DISCRIMINATIVE ABILITY OF THE TURTLE 9 



The above account is a very general one. Many variations oc- 

 curred in the behavior of turtles during the course of the experi- 

 ments. Different turtles would differ greatly in the methods by 

 which they seemed to attack the problem, and any individual 

 turtle might vary its course of procedure greatly from time to time. 

 Some of the more accomplished turtles would go through the 

 apparatus with machine-like precision, going straight for a box 

 when the slide was lifted and straight back again into the entrance 

 room after getting their reward or electric shock. But such 

 action was more characteristic of turtles that were nearing 

 perfection in any particular experiment. Such automaticity 

 probably resulted from several rather definite causes. The 

 individual had. become, through numerous trials, well accus- 

 tomed to travel and retravel a beaten path. As a rule its mis- 

 takes were few and its mental poise was not continually dis- 

 turbed by annoying shocks. The most tractable, possibly the 

 most " intelligent " turtles, showed greatest regularity of behavior 

 at this time. Seemingly nervous, erratic turtles, those which 

 appeared never to become entirely tame, showed lack of auto- 

 maticity. A direct return to the deeper water of the entrance 

 room by a turtle that has succeeded in securing the bait is a 

 natural action, since Chrysemys appears unable, or at least 

 unwilling, to tear up and swallow its food unless its mouth is 

 beneath the water. 



Unfortunately for the patience of the operator many of the 

 turtles, particularly during the earlier tests of an experiment, 

 were prone to hesitate and wander around in both the entrance 

 room and the runway. Or an individual might leave the entrance 

 room and remain quietly in the runway before the boxes for 

 some time, seemingly deliberating before making a choice. 

 That this was not always mental deliberation upon the par- 

 ticular problem in hand the writer is fairly convinced, for the 

 result of such hesitation was about as likely to be disaster 

 as gain. 



Turtles upon receiving the electric shock were diversely 

 affected by it. After a few such experiences some were ren- 

 dered so nervous and wild that their withdrawal from experi- 

 mentation was necessary. Others were at first thus affected 

 but gradually became accustomed to the experience or reacted 

 favorably under lessened stimulus. Some were simply rendered 



