xviii 



Fourth Annual Report of the 



Varieties of herring in all degrees of ripeness up to maturity; (3) small herring 

 theHemng. ^j^ig]^ j^^ve Spawned — small 'spent' herring. Hitherto the size 

 of the fish, rather than the sexual condition, has apparently deter- 

 mined whether the term ' matie ' should be applied. In the same 

 districts, and even in the same shoals, large sexually immature 

 herrings are often found along with small ripe or nearly ripe her- 

 ring, hence herring appear not only to vary in size in their fully 

 adult condition but also to vary in the size at which they reach 

 sexual maturity. It is pointed out that these results, as well as the 

 fact that the undivided ova vary in size in ratio to the size of the 

 fish, are likely to cause considerable variation in the progeny, which 

 result from the interbreeding of fish of varying size and age. Of 

 the fish caught in the early part of the season a much larger 

 proportion are immature and small, and probably also younger 

 than is the case later on. The adult fish appear to reach a more 

 advanced stage of ripeness before they approach the spawning banks. 



From the measurements made it is shown that the length of 

 the head varies considerably, the extremes being found in herrings, 

 of all localities and both seasons, the percentage with the larger 

 size of head being rather greater among the winter than the 

 summer herring ; but this difference, like that of the total length, is 

 considered insufficient to prove a racial distinction. 



The position of the centre of the dorsal fin, in a majority of the 

 winter herrings, is anterior to the centre of the body, whereas 

 among the summer herrings a large percentage have it behind the 

 centre. In the immature fish, however, the fin centre is generally 

 anterior to the body centre. 



The anal and pelvic fins show a corresponding difference in 

 position. As regards the pelvic fin, however, this condition is limited 

 to the adult and larger young herring, the pelvic fin being found, 

 like that of the sprat, anterior to the dorsal fin in young herring 

 below 60 mm. in length. 



The pectoral fin varies very slightly in its relative position on 

 the winter and summer herring. 



The relative basal length of both the dorsal and anal fins 

 conveys no indication of racial distinction between the summer 

 and winter fish. The dorsal fin is in all the herrings generally 

 longer than the anal, only about IJ per cent, of the summer 

 herrings and 7^ of the winter having the anal fin longer than the 

 dorsal. Further details are given respecting the number of fin 

 rays, keeled scales, circumstances of spawning, &c., but which 

 scarcely affect the question of racial distinction. The inquiry, so 

 far as it has gone, tends to prove that there is no racial distinction 

 between the herrings found in the various localities around the 

 Scottish coast. Judging, however, from the more backward posi- 

 tion of the dorsal pelvic and anal fins, the doubtfully smaller head, 

 and the slightly lesser size of the summer herrings, more minute 

 inquiries may indicate a slight difference between the winter and 

 summer herrings. 



The Board have already expressed regret that so many tons of 

 sprats are annually used as manure. Were it possible to transmit 

 sprats at a reasonable rate to the large centres of population, they 

 might form an exceedingly cheap and valuable addition to the 



