SAPEOPHYTIC MICROCOCCI. 219 



the puncture cultivation white colonies, which remain 

 isolated, form in the deeper parts after 4 or 5 days ; 

 on the surface there is a moderately large knob, at first 

 rose-coloured, and later of a cinnahar tint. The gela- 

 tine is not in the least liquefied. The growth is some- 

 what slower on potatoes. It occurs frequently as an 

 impurity on old cultivations. 



Micrococcus flavus liquefaciens.* 



Comparatively large cocci, arranged for the most part 

 in twos or threes, or also in masses. They form small 

 yellow colonies on gelatine plates after two days, around 

 these a shallow depressed zone can be seen (similar to 

 the Staphyloc. aureus). The youngest colonies are 

 (as seen under a low power) circular or oval, or also at 

 some parts irregular ; their surface is finely granular ; 

 their contour sharp but finely toothed ; their colour 

 yellowish brown. The superficial colonies, which are 

 already causing liquefaction, and are distinctly yellow, 

 still show the remains of the deep colony in the centre ; 

 the border forms a ring with a sharp outline which is 

 here and there interrupted by heaps of cocci, and ulti- 

 mately several neighbouring colonies coalesce. The 

 ring is separated from the centre by a broad clear zone, 

 in which we see isolated, radially arranged lines of 

 cocci. The whole colony has in this stage a diameter 

 of 4 6 mm., and resembles microscopically the wheel 

 of a waggon. In test tubes spherical yellow colonies 

 appear in two days along the puncture track ; these 

 become confluent, and soon liquefy the jelly, so that 

 after 8 days the tube contains an upper zone filled 

 with clear fluid with the yellow masses of organisms 

 at the lower part. It is comparatively common. 



Micrococcus flavus tardigradus.^ 



Large spherical cocci, showing at times peculiar dark 

 poles ; for the most part arranged in masses. Grows 

 extremely slowly. After 6 days the deep colonies in 



* Gottinger hygienisches Institut. f Ibid. 



