THE SUMMIT OF THE YEARS 



sand or sawdust or straw of his cage, if no water is 

 handy. I should like to know why he is fond of shell- 

 fish, and how he secures them, since he is in no sense 

 an aquatic animal. In the laboratory you may 

 easily learn how a mink or a weasel kills a chicken 

 or a rat; but how does it capture a rabbit by fair 

 running in the woods or fields, since the rabbit is 

 so much more fleet of foot? In the laboratory you 

 might see a black snake capture a frog or a mouse; 

 but how does it capture the wild bird or the red 

 squirrel in the woods? It is this interplay of wild liEe, 

 the relations of one animal with another, and how 

 each species meets and solves its own life prob- 

 lems, that interest us, and afford us the real key to 

 animal behavior. I fancy the keeper of the Zoo can 

 really learn very little about his animals that is 

 valuable and interesting. Or what does the public 

 get out of its Sunday or holiday visits to a zoological 

 park, besides a little idle amusement? The beasts 

 there are all prisoners; and they are more dejected 

 and abnormal than human prisoners would be under 

 like conditions, because they are more completely cut 

 off from their natural surroundings. 



With very low forms of animal life the case is dif- 

 ferent. They are affected very little, if at all, by the 

 presence of man and by artificial conditions. Pro- 

 fessor Loeb's experiments with the medusae, ascidi- 

 ans, worms, and moUusks established many things 

 about these low forms well worth knowing, — and 

 168 



