34 , WALTER S. HUNTER 



Although the nature of the learning process is not our spe- 

 cific problem, the differences in the total number of trials re- 

 quired for learning by Bob and the last two animals are so 

 great as to invite comment. The conditions under which the 

 records were obtained differ in the following points: (i) Jack 

 and Jill were younger than Bob by at least a year. (2) Work 

 was begun with them in July and with Bob in (the preceding) 

 October. This brought him nearer the period of hibernation 

 when his appetite would begin to fail. (3) Jack and Jill received 

 more trials daily and also were tested for more days. Con- 

 sidering the fact that when the experiments ceased Jack and 

 Jill were younger than the other two raccoons were when the 

 latter started and yet had accomplished as much, I do not 

 believe that age was an important factor in determining the 

 reactions. However, the actual fact of an age difference re- 

 mains. The second point should have little explanatory force, 

 since the animals were always eager to work. As to the third 

 point, one would expect this factor to work in a direction oppo- 

 site to that which the results indicate. However, such was not 

 true with the rats, and it may be that here also the lesser num- 

 ber of trials daily is more favorable to rapid learning. The fact 

 of a possible difference of preference for light and dark remains 

 to be considered. Of the first 50 trials. Bob made 56% correct. 

 Of the first 45 trials, Jill made 22% correct. Jack made 48% 

 successful responses out of the first 45 trials. Age differences, 

 differences of brightness preference and differences in the num- 

 ber of daily trials are possible explanations for the varying 

 lengths of the learning records. Innate (?) individual abiUties 

 must also be recognized. (Betty's results are not considered 

 because of their unreliability at this point of the experiments.) 



Summary. — The only comparative statement with reference 

 to the learning periods of the different groups of animals 

 that the facts warrant is this: The raccoons Jack and Jill and 

 both dogs belong together in the class that learned most slowly. 

 The second class with reference to speed of learning is com- 

 posed of the rats. Bob is in a class by himself. He learned 

 more rapidly than any of the other animals. Further comments 

 upon this aspect of the learning process will be deferred to the 

 section on children. 



