MICRO-ORGANISMS IX WATER 



BACILLUS LIMOSUS 



JJ.IQUEFIES GELATINE i 



Authority. Russell, ' Untersuchungen iiber irn Golf von Neapel lebende 

 l^acterien,' Zeitschrift fiir Hygiene, vol. xi., 1891, p. 196. 



Where Found. In sea mud near the coast, and also at a depth of 1,100 

 metres. 



Microscopic Appearance. A long bacillus with rounded ends, 1-25 /u. broad 

 and 3 or 4 p. long. Usually two or three individuals are joined together and ex- 

 hibit a slow, quiet, oscillatory movement (gelatine cultures), but when examined 

 from potato cultures isolated cells, shorter and fatter than those from gelatine, 

 are found which exhibit no movement. Forms bright shining spores at one end 

 of the rod. 



Cultures. - 



GKIATINK 1 'KATES. Forms in twenty-four to thirty hours almost transparent 

 centres surrounded by a slight depression. Under a low power numerous long 

 slender threads extend from the periphery into the adjacent gelatine ; later the 

 centre of the colony spreads out and overwhelms the filaments, and the whole 

 colony becomes circular and opaque, with a thick border of tiny thorn-like pro- 

 jections. In older colonies a thin pellicle forms on the surface and floccultnt 

 particles float below, whilst the edge retains its thorny appearance. 



(IKLATINK TrT!i:s. If sea-water is used in the preparation of the gelatine 

 the growth is more rapid, a funnel-shaped liquid depression forming in twenty- 

 four hours. In seventy hours the whole contents of the tube are fluid, and in 

 the lower portions light flocculent particles collect, whilst a thin and easily torn 

 pellicle forms on the surface. In ordinary gelatine it grows in the same manner, 

 only more slowly. 



A(iAU-.\GAK. Grows abundantly, forming a moist, white and shining ex- 

 pansion. 



POTATOES. - Grows well, producing a thin, clouded greyish white expansion, 

 which spreads for some distance over the surface. 



JliioTH. Renders it very turbid, producing a considerable deposit and 

 forming a thick tough pellicle on the surface. 



