PLATE XX. 



BACILLUS PROTEUS VULGARIS. 



This organism is introduced as one of the most common of those causing putrefaction, 

 though different varieties of the bacillus coli are almost as ubiquitous. 



Although by some, putrefactive organisms are not classed as pathogenic, because they are 

 not the causes of any process differentiated clinically as a disease, they are pathogenic in 

 the wider and truer sense, since putrefaction plays so important a part in the sepsis of 

 wounds and in the toxa;mia accompanying cancrum oris, the ulceration of extensive carcino- 

 mata of the alimentary and respiratory passages and conditions of a like kind. 



FIG 2. 



An '' Impression preparation 1 ' from a gelatin culture of eighteen hours. 



Carbol fuchsine, washed in water weakly acidulated with acetic acid. The culture was 

 made by streaking a Petri capsule (after the jelly poured into it had set) with a straight 

 platinum wire infected from a pure culture of the organism. The impression preparation is 

 obtained by allowing a cover-glass to fall upon some part of the streak of growth and then 

 gently raising it by one edge, when the line of culture is brought away adhering to the under 

 side of the glass ; the specimen is then stained in the usual way. 



The preparation shows the early or filamentous stage in the growth of the bacillus, which 

 is highly pleomorphic, whence its name of Proteus. 



The streak (of which one edge is depicted) consists of long, closely-matted, unbranched 

 filaments arranged in strands. As seen at the free margin, some are sharply re-curved upon 

 themselves. 



The organism figured was isolated from macerating muscle, the actual material being beef 

 steak, which was minced and incubated in distilled water at 37 C. 



FIG. i. 



Ail impression preparation of a similar streak culture at a later stage when the gelatin 

 was in process of liquefaction. Carbol fuchsine, washed in acidulated water. 



The filaments have mostly divided into short rods, often constricted across the middle or 

 in pairs end-to-end as diplo-bacilli. Here and there longer rods occur and filamentous 

 forms, but the longer of the latter have not been introduced. 



