K. LISSAK AND E. ENDROCZI 



295 



be observed. How wide die variadons in the same species may be is 

 illustrated by the difference between the corticoid contents of the adrenal 

 venous blood in domesticateci and wild rats respectively. 



The corticoid spectrum of the blood in the adrenal vein is interesting 

 not only in its quantitative aspect but also because, under certain condi- 

 tions, the synthesis of such compounds may occur as will have an altered 

 effect on central nervous organization. Considering all these aspects we 



Fig. 2 

 Relationship between the inhibitory period ot" ahnientary conditioned reflex caused 

 by electric shock on the hind-leg and the corticoid content in the blood ot the 

 adrenal vein. Black columns: duration of inhibitory period in dogs. Blank columns: 

 proportion of hydrocortisone and corticosteronc. 



should like to deal with certain data concerning the endocrine background 

 of temporary connections or that of neuroses resulting from a break in 

 those connections. 



An alimentary conditioned reflex was established in dogs in the 

 following manner: on the sound of the positive bell the animal pushed a 

 swing-door to reach the food. Another bell sound served as negative 

 acoustic stimulus. After sixteen daily trials at three-minute intervals, the 



