The L-Form of Haemophilus pertussis in the Mouse

An examination of Giemsa-stained preparations of lung tissue and peritoneal fluid from mice inoculated with Haemophilus pertussis shows that the bacillary form can change to the L-form of the organism in vivo. This transformation is more rapid and more complete in immune than in normal mice. The L-form, produced on Bordet-Gengou agar containing 1·5% (w/v) glycine, administered intranasally can revert to the bacillary form in vivo.