﻿Smithsonian 
  Report, 
  1943. 
  Weintraub 
  

  

  Plate 
  2 
  

  

  Demonstration 
  of 
  the 
  Growth-Inhibiting 
  Effect 
  of 
  Actinomycin. 
  

  

  The 
  substance, 
  applied 
  in 
  the 
  cross-shaped 
  groove, 
  diffuses 
  some 
  distance 
  into 
  the 
  agar 
  and 
  prevents 
  the 
  

   growth 
  of 
  gram-positive 
  bacteria 
  (2= 
  Bacillus 
  mycoides; 
  4 
  = 
  Sarcina 
  littea 
  ) 
  but 
  not 
  of 
  gram-negative 
  bacteria 
  

   (1 
  = 
  Escherichia 
  eoli; 
  3=Azotobacter 
  beijerincki). 
  (Courtesy 
  Waksman 
  and 
  Woodruff, 
  Journal 
  of 
  Bacteri- 
  

   ology, 
  August 
  1941.) 
  

  

  