DESCRIPTION OF PLATE II. 

 Pure-cidtivations of Bacteria. 



Fig. 1. — In the depth of Nutrient Gelatine. A pure-cultivation of Kochs 

 comma-bacillus (Spirillum cbolerEe Asiaticse) showing in the track of 

 the needle a funnel-shaped area of liquefaction enclosing an air-bubble, 

 and a white thread. Similar appearances are produced in cultivations of 

 the comma-bacillus of Metchnikoff. 



Fig. 2. — On the surface of Nutrient Gelatine. A pure-cultivation of Bacillus 

 typhosus on the surface of obliquely solidified nutrient gelatine. 



Fig. 3. — On the surface of Nutrient Agar-agar. Pure-cultivation of Bacillus 

 indicus on the surface of obliquely solidified nutrient agar-agar. The 

 growth has the colour of red sealing-wax, and a peculiar crinkled 

 appearance. After some days it loses its bright colour and becomes 

 purplish, like an old cultivation of Micrococcus prodigiosus. 



Fig. 4. — On the surface of Nutrient Agar-agar. A pure-cultivation obtained 

 from an abscess (Staphylococcus pyogenes aureus). 



Fig. 5. — On the sv/rfaee of Nutrient Agar-agar. A pure-cultivation obtained 

 from green pus (Bacillus pyocyaneus). The growth forms a whitish, 

 transparent layer, composed of slender bacilli, and the green pigment 

 is diffused throughout the nutrient Jelly. The growth appears green by 

 transmitted light, owing to the colour of the jelly behind it. 



Fig. 6. — On tlie surface of Potato. A pure-cultivation of the bacillus of 

 glanders on the surface of sterilised potato. 



