554 W. T. JAMES 



after they are familiar with the trainer can the leash be 

 employed or any effort made to handle them. When the leash 

 is first used, the dogs struggle violently to release them- 

 selves. They jump, pull, bite, and whine as if in intense pain, 

 and tremble and withdraw when touched. This intense syn- 

 drome is characterized by dilated pupils, rapid breathing, 

 and accelerated heart beat. If the animals have recently 

 been fed, the food is regurgitated. The extremes of the group 

 require as much as 30 days' training before they will accept 

 the leash without hesitation, and even then they must first 

 be cornered in the run. When first taken to the laboratory 

 it is necessary to force them into the room and on to the 

 platform. The animals object to the harness and recording- 

 apparatus, and occasionally make hysterical efforts to release 

 themselves. After a few days there is no longer any struggle, 

 but the dogs refuse food until they have been starved for 

 at least 2 or 3 days. It seems that they object to any attempt 

 to fit them into a definite procedure. 



A long pre-training period is necessary with the dogs of 

 group B before the conditioning signal can be applied. This 

 is shown in text-figure 86. An eager interest in the location 

 of the sound is apparent when the signal is first introduced. 

 Note the head movements of one of this group in text-figure 

 87, figure 2. A variety of orientation and investigatory re- 

 actions occurs, including head movements and bodily postures, 

 and these continue until the animal is thoroughly familiar 

 with the stimulus. At first the dog refuses food presented 

 with the signal, but when once the food is accepted, a con- 

 ditioned orientation to the pan soon appears. The number 

 of applications of the signal before the development of the 

 conditioned salivary response does not differ greatly from 

 that found for the dogs of group A (text-fig. 88). When the 

 signal begins, the dog moves the head over the pan quickly, 

 and continues to move it back and forth as long as the signal 

 sounds. This is illustrated in text-figure 93 (fig. 3) showing 

 the typical reaction of one of the dogs of group B to the 

 conditioning signal. At times these animals cock the head 



