48 SPECIES OF THE SALMON. 



this has never been done ; therefore, there is no evi- 

 dence of the truth of the assertion. But even if 

 it be true, it is not to be wondered at ; because it 

 cannot be expected but that a fish, shut up in a fish- 

 lock, deprived of necessary food, and natural li- 

 berty, should fret, pine, and fall short of its natural 

 growth. 



These circumstances do not appear to me to weigh 

 much against what is placed in the opposite scale. 



As to the salmo trutta or sea- trout, this fish has 

 certainly always been considered as a separate spe- 

 cies. Authors of the highest authority so treat it, 

 and give a description of the fish different from 

 that of the salmon ; but I have several times ex- 

 amined the two, side by side, with the greatest 

 nicety and attention, and have not been able 

 to discover the slightest distinction in any external 

 character. I think indeed, I would defy any man 

 living to do it. The description given of it exactly 

 corresponds with the description of the salmon. The 

 spots, lateral lines, the sides, the belly, the tail, par- 

 ticularly, which is represented to be broader than 

 that of the salmon, is not so. The fins and the rays 

 are uniform ; and in addition to what Pennant says, 

 both fish have quadruple branchia ; in fact, the fish 

 were exactly alike in every particular. I have com- 

 pared a great many at different times. It does not ap- 

 pear that Mr. Pennant formed his opinion on any 

 experiment, but merely by observation on a single 

 fish. Suppose a man were to do this on the larva of a 

 butterfly, and did not by experiment substantiate the 



