The suspension of tubercle bacilli was injected in the peritoneal cavity of guinea-pigs or rabbits, and the lymph fluid was taken from ductus thoracicus after elapse of various times from the injection. Microskopical findings of tubercle bacilli in the lymph fluid are as follows. When the suspension of tubercle bacilli is injected in the peritoneal cavity, the bacilli are found in or out of phagocytic cells in the lumph fluid of ductus thoraticus. When phagocytic cells are injected in peritoneal cavity, the bacilli are found mostly in phagocytic cells of the lymph fluid.