MOUSE-SEPTICEMIA. 547 



The guinea-pig, which is generally the victim of labora- 

 tory experiments, is not susceptible to it. Field- and 

 wood-mice, cattle, horses asses, dogs, cats, chickens, and 

 geese are immune. 



When mice are inoculated with a pure culture they 

 soon become ill, lose their appetite, mope in a corner, 

 and are not readily disturbed. As the disease becomes 

 worse they assume a sitting posture with the back much 

 bent; the eyelids are glued together by adhesive pus; and 

 when death comes to their relief, in the course of forty 

 to sixty hours after inoculation, they remain sitting in 

 the same characteristic position. 



When the ears of rabbits are inoculated with the 

 bacillus from cases of erysipelas suis, a violent inflam- 

 matory edema and distinct redness occurs, much re- 

 sembling erysipelas. This lesion gradually spreads, in- 

 volves the head, then the body of the animal, and ulti- 

 mately causes death. 



When swine are affected, they are dull and weak, and 

 have a kind of paralytic weakness of the hind quarters. 

 The temperature is elevated ; red patches appear upon 

 the skin and swell and become tender. Death follows in 

 two or three days. Sixty per cent, of the diseased 

 animals die. 



In all animals the anatomical changes are much alike. 

 The disease proves to be a septicemia, and the bacilli can 

 be found in all the organs, especially the lungs and spleen. 

 They are few in number in the streaming blood. 



As the organisms stain well by Grain's method, this 

 stain is of great value for their discovery in the tissues, 

 and can be highly recommended. 



Most of the bacilli occupy the capillary blood-vessels ; 

 many of them are enclosed in leucocytes. The organs in 

 such cases do not appear distinctly abnormal, except the 

 spleen, which is considerably enlarged. The mesenteric 

 and other lymphatics are also enlarged, and the gastric 

 and intestinal mucous membranes are usually inflamed 

 and mottled. The bacilli also occupy the intestinal con- 



