576 ANAEROBIC ORGANISMS IN GANGRENE 



Numerous other organisms are always found in association with the Bacillus 

 fusiformis in these lesions (vide ante). 



In wounds which have been treated with antiseptics many involution forms are 

 found : vacuolated bacilli with spindle-shaped ends or indented edges, and long 

 forms with constrictions which stain well and swellings which do not take the 

 stain. 



Staining reactions. The Bacillus fusiformis is easily stained by the basic 

 aniline dyes and best by carbol-fuchsin or one of the carbol- violet stains. 

 The bacillus is gram-negative. 



When stained with methylene blue portions of the organisms do not take 

 the stain : these unstained areas are not round and are obviously not spores, 

 as they do not stain by the methods used for staining spores. 



Sections. Fix the pieces of tissue for cutting sections in a saturated aqueous 

 solution of corrosive sublimate, and harden in increasing strengths of alcohol. 

 Stain in carbol-thionin. Vincent recommends the following technique : 



1. Stain for 10 minutes in carbol-thionin. 



2. Treat for a few seconds with the following solution : 



Absolute alcohol, 200 c.c. 



Iodine, - - . - 0*01 gram. 



3. Pour off the iodine solution and treat with absolute alcohol or alcohol 

 tinted with safranin or fluorescin. 



4- Clear in aniline oil. Wash in toluene. 



5. Mount in balsam. 



In sections stained by this method two layers may be made out : 



(a) A superficial layer 1-3 mm. thick, stained bluish grey, and composed of a 

 diphtheroid exudate remarkably poor in cellular elements in its superficial part but 

 in its deeper layers packed with bacilli. Below the layer of bacilli a mass of leuco- 

 cytes will be noticed. 



(6) A layer composed of dead tissue from which all trace of structure has dis- 

 appeared for part of its thickness. 



Note, (a) There are certain discrepancies in the different descriptions of the 

 Bacillus fusiformis. By the majority of bacteriologists the bacillus is regarded 

 as non-motile (Vincent, Muhlens, Ellermann, Weaver and Tunnicliffe) but Letulle 

 describes it as motile in saliva, and according to Vespremy it is provided with 

 numerous flagella : Plaut moreover describes very numerous, very delicate flagella 

 like a layer of cotton-wool all round the bacillus. Nearly all observers state that 

 the bacillus is gram-negative but Plaut is of a contrary opinion and is supported by 

 Jungano and Distaso. 



(6) The variations in the morphology of the Bacillus fusiformis have led Ellermann 

 to describe several species (three types) but of this there is no proof. Similarly, 

 there is no reason to suppose that the Bacillus fusiformis is merely a cultivation 

 form of a spirochsete as Silberschmidt has suggested. 



4. Cultural characteristics. 



Vincent had always failed no matter what media he used to obtain pure 

 cultures of the Bacillus fusiformis from cases of hospital gangrene or Vincent's 

 angina. 



If a portion of the exudate on the tonsil were sown on Martin's broth an impure 

 culture was obtained in which the bacillus took the form of elongated, non- motile 

 filaments. 



More recently however several observers utilizing Veillon's technique have 

 obtained pure cultures of the bacillus. It is a strictly anaerobic organism, 

 grows only at 37 C. and in media to which serous fluids have been added : 

 sugar appears to favour its growth. Eichmeyer lays stress on the importance 

 of keeping the material at a constant temperature of 37 C. and of heating 

 the medium to that temperature before sowing. In cultures the bacillus 



