PLATE 10£ 



1 and _ Characteristic postures of the English bulldog under laboratory conditions. In 



figure 1 the head is turned away from the pan during the negative signal; in figure 2 the 

 animal holds the head over the pan during the positive signal and growls in anticipation of 

 food as the conditioning signal continues. 



3 Attitude assumed by a bassethound-Engiish bulldog F l of the mid-group during the 

 signal for food. 



4 Boston terrier orienting to the food pan during the signal for food. These dogs are 

 relatively excitable but give a small conditioned salivary reaction to the signal. 



5 and 6 Two types of bassethound-Engiish bulldog F 2 s. The animal in figure o is an 

 extremely short legged hound type belonging to the mid-group; the animal in figure 6 is 

 long legged, with characteristic bulldog head. This animal made adjustment to the laboratory 

 but did not form a conditioned salivary response. Such dogs have variable behavioral 

 tendencies. 



617 



