Lactobacillus hilgardii is redescribed and compared with other heterofermentative lactobacilli. The criteria of optimum and maximum temperature relations, fermentation of pentoses and other carbohydrates, rate of growth, type of growth, growth requirements, cell morphology, and the effect of pH on fermentation indicate that this and other “inactive” lactobacilli—L. fructivorans, L. trichodes, and Betabacterium caucasicum—are well-defined species. The name Lactobacillus desidiosus is proposed to replace Betabacterium caucasicum, in order to conform to accepted nomenclature.
