426 MICRO-ORGANISMS IN WATER 



BACILLUS AQUATILIS FLUOEE8CENS 



Authority. Lustig, Diagncstik der Bakterien dcs Wassers, p. 64. 



Where Found. Eisenberg is stated by Lustig (loc. cit.) to have found it in 

 water. 



Microscopic Appearance. Short thin bacillus with rounded ends. Non- 

 motile. 



Cultures. 



GELATINE PLATES. The superficial colonies resemble a fern-leaf and look 

 like mother-of-pearl. 



GELATINE TUBES. Grows only slightly in the depth, but produces a fluores- 

 cent and shining expansion on the surface. It does not liquefy the gelatine. 



AGAR-AGAR. Develops on the surface and exhibits a green colour. 



POTATOES. Eapidly produces an extensive grey mass. 



Remarks. It is aerobic. This bacillus appears to be identical with Eisenberg's 

 _B. fluorescent non-liquefaciens, see p. 425. 



BACILLUS YIEIDIS PALLE8CENS 



Authority. Frick, Vircliow's Archiv fur path. Anatomic, vol. cxvi. p. 292. 



Where Found. In Freiburg water by Tils (loc. cit.). 



Microscopic Appearance. Rather larger and more slender than the typhoid 

 bacillus. Often forms long threads. It is very motile. No spore formation 

 observed. 



Cultures. 



GELATINE PLATES. Forms small dark colonies in the depth. On the sur- 

 face the colonies form quite flat expansions, not rising above the surface of the 

 gelatine, with well-defined and irregular periphery. The contents are finely granu- 

 lar. At first the colour is grey, but after twenty-eight hours it becomes much 

 paler and turns to pale bluish green. The colonies are often slightly iridescent. 

 No liquefaction takes place. 



GELATINE TUBES. Grows principally on the surface and develops but very 

 slightly in the depth. The gelatine exhibits a blue green fluorescence, diminish- 

 ing from above downwards. 



AGAR-AGAR. Similar to gelatine. 



POTATOES. Forms a nut-brown moist expansion, whilst in the vicinity the 

 potato turns a dirty violet colour. 



BROTH. Forms a slight pellicle, which sinks to the bottom on the tube 

 being shaken. In the upper layers the liquid becomes slightly bluish green. 



Remarks. It is strictly aerobic. 



