APPENDIX. 311 



it belonged to another fish. The flesh is white, or of a dirty 

 yellow ; tasteless and unhealthy. When hooked by the angler 

 under these circumstances, they are quite passive and helpless, 

 and suffer themselves to be dragged almost unresistingly to the 

 shore. In early spring they fall down the rivers, and, like other 

 valetudinarians, repair to the sea for the recovery of their 

 health. 



From the peculiar structure of their single heart, the circula- 

 tion of the blood in most fishes is weak and venous, and without 

 the arterial vigour of terrestrial animals. Under certain circum- 

 stances, salmon will permit their body to be felt all over with 

 the hand, and even appear to derive some gratification from 

 gentle friction. I have repeatedly endeavoured to ascertain if there 

 was any beating of the heart or pulse in any part of the body, but 

 never could discover the least pulsation anywhere. Authorities 

 state, notwithstanding, that the heart of a large carp beats thirty- 

 six times in a minute. The salmon, being a larger fish, has pro- 

 bably a slower circulation, if we may judge from analogy with 

 respect to the mammalia. Man's heart contracts seventy-two 

 times in a minute a horse's thirty-six, and an elephant's (as I 

 have myself ascertained) only twenty-four times. The respira- 

 tion of fishes is, I believe, quicker than is generally supposed. 

 From a mean of many observations made on seven salmon of 

 different sizes, in a reservoir fed by a copious stream, I found 

 that they breathe fifty-four times in a minute. Man's respiration 

 is twenty. 



There is a peculiarity in the instincts of salmon worthy of 

 notice, viz. ; their almost invariable habit of returning from un- 

 known distances and depths of ocean to the 'streams where they 

 were bred. They may be forced by stress of weather, or the 

 pursuit of some of their natural enemies, into the mouth of a 

 strange river like a ship driven by a storm into a hostile port 

 but the vast majority find their way back to their native waters. 



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