256 Studies in Animal Behavior 



and teeth, and then reached in and got the nut, hold- 

 ing the jar upright with her feet. The next trial 

 resulted in practically the same way. The cap of 

 the jar was then screwed -on farther. Lizzie at- 

 tacked the jar industriously and finally removed the 

 cover, although working quite unsystematically. The 

 cover was put on as before and Lizzie worked at 

 it about fifteen minutes, getting more and more ex- 

 cited and impatient over her lack of success; some- 

 times she tried to bite through the glass at the lower 

 edge. After turning the cover this way and that 

 she finally unscrewed it and got the nut. After 

 numerous trials Lizzie never learned to unscrew the 

 cover by turning it around uniformly in one direc- 

 tion. She simply worked it back and forth until it 

 happened to become entirely unscrewed. 



Lizzie was then set to the task of getting food 

 out of a small box. Two sides of the box were 

 made of strong wire netting; the rest was wood. In 

 one corner was a small door which could be fas- 

 tened by a hook passing through a small screw eye. 

 In the first experiments a piece of apple was placed 

 in the box and the door, which stuck rather tightly, 

 was left unhooked. Lizzie looked at me while I 

 put the food through the door and she opened the 

 door at once and got the food. She did the same 

 at the second trial, after which, when the food was 

 replaced, the box was turned so as to lie on an- 

 other side. This seemed to disconcert Lizzie and 

 she tried biting and clawing at the wire netting, and 



