THE SUMMIT OF THE YEARS 



look upon instinct as an inflexible, cast-iron rule 

 make a mistake. No live thing is entirely a machine ; 

 the vital forces certainly act in ways quite different 

 from the mechanical; and yet I am convinced that 

 the behavior of the lower orders is, for the most part, 

 automatic. 



The manlike apes undoubtedly show gleams of 

 what may fairly be called reason; and trained ele- 

 phants develop a wit that at least gives us pause. 

 One has to be careful how he ascribes reason even 

 to the highest of the lower animals, because there are 

 creatures which we look upon as much lower in the 

 scale of life that yet exhibit a degree of intelligence 

 apparently on a par with reason. 



For instance, take the case of the little hermit 

 crab. This creature has no shell of its own, so it takes 

 for its habitation the shell of some other sea-animal, 

 often that of the whelk. Upon this shell the sea- 

 anemone often grows, and reaps its advantage in 

 being moved about from place to place by the crab. 

 And the crab finds its advantage in the copartner- 

 ship, or what the biologists call the " symbiotic asso- 

 ciation," in the tentacles of the anemone which come 

 down near the head of the crab and seem to afford 

 it some measure of protection. If from any cause 

 the anemone be torn away from the shell, what hap- 

 pens? Now here is where the great reasoning powers 

 of the hermit come in; it hunts about seeking an- 

 other anemone, and when it finds it growing upon 

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