692 



O. D. ANDERSON 



2 the three photographs show the postures of the same dog 

 after 5 weeks of daily administration of 2 gms. of thyroid 

 extract. The first of these (left) illustrates the typically 

 alert pose of the animal just before the stimulation was 

 applied, the next shows the posture at the moment the metro- 

 nome began, and the last shows the reaction during the 

 course of the stimulation. Below these, a graphic record of 

 the behavior during this phase shows (from top line down) 



EFFECT OF THYROID EXTRACT OH THE CONDITIONED SALIVARY 

 REFLEX m ATHVROIDECTOMIZED DOG 



1 



.Dec 



Text-figure 124. Chart showing the effect of thyroid extract on the conditioned 

 salivary reflex in the thyroidectomized dog (1030). Note the increase in the 

 values of the reflex when the amount of extract administered Avas doubled. 



the quick movement of the head at the beginning of stimula- 

 tion, the movement of the body as the dog gets to his feet, 

 the alteration in respiration and the ready flow of saliva 

 beginning almost immediately after the metronome began to 

 click. 



In text-figure 124 the influences of two periods of thyroid 

 administration on the C-R are shown. In the first period, 

 a stable and fairly strong response was maintained with 1 gm. 

 daily, but, as is shown, it disappeared completely 12 days 

 after discontinuing the treatment. Two months later the ex- 



