302 



BACTERIAL DISEASES OF PLANTS 



were obtained. Time of day might make a difference. The old 

 and the very young leaves appear to be partially or wholly 

 immune (see observations under Nos. VIII and X). 



Fig. 232.— Spotted cauliflower head from Sanford, Florida, April 3, 1916. Gray 

 to black discoloration of the epidermis and deeper tissues of the inflorescence. 

 Plates were poured by Miss McCulloch on April 4 and Bacterium maculicolum 

 was obtained and used for successful inoculations. 



The period of incubation is short, numerous spots being 

 visible within 3 to 6 days from the time of spraying, and always 

 beginning, as in the spots on the naturally infected field cauli- 

 flowers, in the substomatic chamber. 



