22 



Part III. — Twenty-seventh Annual Report 



none, a trace ; 1 S. Spr. d, 22 cm. : fat, none. The sample consists of two 

 classes of fish — one thin, the other class thicker in the body ; i.e., some of 

 the spents have recovered to some extent. 



Clyde.— Loch Fyne, Kilmichael Beg, 23rd April 1906 :— 304 Imm, 14 

 to 23 cm. : eggs, '05--15 mm.: o, 1*5-5 mm.: t, 1-4 mm.: fat, some; 

 2 Imm. dev., 21, 22 cm. : eggs, 25 mm. : t, 5 mm. : fat, some ; 1 W. Spr. 

 F. $, 22 cm. : eggs, 1-4 mm. ; 2 S. Spr. 6, 21, 22 cm. : t, 9, 10 mm. : fat, 

 some; 127 W. Spt., 19 to 26 cm.: eggs, *05-'15 mm.: o, 4-6 mm.: t, 

 4-7 mm. : fat, some. The stomachs contained copepocls, and in some cases 

 schizopods ; only a few were empty. This sample of herrings was captured 

 by Dr. Fulton. 



East Coast.— Anstruther, 7th April 1905 :— 24 W. Spr. F., 21 to 

 27 cm. ; 2 W. Spt., 23, 30 cm. : eggs, -15 mm. 



East Coast.— Aberdeen, 115 miles E.S.E. of, 24th April 1908:— 5 Imm., 

 23 cm. : o, 1, 4 mm. : t, 3*5 mm. : fat, large quantity ; 154 S. Spr., 21 to 

 27 cm. : eggs, '2-35 mm. : o, 3-7*5 mm. : t, 3-9 mm. : fat, from a large 

 quantity to none — as a rule, very little, or none; 12 W. Spt., 21 to 

 26 cm. : eggs, "2 mm : o, 4, and flabby condition : t, 5*5, and " skin " 

 condition : fat, little or none. The stomachs were empty. 



Summary. 



' Immature. — 14-24 cm. : eggs, *05-'25 mm. : o, 1-5 mm. : t, 1-4 mm. : 

 fat, some, great quantity. (See Analysis given below.) 



Imm. dev.— L8, 21, 22 cm. : eggs, -25 mm. ; t, 5 mm. : fat, some. 



S. Spr. — 17-27 cm. : eggs, -2-'35 mm. : o, 3-75 mm. : t, 3-10 mm. : 

 fat, as a rule a little, but also large quantity, and none. (See Analysis 

 given below.) 



W. Spr. F.— 20-27 cm. : eggs, 1*4 mm. 



W. Spt. — 19-30 cm. : eggs, -05--2 mm. : o, 4-15 mm. : t, 3-14 mm. : 

 fat, none, some. 



The herrings (immature, summer spawners, and winter spents) 

 examined during this month are characterised by having a small amount of 

 abdominal fat. 



The immature herrings were got in Kilmichael Beg, while the summer 

 spawners were obtained in the North Sea. On reference to the table it 

 will be seen that the immature herrings measured from 14 to 24 cm. in 

 length. These I regard as winter-spawning herrings, which will spawn for 

 the first time in the following winter. The winter spawners of the past 

 winter are represented by the spents measuring from 19-30 cm. This lot 

 contains the first spawning group. In Kilmichael Beg the winter spents 

 measured from 19 to 26 cm. There is therefore a year's difference in age 

 between the immature and the winter spents. The summer spawners 

 measure from 17 to 27 cm. They will probably spawn for the first time 

 within three or four months. In age they come about midway between 

 the immature and winter spents. Taking the age of the winter- spawning 

 herring from February, I regard the immature herrings as being fourteen 

 months old, the winter spents as two years and two months, while the 

 summer spawners, counting from the month of August, are twenty months 

 old (videp. 57). Now in the matter of the abdominal fat, the immature and 

 summer spawners are little better than the winter spents. The immature are 

 beginning to store up fat ; some have already a large quantity, but most 

 have little. The winter spents show a similar condition. During the 

 summer the winter spents and immatures will store up much fat and 

 become " matjes " — that is, very fat herrings having small reproductive 

 organs which are about to ripen. The herrings have probably been 

 growing since the winter. The summer spawning herrings will not lay up 



