6 QUATERCENTENARY STUDIES IN PATHOLOGY 



the central cone stood bare, and the fluffy dots were well picked out in 

 the medium, which had become dusky-looking, and slightly more opaque. 

 Usually only a very few gas bells developed. 



Grown aerobically on surface culture, after a long incubation of 

 weeks, the bacillus caused a slight liquefaction of the gelatine and a 

 greyish filmy deposit. 



Growth on Agar. 



On several occasions the bacillus was isolated by plating out in the 

 ordinary manner, and growing under hydrogen at 37° C. After three 

 days, the typical colony had the following appearances : — It was about 

 the size of a large pin-head, rounded in shape, with sharply-defined 

 margin, and had produced a faint, bluish-white opalescence, of equal 

 density throughout the colony. Microscopically, a small colony consisted 

 of a large number of small dots, whilst a larger colony consisted of an 

 agglomeration of these smaller colonies. 



In stab culture a very copious evolution of gas had torn up the 

 medium so that nothing characteristic except a greyish line along the 

 track of inoculation was observed. 



A surface culture, grown anaerobically after 24 hours, showed roundish, 

 small, discrete colonies, which, later, ran together and spread themselves 

 out as a fine film over the surface. 



Bacillus of Louping-lll. 



Growth on Bouillon. 



After 12 hours' incubation, there was marked turbidity of the medium 

 with copious evolution of gas collecting as a fine foam beneath the oil. 

 After 48 hours' incubation, the medium became clear and distinctly acid 

 in reaction, and the growth was deposited at the bottom of the tube in 

 the form of a greyish-white mass. Examination in the fresh condition at 

 varying periods of the incubation revealed the presence of a large rod 

 with blunted ends, and broad in proportion to its length. The bacillus 

 was only faintly motile, and no spores were visible until the incubation 

 had been carried out for 36 hours, at which period a single small, 

 centrally placed, refractile body had become apparent, which, later, 

 increased in size producing an oval swelling in the centre of the bacillus. 



(406) 



