DETERMINING BIOLOGICAL ACTIVITIES OF BACTERIA 171 



animal should be clipped and the skin disinfected with carbolic acid 

 or alcohol. 



Subcutaneous inoculations are most conveniently made in the abdom- 



FIG. 51. INTRAPERITONEAL INOCULATION OF GUINEA-PIG. 



FIG 52. GUINEA-PIG CAGE, 



inal wall, where the skin is thin. After clipping and sterilizing, the 

 skin is raised between the fingers of the left hand and the needle plunged 



