426 MICRO-ORGANISMS IN WATER 



BACILLUS AQUATILIS FLUOEESCENS 



Authority. — Lustig, Diagtwstik der Bahterien des WasserSj p. 64. 



Wliere 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.— Rapidly produces an extensive grey mass. 



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

 B. fluorescens non-liquefaciens, see p. 425. 



BACILLUS VIEIDIS PALLE8CENS 



Authority. ^Frick, Virchow^s Archiv filr path. Anatomies vol. cxvi. p. 292. 



Where Found. — In Freiburg water by Tils {loc. cit..). 



Microscopic Appearance. — Eather 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-deflnedandirregularperiphery. 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 Hquid becomes slightly bluish green. 



Remarks. — It is strictly aerobic. 



