SYSTEMATIC AND DESCRIPTIVE. 151 



lating a 5 to 8 per cent, nutrient gelatine. A 

 whitish line develops in the track of the inoculating 

 needle, and from it fine filaments spread out in the 

 gelatine (Fig. 37). Occasionally a little isolated 

 spot develops, from which rays extend in all direc- 

 tions, like the silky filaments of the thistle-down. 

 The filaments are more easily observed with a 

 magnifying glass. In a more solid 

 nutrient-gelatine the growth appears 

 only as a thick white thread. As 

 liquefaction of the gelatine progresses, 

 these appearances rapidly disappear, 

 and the growth subsides as a white 

 flocculent mass (Plate V., Fig. 3). In 

 exhausted culture-media, and some- 

 times in the blood, filaments are seen 

 in a state of degeneration. This has 

 also been observed in sections of the 

 kidney, etc., of a rabbit inoculated 

 with the anthrax bacillus, which had 

 died of septicaemia the following 

 morning. 



Test- tube- cultivations in nutrient agar- PURE CULTIVA- 



/^ (. i i TION OF THE 



agar. Cultivated upon a sloping sur- BACILLUS AN- 

 face of nutrient agar-agar a viscous GAT\ C NE-PEP- 

 snow-white plaque is developed (Plate TONE - BROTH - 

 XIV., Fig. i). Without access of air no cultivation 

 can be obtained, the bacilli being aerobic. This can 

 be demonstrated by embedding a piece of lung or 



* Crook shank. Reprinted from Lancet, 188^. 



