492 MICROORGANISMS IX WATER 



GREY COCCUS 



LIQUEFIES GELATINE I 



Authority. Maschek, Jahrcsbcricht dcr Obcrrcalschulc zuLcitmeritz, 1887. 



Where Found. In water. 



Microscopic Appearance. Occurs as diplococci and in chains. It is not 

 motile. 



Cultures. 



GELATINE PLATES. Colonies only appear on the surface. They are irregular 

 and have a dark centre. Under a low. power the centre appears to be 

 surrounded by a woven network green in colour. The gelatine is liquefied in 

 about six days and an odour of bad eggs is emitted. 



GELATINE TUBES. Grows only on the surface and rapidly liquefies the 

 gelatine. 



POTATOES. Forms a bluish grey expansion. After about five weeks a smell 

 of bad eggs is noticeable. 



MICROCOCCUS CANDICANS 



I LIQUEFIES GELATINE | 



Authority. Fliigge, Die Mikroorganismen, IHSO, p. 173 ; also Percy 

 Frankland, 'Studies on some new Microorganisms obtained from Air,' Phil. 

 Trans., 1887, vol clxxviii. p. 270. 



Where Found. In air and water. 



Microscopic Appearance. Cocci of irregular size, the larger ones being 1 n 

 in diameter. They appear gathered together in groups, but exhibit no character- 

 istic arrangement. Not motile. 



Cultures. 



GELATINE PLATES. The colonies are milk-white, and under a low power they 

 are seen to have a smooth edge, whilst the interior is granular. The older 

 colonies are somewhat irregular in shape ; the less developed ones are, however, 

 nearly circular. 



GELATINE TUBES. After four days there is a surface depression containing 

 an intensely white and opaque mass. As the cultivation becomes older liquefac- 

 tion slowly proceeds downwards, the liquid being highly glutinous and turbid. 

 The mode of liquefaction varies according to the temperature : in warm weather 

 or at 22 C. it takes place in a long narrow funnel, whilst at a low temperature 

 it is mostly confined to the surface. (Percy Frankland.) Fliigge does not 

 appear to have noted its liquefying properly. 



AGAK-AGAR. Produces in three days a vigorous growth forming a smooth and 

 dazzling white mass, resembling a moist, patch of Chinese white. (Percy 

 Frankland.) 



POTATOES. Forms a rapidly spreading, white, slimy expansion. 



BROTH. Benders the liquid turbid and produces a white deposit. No pellicle- 

 is formed. 



