726 



ARTHUR J. RIOPELLE 



Fig. 4. Cynomolgus monkey 

 to the head. 



[M. irus) during edematous phase following 2,000 



avoidance task on which they had been given extensive preirradiation train- 

 ing. They had to jump over a low barrier within 4 sec after the onset of a 

 Hght to avoid shock. Tests were conducted on normal animals and on those 

 drugged with reserpine. No deficit could be detected in the results, nor was 

 there altered sensitivity to reserpine, as had been re]X)rted by Ross et al. 

 (1954) for pentobarbital. 



Post irradiation discrimination training was begun between 2 and 3J/2 

 months after treatment. By this time, we could be sure of vision unimpeded 

 by swollen eyelids. The monkeys were given one visual discrimination prob- 

 lem (Fig. 1) every day for 25 days. The stimuli differed in form, color, and 

 size. 



The controls significantly surpassed the irradiated animals on this test. The 

 controls averaged 97% on the last six trials of the problem; the x-irradiates, 

 93%; and the gamma irradiates, 85%. 



Two of the x-irradiated and one of the gamma-irradiated monkeys lived 



