574 W. T. JAMES 



example, when the dog is frightened or hurt. This type would 

 correspond more to the English bulldog, which is described 

 in detail below, but which is a highly mixed behavioral type. 

 This dog is quiet and restrained under ordinary conditions, 

 but once a painful irritation is employed to elicit an avoiding 

 reaction, intense excitement occurs. The animal has charac- 

 teristics of both polar groups, yet it has characteristics not 

 found in any other animal. 



The term choleric would seem to refer to what we have 

 called the B-minus group. These dogs are active and have 

 difficulty in forming stable negative reactions. 



Due to the complexity of the behavioral patterns of the 

 dogs, and the differences found among them, it is best at 

 present not to attempt to give them specific temperament 

 designations. Each type should be studied in more variable 

 controlled situations, and we should have a better under- 

 standing of their physiological processes before attempting 

 to name the temperaments. The above terms may fit many 

 of the dogs, but it seems that there are so many types and 

 variations among dogs that a more diversified and finer dif- 

 ferentiating method should be found. This will not come, 

 however, until we have a better understanding of the types 

 and the nervous disturbances each develops under difficult 

 and restrained conditions. 



It should be emphasized that the present experiments in- 

 volved a wider variety of dogs than the experiments of 

 Pavlov. This was necessary because of the difference in the 

 object of the experiments. Pavlov was interested in deter- 

 mining the nature of the conditioned salivary response and 

 something of the laws governing its action. For this reason 

 animals were selected which would be of a more adjustable 

 type. In the present experiments, a large group of different 

 dogs was used in order to determine something of the varia- 

 bility of behavior among them, beginning of course with 

 certain pure breeds which under kennel conditions were un- 

 doubtedly widely different in behavior. It may be due to the 

 difference in materials studied that we have such difficulty 



