4722 Fishes. 



hunger they will swallow anything they meet with." This illustrious 

 man, for he truly was so, adopted other theories and hypotheses in 

 regard to the herring : he thought that all herrings were of one year's 

 growth, and that when they once abandoned the coasts they never 

 more returned to them ; and, lastly, he concluded that the small fishes 

 on which herrings feed (which, by-the-bye, he admits he could not 

 discover), besides being inconceivably small, " are used but sparingly 

 by the herring. 1 ' 



Hie Food of the Salmon. 



From about midsummer, but more especially with the autumnal 

 floods, salmon and sea trout of various sizes begin to rush up the 

 fresh water streams and rivers : their object in this annual migration 

 is clearly enough made out — they are proceeding to the place of their 

 birth, the original streams in which they first saw the light, there to 

 perform the act of the propagation of their species. As the roe and 

 milt grow the fish get more and more out of condition : from the time 

 it enters the fresh-water rivers it ceases to feed, properly speaking. 

 True, it may be tempted to spring at an artificial fly, or to attack a 

 w T orm or minnow, in accordance seemingly with its original habits and 

 nature ; for whilst it lived as a smolt in the fresh waters the ordinary 

 food of trout was also its food ; but from the time it first descends to 

 the ocean as a smolt and tastes its marine food, it never again resorts 

 to its infantile food as a constant mode of nourishment. This great 

 fact, well understood by fishermen and true anglers, Mr. Young, of 

 Invershin, has placed, by direct experiment, beyond all doubt. 



But what is the food of the true salmon in the ocean ? — that food 

 which he cannot do without ? — that food on which relatively all his 

 good qualities depend ? 



As nothing is ever to be found in the stomach and intestines of the 

 fresh-run salmon but a little reddish substance, I placed a microscope 

 over this substance. After much difficulty I came to the conclusion 

 that it was composed of the ova of some species of the Echinodermata. 

 With salmon, whilst in the sea, this is the constant and sole food : sea 

 trout and hirling also live on it, but they readily take to other food, 

 even in the sea, such as the sand-eel, herring-fry, &c. In fresh-water 

 streams the true salmon does not feed ; the sea trout feeds, but does 

 not thrive. The absence of this peculiar food forms an insurmountable 

 obstacle to the localization of the salmon, and even of some kinds of 

 the sea trout in fresh -water lakes. 



