392 



F. 'M. Rolfs 



Fig. 66. — Burbanh plum leaves inoculated with pure cultures of Bacterium Pruni. The growth from a 

 seven-day s-oU-slant Hiss-glucose culture was thoroughly mixed in one hundred cubic centimeters of sterile 

 water and applied to the leaves by dipping the fingers into the water and then gently rubbing the leaves 

 between thumb and fingers. Inoculations were made on June 27, 1912, and the photograph was made on 

 August 27 , 1912 



a. Inoculated with a pure culture obtained from an apricot tuig 



b. Inoculated with a pure culture obtained from a nectarine twig 



c. Check. Sterile water was applied to the leaves 



d. Inoculated with a pure culture obtained from a peach twig 



e. Inoculated with a pure culture obtained from a plum, twig 



