534 Part IIT —Twenty-fourth Annual Report 
With regard to the spent herrings, it may be noted that 13 females 
and 8 males belonged to the first series, and 24 females and 35 males to 
the second series. The two large females were spent and another at 
288mm. The grouping of the spent fish in ‘5em. is as follows :— 
OTs Dosh OS) hid ® "hob eb 96. sb, Oi a5) 28) Toe 20) 5) a0) snotao | meeneeee meen 
Males, 1 Pit) PRET SOR OR a eed Ve Si PVs" S52. FS Saar 
Females, - = Pah Dus Din dike, ai oe -peeelS) Or epee. Ob af P= = a eo ee ee 
1 ae anil ay Re ee ey fee ee Se ee heme SS 
8. CoNCLUSIONS. 
It is evident from the above account that the herring grows slowly, 
and that those authors who supposed that it might reach the mature 
condition in a year or eighteen months were very wide of the mark. 
At the end of the year in which it was born, that is to say, in 
December, the spring herring rarely exceeds 50mm. (2 inches), and the 
great majority are much smaller; at the same period, the autumn 
herring may be as small as 14mm. (a little over 3 an inch), and is rarely 
over 12 inches, or 35mm. This difference between the spring and 
autumn herring, it may be said, persists throughout. There is nothing 
to indicate that the rate of growth is greater in one than in the other, 
an interval of about 1:5em.-2em., or a little more, separating the mean 
sizes of the two classes at the same date. This is what might be 
expected, since an interval of five or six months intervenes between the 
spawning periods, and the difference in size between the spring and 
autumn herrings thus represents about half the amount of the growth 
in a year. 
While both autumn and spring herrings are included in the collec- 
tions with which T have dealt in this paper, those of the latter are the 
most complete; and I have set forth on the accompanying table the 
particulars regarding a number of the collections in order to show, in 
collective fashion, the rate of growth and the age at different sizes. 
Though these collections belong to different years and to various 
localities (but all on the east coast of Scotland), it will be seen that 
there is a very considerable uniformity of results. 
The monthly rate and the annual rate of growth, it may be said, are 
calculated from a larger number of decimals than the rate per day, and 
the age is computed from the middle of March. It will be observed 
that the erowth in the summer months is much more rapid than in the 
colder part of the year; and the mean annual rate of growth in the 
four best cases, where the period is long and the numbers of herrings 
considerable, is 45°-4mm., or about 1? inches. If the rate between 
January and May is included (49°6) the mean rate is 44°6mm. 
| TABLE. 
