516 MICRO-ORGANISMS IN WATER 



CLADOTHEIX INVULNEEABILIS 



I LIQUEFIES GELATINE | 



Authority. Acosta and Grande Rossi, ' Descripcion de un nuevo Clado- 

 thrix, Cladothrix invulnerabilis,' Centralblatt f. Bakteriologie, vol. xiv., 1893, 

 p. 14. 



Where Found. In water. 



Microscopic Appearance. The microscopic appearance is not given in the 

 Centralblatt. 



Cultures. 



AGAR-AGAR. In forty-eight hours small circular colonies of a dirty-white 

 colour are visible both along the needle's path in the depth and on the surface. 

 They cling so tenaciously to the agar that during their transference portions of 

 the latter are removed with them. Later the growth becomes silver-white, 

 and at a more advanced stage yellowish, and in about fourteen days appears as 

 a star with five to six rays, the centre exhibiting a small circular depression 

 surrounded by five to six protuberances and depressions. 



GLYCERINE -AGAR. Grows rapidly and abundantly. 



GELATINE TUBES. Produces a silver-white colony, depressed in the centre 

 but raised at the periphery. It resembles the growth in agar, but the gelatine 

 begins to liquefy slowly in the course of a few days, and growths attach them- 

 selves to the sides of the tube and to the edge of the fluid gelatine. 



POTATOES. Grows rapidly and abundantly, forming in forty-eight hours a 

 broad band where the needle has streaked the surface, consisting of small 

 white confluent chalk-like colonies, emitting an odour of damp soil. The 

 potato becomes blackish in colour. 



MILK. Forms a solid yellow layer on the surface, so that on inclining the 

 tube nothing runs out. Beneath this layer is a transparent liquid, underneath 

 which is seen the milk. 



COCOANUT MILK. Abundant cloudy growth. 



BROTH. Abundant cloudy growth. 



STERILISED WATER. Abundant cloudy growth. 



Remarks. When heated to 120 C. its development is retarded for six days, and 

 the growth is impaired. It can withstand six successive exposures to intermittent 

 sterilisation at 100 C. Potato cultures exposed for ten minutes to an electric current 

 ot fifty cells were not destroyed. It will grow equally well in the absence as in the 

 presence of air. 



