454 PATHOGENIC AEROBIC BACILLI 



than those from my original stock which had not been passed through a 

 susceptible animal. 



The mode of death in rabbits is quite characteristic. A couple of hours 

 after receiving in the cavity of the abdomen two or three cubic centimetres 

 of a liquefied gelatin culture the animal becomes quiet and indisposed to eat 

 or move about. Soon after it becomes somnolent, the head drooping for- 

 ward and after a time resting between the front legs, with the nose on the 

 floor of its cage. It can be roused from this condition, and raises its head in 

 an indifferent and stupid way when pushed or shaken, but soon drops off 

 again into a profound sleep. Frequently the animals die in a sitting posi- 

 tion, with their nose resting upon the floor of the cage between the front 

 legs. I have not seen this lethargic condition produced by inoculations with 

 any other microorganism. Convulsions sometimes occur at the moment of 

 death. 



The time of death depends upon the potency of the culture and its quan- 

 tity as compared with the size of the animal. From three to four cubic 

 centimetres of a liquefied gelatin culture usually kill a rabbit in from three 

 to seven hours. 



The rapidity with which death occurs when a considerable quantity of a 

 liquefied gelatin culture is injected into the cavity of the abdomen, and the 

 somnolence which precedes death, give rise to the supposition that the lethal 

 effect is due to the presence of a toxic chemical substance rather than to a 

 multiplication of the bacillus in the body of the animal. And this view is 

 supported by the fact that animals frequently recover when the dose admin- 

 istered is comparatively small and especially when it is injected subcuta- 

 neously. 



In all cases in which death occurs, even when but a few hours have 

 elapsed since the inoculation was made, I have recovered the bacillus in 

 cultures made from blood obtained from the heart or the interior of the 

 liver, and, as stated, these cultures appear to have a greater virulence than 

 those not passed through the rabbit. 



In sections of the liver and kidney stained with Loffler's solution of 

 methylene blue the bacilli are seen, and are often in rather long-jointed fil- 

 aments. 



95. BACILLUS PYOCYANUS. 



Synonyms. Bacillus of green pus ; Microbe du pus bleu; Bacil- 

 len des griinblauen Eiters ; Bacterium aeruginosum. 



Obtained by Gessard (1882) from pus having a green or blue 

 color, and since carefully studied by Gessard, Charrin, and others. 

 This bacillus appears to be a widely distributed 

 saprophyte, which is found occasionally in the 

 purulent discharges from open wounds, and some- 

 times in perspiration and serous wound secretions 

 (Gessard) . The writer obtained it, in one instance, 

 FIG. 155. Bacillus in cultures from the liver of a yellow-fever cada- 

 ver (Havana, 1888). 



Morphology. A slender bacillus with rounded 

 ends, somewhat thicker than the Bacillus murisepticus and of about 

 the same length (Fliigge) ; frequently united in pairs, or chains of four 

 to six elements; occasionally grows out into filaments. 



Biological Characters. An aerobic, liquefying, motile bacil- 

 lus. Grows readily in various culture media at the room tempera- 



