Abstract
Immunodiffusion analysis of Mycobacterium lepraemurium indicated the presence of at lease six antigens. Comparative analysis of the M. lepraemurium antigen-antibody system with similar systems established for other mycobacterial species, showed that M. lepraemurium shared up to two antigens with other species. Although our observations are in accord with some of the studies on the antigenic mosaic of M. lepraemurium, they are in disagreement with the observations of Stanford (1973) concerning a close serological relationship of this organism to M.avium. This incompatiblity cannot be explained satifactorily at present.