14 QUATERCENTENARY STUDIES IN PATHOLOGY 



possessed of feeble motility. It has a considerable tendency to spore ; 

 the spore is located at its centre or at one end ; and occasionally, 

 especially after incubation in its native liquid, it assumes a drum-stick 

 configuration, indistinguishable from that of the Bacillus Tetani. Most 

 of the usual aniline dyes stain it readily, and the colour is not discharged 

 by Gram's process. These staining reactions hold good of the organism, 

 both when taken directly from the carcase and when in culture. 



It is a strict anaerobe, and grows on various media but most 

 characteristically on alkaline glucose-beef-tea and glucose-gelatine, each 

 covered with olive oil. The glucose-beef-tea becomes turbid after four 

 to five hours' incubation at 38° C, and continues so for days while 

 incubation is proceeding. If removed from the incubator after, say, four 

 days' growth, the culture begins to settle down slowly at the bottom of 

 the tube in a fine precipitate of greyish colour. It does not tend to 

 agglomerate in a granular form, as in the case of Braxy, nor to become 

 attached to the sides of the tube. During the process of germination 

 much gas is evolved which possesses a distinctly putrefactive odour. 



Examined microscopically, the culture is found to be composed of 

 thick stout rods, somewhat longer possibly than in the original peritoneal 

 liquid, slightly motile when first removed from the incubator, losing this 

 characteristic later on. Their actual measurements were found to be: — 

 4-2 X r4/x, 5*6 X i/x, 7*0 x i*4/x, and 14 x r4/x. 



The ends are again rounded, but usually the growth is free from 

 spores. Even when the medium has been strongly alkaline to begin 

 with, the Braxy organism will render it acid after a few hours' growth. 

 The Louping-ill bacillus acts in a like fashion, but slower, and this 

 probably accounts for germination being more protracted in the latter 

 than in the former case. 



Surface cultures on glucose agar grow luxuriantly ; along the central 

 streak formed by the inoculating wire, and from each side of this, some- 

 what arborescent processes extend outwards, rendering the sides of the 

 central streak very irregular. Such cultures are not particularly diagnostic. 



The stab-culture on glucose-gelatine, however, grown at 21° C, is very 

 characteristic. In order to observe it, the gelatine should be covered with 

 olive oil, and the inoculation made with the platinum wire through this. 

 Quite a week will elapse before the growth reaches its best. 



From the surface there passes downwards a grey-coloured streak for a 



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