246 RATE OF GROWTH OF SOME SEA FISHES. 



November must have been either from two to five months old, 

 having been hatched in the summer of the same year, or from 

 fourteen to seventeen months old^ having been hatched in the 

 summer of the previous year. It is obvious that the pilchard could 

 not reach a length of 13 cm. in two months, and we have observa- 

 tions on the growth of the young herring, and on the Mediterranean 

 sardine at Marseilles, which show that it could not grow to such a 

 size even in five or six months. Marion's conclusions concerning 

 the sardine at Marseilles are quoted in my paper on the pilchard in 

 the previous number of this Journal ; he estimates the length 

 of the year-old fish at 14 cm. I see no reason to suppose that the 

 pilchard at Plymouth grows twice as fast as the sardine at Marseilles. 

 Meyer, after a series of very careful and successful observations, 

 found that the herring in the Baltic at five months old was 6 "5 cm. 

 to 7" 2 cm. long, and we have no reason to think that the pilchard 

 grows twice as fast as the herring. It is nearly certain, therefore, 

 that the pilchards taken at Plymouth in November and measuring 

 13 to 165 cm. in length, were a little more than a year old, being 

 derived from the spawn of the preceding year. But if this be so, 

 where were the young pilchards derived from the spawn shed in the 

 previous summer of the same year ? 



I had not seen any very young pilchards, that is specimens less 

 than 13 cm. long, since July last when I took the stages described 

 in the previous number of this Journal, At the end of October I 

 was at Mevagissey and discussed the pilchard question with Mr. 

 Dunn. He told me that young pilchards only 2 to 3 inches long 

 were always on the coast between September and Christmas, and 

 that he knew this because he found them at that period in the 

 whitings' stomachs. He gave me several specimens measuring 5 to 

 8 cm. in length which he said were taken some years ago in a 

 mackerel seine in September. At Plymouth in November I opened 

 the stomachs of many whiting but found no young pilchards in 

 them. But on opening the stomachs of some mackerel I found 

 the kind of fish for which I was searching. On November 5th 

 I opened twelve mackerel, 10 to ! 1 inches long, bought on the fish- 

 quay ; in one of these were two pilchards 6 and 8'5 cm. long which 

 were sufficiently intact to be identified with certainty ; in another was 

 a pilchard 9 cm. long, while in two others were half-digested fish which 

 were probably also young pilchards of similar size. On November 6th 

 I opened thirty-three mackerel, in seven of which there was food m 

 the stomach, in each case consisting of one or two more or less digested 

 fish 5 to 7 cm. long, apparently pilchards. In one of these mackerel 

 there were remnants of several fish in the condition of poutines nueSy 

 and these were certainly clupeoids and probably pilchards. 



