A. Section of normal cerebellum of a dog. B. Section of cerebellum of a dog after 

 injection of diphtheria toxin. C. Section of cerebellum of a dog after injection of 

 diphtheria toxin plus morphin. D. Section of cerebellum of a dog after injection of 

 diphtheria toxin and the continuous administration of nitrous oxid for four hours. 



FIG. 74. PROTECTIVE EFFECT OF MOBPHIN AND OF NITHOUS OXID ox THE BRAIN- 

 CELLS OF DOGS WHICH HAD RECEIVED INJECTION OF DIPHTHERIA TOXIN. 



Compare the Purkinje cells in C and D with the disintegrated hypochromatic cells in 

 B. (From photomicrographs, X 310.) 



