Instinct and its Lessons 129 



all migratory fish those whose history we know best, 

 and though, to tell the truth, we know next to nothing 

 about them, it is yet quite evident that the fry not only 

 do not know their own parents, but keep sedulously 

 out of the way of every member of their kind which 

 is large enough to eat them ; for fish are sad cannibals, 

 and when there is question of a dinner the claims of 

 relationship are apt to be little regarded. The Smolts 

 go down to the sea in " schools " on their own account, 

 quite apart from the full-grown fish, waiting for a flood 

 to take them over obstacles which they have never 

 had an opportunity of observing. Should the water 

 remain too low for travelling, they are consumed with 

 a fever of restlessness, causing them continually to throw 

 themselves out of the water ; and if confined in a pond 

 they will, as already mentioned, throw themselves on 

 to the bank, in obedience to their irresistible yearning 

 to be off. In the case of a fish, therefore, the idea of 

 guidance is out of the question : to suggest it in con- 

 nexion with the Turtle, would partake of the ludicrous. 

 As we have seen, no Lemming ever makes the journey 

 twice, and none can therefore serve as a guide to the 

 company. 



Such are a few items out of the mass of evidence, 

 that the phenomena of instinct affords us in our in- 

 vestigation of nature. It is, I think, undeniable that 

 even assuming an instinctive principle to start with, 

 there are many difficulties in the way of the theory 

 which would trace all the forms of instinct now existent 

 to the perpetuation, through Natural Selection, of acci- 

 dental variations happening to be serviceable. It seems 

 impossible to conceive that means so nicely adjusted, 

 were elaborated by any power not having the end in 

 view which they so accurately attain ; in some cases 

 their transmission appears to be physically impossible; 

 in all which I have cited there seems to be conspicuous 

 absence of any medium whereby knowledge may be 

 imparted. 



Yet of these instincts each and all serve an end. 



