EATE or GROWTH OF SOME SEA FISHES. 241 



Fishing Boats, and Day^s History of British and Irish Fishes, is 

 that the herring spawns at Ramsgate in October and November. I 

 can, therefore, only assume the correctness of Meyer's conclusions 

 as to the rate of growth, and from the size of the herring fry 

 measured by Ewart and Matthews, calculate the period at which 

 the spawning occurred from which they were derived. 



The larval herring occurring in June wei'e about two months 

 old, some more and some less. This shows that the spawning took 

 place most abundantly in April, while the larval forms taken in 

 May and July must have come from spawn deposited in March and 

 May. Thus all the eggs shed in March and April had become 

 scaled young herrings over 2 inches long in July, constituting 

 60 per cent, of the catch of the stow-nets, while the 15 per cent. 

 larval forms taken with them came from the last eggs of the season 

 deposited in May. In August no larval forms still unmetamorphosed 

 were left, all the young herrings had undergone their transforma- 

 tion from the naked transparent larval condition to the scaled 

 silvery little fish similar to the adult herring except in size. 



There must be then a spring spawning of herrings somewhere 

 near the mouth of the Thames, taking place in March, April, and 

 May. The larger young herring taken in March and April are 

 probably derived from the autumn spawning which takes place off 

 Ramsgate in October and November. Now if we take October as 

 the principal month of the autumn spawning, it is just six months 

 from that month to April, the principal month of the spring spawn- 

 ing, which is a confirmation of the conclusions we have drawn as 

 to the occurrence of the latter. It is surprising that no direct 

 observations have ever been made on this spring spawning of 

 herrings at the mouth of the Thames. 



Clupea sjprattus, the Sprat. 



The character of the spawn of the sprat, and the period at which 

 spawning takes place, have been determined in several localities by 

 direct observation, and there are also a certain number of observa- 

 tions on record from which we may draw some conclusions as to the 

 rate of growth of the species. 



The paper on Whitebait, by Messrs. Ewart and Matthews, so 

 largely used in the previous discussion of the growth of the herring, 

 also supplies valuable observations on young sprats ; 2600 specimens 

 of whitebait procured from the Firth of Forth, between Alloa and 

 Kincardine, in December, January, and February, consisted almost 

 entirely (99i per cent.) of young sprats measuring If to 2| inches 

 in length. The authors themselves point out that in a previous 



