Abstract
1. The drying of fowl cholera attenuated, or killed by shaking, drying or heating proved to be of no value as vaccines.
2. The organism killed with disinfectants, fowl cholera aggressine and condensed broth culture of the organism, both mono- and polyvalent, gave better results; the production of an abscess at the site of inoculation was, however, a common defect of these vaccines.
3. Nucleoproteids, both mono- and polyvalent, gave very satisfactory results, conferring a solid immunity to animals treated with no ill effects.
Finally I wish to express my best thanks to Prof. N. NITTA for his valuable suggestions in this work.
