Observations on the taxonomy of the genus bacillus

Abstract

1. Though Smith's taxonomic classification for the genus Bacillus is largely satisfactory, the characteristics on which species of morphological groups 2 and 3 are separated are still inadequate. 2. Though nutritional characteristics have an undeniable taxonomic value, they are no more immune to the limits of variation than are other characteristics. 3. A more intensive study of the characteristics exhibited by a large collection of strains of these 2 morphological groups is indicated. 4. For the isolation of an adequate number of strains of these less well known species, elective or enrichment culture methods may be successfully exploited. 5. The growth requirements of Bac. firmus and Bac. lentus in morphological group 1 and some species of morphological groups 2 and 3 remain to be established. 6. The fundamental factors influencing organised movement and migration of colonies of certain species of bacilli remain an inviting challenge to the curious investigator.