570 W. T. JAMES 



At the beginning of the experimental procedure, the dogs 

 of group A are more excitable than under the usual condi- 

 tions of the kennel, but they readily become adjusted to the 

 laboratory and form conditioned postural and salivary reac- 

 tions. Following this initial adjustment, the total behavioral 

 pattern changes, and there is a gradual elimination of bodily 

 movements not absolutely essential for food taking. The ad- 

 justment is directed toward an economical performance, and 

 the animals soon cease to orient to the signals or even to 

 the food pan, but hold the head just beside the pan until 

 food is actually presented. In some instances during the 

 intervals between signals, the head rests on the board beside 

 the pan, and at times the animal may even go to sleep in 

 this position. The specific negative signal cannot be intro- 

 duced before the relationship between the positive signal and 

 food has been established. As soon as this point is reached, 

 the activity of the animal is gradually decreased. For this 

 reason there is little reaction to the negative. This inactive 

 stage is soon reached even though the negative is not intro- 

 duced ; thus it is not dependent on a specific negative signal. 

 Following the disappearance of the conditioned saliva and 

 bodily movements, most of the dogs refuse food under lab- 

 oratory conditions. The quiet environment of the laboratory 

 emphasizes their lethargic natures. It may be said that they 

 passively accept the situation and make no effort to modify 

 the procedure by their own actions. They never become im- 

 patient or try to leave the room, and after the first few 

 week's training it is not even necessary to use the restraining 

 harness. The dogs sit passively until food is presented, then 

 slowly approach the pan to eat. The total perceptual situa- 

 tion, involving food as the center, is quite different in these 

 dogs than it was found to be for the animals of group B. 

 For the dogs of A, the laboratory becomes primarily a place 

 in which food is obtained. If they are not hungry it is a 

 place to sit until the experimenter leads them out. There 

 is no definite urge on their part to leave if they are not 

 hungry, nor to react to other signals in an environment which 



