108 BACTERIOLOGY 



a lemon-yellow colour ; the thrust-culture slowly liquefies 

 the gelatine, a yellow mass being found in the deeper part. 

 Surface cultures on agar exhibit a lemon-yellow coating, 

 which later becomes brownish. 



Micrococcus flavus liquefaciens and Micrococcus desidens. 

 Both have been described by Fliigge. The former has 

 larger, the latter smaller elements frequently arranged as 

 diplococci, and both form yellowish-coloured collections on 

 discs of potato. On gelatine plates small round yellowish 

 colonies occur, which begin to liquefy the gelatine in from 

 one to two days. Thrust-cultures liquefy in a few days, 

 earlier in the case of Micrococcus liquefaciens than with 

 Micrococcus desidens, and when the elements have sunk to 

 the bottom of the funnel-shaped fluid area, a slight yellow 

 coloration forms below. 



Sarcina alba. The Sarcina alba grows slowly on gelatine 

 plates in little round white colonies, and in the same manner 

 along the track of the thrust in the test-tube, forming in 

 the latter a small white head on the surface. It also grows 

 very slowly on potatoes, in the form of a whitish-yellow 

 deposit round the site of inoculation. Gelatine is very 

 slowly and only very slightly liquefied, 



Sarcina Candida. The microbe of this name, found by 

 Keinke in breweries, shows shining white colonies on 

 gelatine, which later become yellowish and very soon 

 liquefy. On agar there appears a white deposit with smooth 

 edges. 



Sarcina aurantiaca. Small smooth-edged colonies appear 

 on the gelatine plate, having a dotted granular aspect when 

 seen under a low power, and an orange-yellow colour. 

 Thrust -cultures liquefy slowly along the entire track, and 

 excrete an orange-yellow pigment at the surface ; but when 

 they have stood for a longer time, the principal mass sinks 

 to the bottom and the superficial part of the medium 



