84 AMERICAN FISHES. 



marvellously allured, taking it greedily, at a very nhort distance from 

 the sea, we cannot determine. It is like nothing that has any existence 

 in nature ; and some persons have imagined that the Salmon is 

 deceived by the gay colors and the ripple of the water, and so takes 

 them for small fish. This is not credible, however ; and the most 

 plausible suggestion is that of Sir Humphrey Davy, that the fish, on 

 their return from salt water, where, of course, they find nothing 

 analogous to the natural or artificial fly, are actuated " by a sort of 

 imperfect recollection of their early food and habits ; for flies form a 

 great part of the food of the Salmon fry, which for a month or two 

 after they are hatched, feed like young Trouts — and in March and 

 April, the spring flies are their principal nourishment. In going back 

 to fresh water, they may perhaps have their habits of feeding 

 recalled to thein, and naturally search for their food at the surface." 



While I am on this topic, it may not be uninteresting to quote the 

 relation of an experiment tried with regard to the effect of various 

 kinds of food on the Trout, as it is probable that, in fish so closely 

 allied, the facts would not vary much in relation to the Salmon. 



Mr. Stoddart relates this, in his " Art of Angling as practised in 

 Scotland ;" but the experiment was made in the South of England. 

 " Fish were placed in three separate tanks ; one which was supplied 

 daily with "worms, another with live minnows, and the third with those 

 small dark-colored water flies, which are to be found moving about 

 on the surface, under banks and sheltered places. The Trout fed with 

 worms grew slowly, and had a lean appearance. Those nourished 

 on minnows, which, it was observed, they darted at with great 

 voracity, became much larger ; while such as were fattened upon 

 flies only, attained in a small time, prodigious dimensions, weighing 

 twice as much as both the others together ; although the quantity of 

 food swallowed by them was in no wise so great." 



I may here observe that, from the fact of the Salmon roe, when 

 preserved secundum artem^ proving a most deadly and infallible bait 

 for Salmon — so much so indeed, that the use of it in England is 

 regarded as unsportsmanlike, and as an act of poaching — there can 

 be little doubt that the ova of fishes of all kinds contribute to their 

 food, and add probably to the richness of their flesh. 



I have now gone through, I believe, all that is most remarkable and 



