BACILLUS PROTEUS VULGARIS. 475 cause of death in case&an which considerable quantities are injected into the peritoneal cavity or blood-vessels. The bacilli do not seem able to multiply in the animal body in health, but can do so when there has been pre- vious injury to its tissues or when associated with patho- genic bacteria. In such cases, if.it be enabled to grow in considerable quantity, its toxin may cause pronounced symptoms. By various observers the proteus has been secured in culture from cases of wound and puerperal in- fections, purulent peritonitis, endometritis, and pleurisy. When the local lesion in which it grows is small, as in endometritis, the danger of toxemia is slight, but when spread over large areas, as the peritoneum, may prove serious. It is quite probable that in some of the cases in which blood-infection with the proteus has been found after death it did not exist previously, as the researches of Bordoni-Uffreduzzi have shown that the proteus quite regularly enters the tissues after death. While thus apparently unable to keep up an indepen- dent existence in the tissues during life, and important in the body only in conjunction with other bacteria, the proteus seems able to grow abundantly in urine and to produce primary inflammation of the bladder when in- troduced spontaneously or experimentally into that viscus. The inflammatory process may extend from the bladder to the kidney, and so prove quite serious. The Bacillus proteus has also been found in acute in- fectious jaundice and in acute febrile icterus, or Weil's disease.