Berry, Imitation in Cats. 3 



this bar a string passed up over the box and entered it at the mid- 

 dle of the end farthest from the door. To open the door it was 

 necessary for the cat to pull a knot at the end of the string. The 

 knot was close against the inside of the box (see Fig. i). 



Results. — By fastening a piece of meat to the knot I taught M 

 to open the door. At the end of the fourth day, the association 

 between the pulling of the knot and the opening of the door seemed 

 to be well formed. 



X, Y and Z were put into the box together. In less than five 

 minutes X was pulling the knot. With Z watching, X went to the 



knot, seized it and pulled hard enough to open the door. After 

 they had been fed and put into the box again, Z pulled the knot 

 first. X then tried it, and finally Y seized it and succeeded in 

 opening the door. When they were put back Z at once opened the 

 door by pulling the knot. Left in the box alone for ten minutes, 

 Z did not get out again. 



The following is Z's record for the next two days when in the 

 box alone. Z learned to get out in less time than it required to 

 teach M. 



Oct. 27 she got out, 

 1st time in 3' 

 2d time in i' 



Oct. 28, 



1st time in 2' 

 2d time in 30" 



