316 PEOSE HALIEUTICS. 



rapidly for some years,* but afterwards more slowly j 

 at two years old, they weigh six pounds ; for the next 

 three years, the aggregate increase of weight in the 

 same fish is on an average perhaps not more than three 

 and a half to four pounds, and later it is stiU less, so 

 that those great Swedish salmon which, like Swedish 

 turnips, are remarkable for size, and reach not unfre- 

 quently a hundredweight, are most probably of very great 

 age indeed. We come now to the 



Clupid^, ob. Herring Tribe. 



To this important family the ancient world was be- 

 holden for large supplies of excellent food, though not to 

 the same extent as we are. Our herring, C. harengus, for 

 instance, was totally unknown to them in any form ; 

 alive, it was an utter stranger to the waters of the Me- 

 diterranean, and the art of curing being of comparatively 

 recent date, we may be sure that none of those galleys 

 which bore Colchester oysters to Baise, and live scari 



* ExperimentB have been frequently made to ascertain tlie 

 food most fattening for this and other members of the tribe Sal- 

 monidse ; and the results obtained have been, as might be antici- 

 pated from what is observed in our own. race, extremely variable 

 and uncertain : one thing clearly established is that even in health, 

 with fishes as with man, it is impossible to infer what the amount 

 of assimilation wiU be from the bulk of aliment received into the 

 stomach ; another inference is that light food afibrds more nou- 

 rishment than heavy. Thus of three batches of the common 

 trout, S. fario, fed differently on worms, minnows, and dark-co- 

 loxired flies found on the surface of the water, those fed on the 

 worms grew very slowly, and remained poor and lean; those 

 brought up on minnows throve and grew apace ; but those in- 

 dulged with a copious supply of flies plumped out fastest, and 

 were found to outweigh both the others put together ; though it 

 was ascertained that the whole mass of these muscse did not equal 

 by a great deal the weight of either worms or minnows. 



