The results obtained in this study may be briefly summarized:
1. Acid-resisting bacilli are found in many of the lower animals, more especially the horse, cow, dog, guinea-pig and white rat. In the case of the rabbit and cat no such organisms were detected.
2. Many of these acid-resisting bacilli resemble the tubercle bacillus and the smegma bacillus of man.
3. The acid-resisting organisms are undoubtedly of different species and there is good reason to believe that the term smegma bacillus denotes not a definite species but rather a group of bacilli having common staining properties.