1. A bipolar bacillus was isolated from saliva and nasal discharge, and the internal organs of the cattle affected with influenza. 2. This organism was highly virulent for mice, guinea-pigs, rabbits, sheep, and cattle. 3. In the blood of the cattle affected with influenza were demonstrated anti-bodies specific for this organism. 4. The serum from the animals hyperimmunized against this organism has a curative power for this disease.
