GENETIC TYPE AND THE ENDOCRINES 557 



behavioral chart (text-fig. 94). This is illustrated also in the 

 kymograph records of the reaction to the first negative in 

 text-figure 91 (fig. 4). The nervous setting in the dogs of 

 group B is more intense than for those of group A, and the 

 nervous reactions in group B are released more quickly. 

 Let us consider dog 438 9 in the experimental situation. The 

 nervous setting for the food reaction is shown by her orienta- 

 tion to the food pan during the intervals. When the positive 

 signal for food is applied, the dog quickly orients to the pan 

 and looks for food. If a test signal is given, the dog goes 

 through the same postural reactions, and, since food is de- 

 layed, there is a strong secretion of saliva during the sounding 

 of the 30 second signal. The head moves right and left over 

 the pan as though waiting for the food. Now the dog has 

 the same nervous set when the first negative signal is applied 

 as when the positive signal is given. Since the negative signal is 

 the same in sound as the positive, the reaction is released just 

 as quickly. As the experiments continue, the position of the 

 negative is varied from time to time. Thus the dog does not 

 develop a definite set for this signal but is always in a 

 nervous attitude for positive signals and food. For this reason 

 all initial reactions to both positive and negative signals are 

 the same. As the signals are contrasted repeatedly, however, 

 the dog seems to appreciate the difference between them; 

 but since the initial setting is not changed, there is always 

 some positive reaction. This is shown by the fact that as 

 the signal continues and the difference in frequency is ap- 

 preciated, the animal turns the head away from the pan until 

 the signal stops, a definite negative movement but one which 

 is superimposed on the first vigorous positive reaction. The 

 salivary or glandular reaction cannot be cut off sharply, as 

 can the neuromuscular actions, and there is, therefore, a 

 flow of saliva even during these negative postural movements 

 away from the pan. 



The difference between the dogs of groups A and B is, 

 then, one of nervous tension and setting for the specific 

 reaction rather than of differentiation between the two sig- 



