger herrings, fish with three and four winter 
rings, in the Girvan samples a few large fish occurred, and these 
were first noticed by the larger and more boldly marked scales 
when determining age. These herrings may have come from 
Atlantic waters, but their numbers were no greater than have 
been noticed in other shoals, and their presence can be accounted 
for by the scattering of shoals after spawning and the more remote 
fish joining other shoals. 
The growth data of the Irish Sea samples for herrings with 
two, three and four winter rings show peculiarities worthy of notice. 
Fish with two winter rings were alike in the Ardglass sample of 
