GENETIC TYPE AND THE ENDOCRINES 537 



The adjustment of the animal to the negative signal would, 

 of course, require that it remain inactive during the sounding. 

 This behavior is represented graphically as follows: 



Cl. 120 Food Cl. 120 Food 



Cond. St. Rotation of disk Cond. St. Rotation of disk 



| Inactivity Cl. 50 | Inactivity 



From four to six conditioning signals were given simul- 

 taneously with food every day. One signal of 30 seconds 

 duration was applied to determine the value of the response 

 for that period, and this value was measured in hundredths 

 cubic centimeters by the manometer. It was found that as 

 a general rule the response to the second signal of the day 

 was the most vigorous, and this response therefore deter- 

 mined the value of the reaction. This procedure was varied 

 from time to time so that the dog would not become accus- 

 tomed to the order of the test signal. A typical daily pro- 

 cedure is shown in the record for animal 740 $ , an English 

 bnlldog-bassethound F l5 dated May 3, 1933 (table 5). 



TABLE 5 

 Dog 740 <$ 



STIMULUS DURATION LATENT PERIOD VALUE OF RESPONSE 



75 cl. 120 3 sec. reinforced with food 



76 cl. 120 30 sec. 6 sec. 4 reinforced with food 



77 cl. 120 3 sec. reinforced with food 



18 cl. 50 30 sec. not reinforced 



78 cl. 120 3 sec. reinforced with food 



In this dog the only reactions of interest from the point 

 of view of the conditioned salivary performance are the second 

 and fourth, the former to the positive signal, and the latter 

 to the negative. The response to the short signals are, of 

 course, zero, since the salivary reaction did not have time 

 to begin before food was presented. The experiments usually 

 ended with a positive signal. 



When the experiments were started it was thought that 

 the value of the conditioned salivary reaction alone could be 

 used as the criterion for behavioral type. Many difficulties 



