APPENDIX. 429 



(3) Bacilhis Fitzianus. Obtained from the dust of hay, and supposed to 

 be really a variety of the Bacillus subtilis. The colonies are brownish 

 yellow in colour with a dark opaque centre and sharp outline, those lying on 

 the surface of the gelatine are like brownish yellow gelatinous drops ; 

 organisms are from I to 2/z and upwards in length and about lju in thick- 

 ness, the longer rods are frequently bent at the ends ; there is distinct spore 

 formation ; sets up aethylic alcoholic fermentation, especially when glycerine 

 is present. 



II. The nutrient jelly is liquefied. 



A. Colonies are white ; nutrient substratum remains uncoloured. 



B. Colonies or nutrient substratum coloured, see p. 433. 



A. Colonies are white ; nutrient substratum remains uncoloured. 



a. Colonies branched or with processes. 



b. Colonies circumscribed without branches, see p. 431. 



a. Colonies branched or with processes. 



a. Colonies are non-motile. 



(3. Colonies motile and swarming, p. 430. 



a. Colonies are non-motile. 



(1) Bacillus anthracis, see p. 272. 



(2) Bacillus ramosus liquefaciens. Roundish colonies on plates with 

 radiating processes, the rounded disc looking as if it were surrounded by 

 a zone of hairs ; superficial colonies are oval or pear-shaped ; there is slight 

 liquefaction around the growth and a deep circular funnel is formed, which 

 is surrounded by concentric rings, which gradually increase in size ; run- 

 ning off from the funnel at right angles are a number of branches longer 

 near the surface and becoming shorter as the deeper layers are reached ; 

 the organism is a medium size slightly motile bacillus with blunted ends. 



(3) Bacillus subtilis (Hay bacillus}. Obtained from hay infusion that has 

 been boiled. Grows on plate cultures as white rounded colonies with radiating 

 processes ; liquefies gelatine on plates rapidly ; along the track of needle 

 causes liquefaction which commences at the surface ; first occurs as small 

 whitish colonies, which under a low power have a yellowish brown colour 

 with the hair-like margin, outside this is a narrow clear zone, beyond which 

 again is a greyish layer composed of radiate lines ; on potatoes and on agar 

 it forms a whitish moist creamy layer, which afterwards becomes somewhat 

 granular and dry ; is dryer and more wrinkled looking on agar than on 

 potatoes. Liquefies blood serum ; grows rapidly about 30 C. ; is strongly 

 aerobic ; is a motile organism about 6ju in length and about 2j.i in breadth 

 with slightly rounded ends, it divides and multiplies exceedingly rapidly ; 

 large well defined spores are formed (when the supply of nutrition is 

 gradually cut off), about i.2)it in length and .6/z in breadth. 



(4) Bacillus pneumoniciis agilis (or Bacillus of vagus pneumonia of rabbits). 

 Grows on gelatine plates as round dark granular colonies with slightly 

 roughened surface and margins ; after from 20 to 24 hours there are marked 

 movements in the middle of the colonies, and liquefaction takes place rapidly ; 

 in needle cultures in gelatine tubes rapid liquefaction of the medium occurs, 

 and a shallow funnel-like space, in which the gelatine is liquefied, is 

 formed ; growth on potatoes, spreads very rapidly over the whole surface as 

 a " chamois " red layer; on blood serum grows much more slowly and only 



