76 BACTERIOLOGICAL EXAMINATION OF WATER. 



appearance, and project slightly above the gelatine ; under a 

 low power the deep colonies are circular, smooth rimmed, and 

 uniformly dark olive-green in colour ; the surface colonies at 

 the margin are lighter in colour, viz., more greyish-yellow. 

 The gelatine is not liquefied. In gelatine-stab there is a growth 

 after six or eight days, a row of small yellow colonies being 

 seen along the inoculation line. 



Micrococcus Radiatus. 



Described by Flugge and found by Adametz in water. It 

 occurs as medium-sized cocci, at times arranged in short chains, 

 more often in small heaps. In gelatine plates it forms in two 

 days large colonies, which have a yellowish-green iridescence. 

 Under a low power the colonies appear granular, sharply outlined, 

 with a slightly irregular margin ; at times a row of rays grows 

 out giving the colony a starfish-like appearance. The gelatine 

 at this stage liquefies, and in two more days the starfish rays 

 appear as a delicate and regularly arranged circlet of rays. In 

 two or three days a second circlet of rays may appear, and 

 eventually even a third circlet may be formed. In gelatine-stab 

 horizontal rays pass out from the stab, and above a funnel is 

 formed by slow liquefaction of the gelatine. 



Micrococcus Flavus Desidens. 



Found by Flugge in air and water. It consists of small cocci, 

 chiefly arranged as diplococci ; also found in short chains and 

 as triangles. In two days the colonies in gelatine appear as 

 yellowish white points, which often show on one side a finely 

 granular yellowish- brown projection. The surface colonies have 

 a lighter colour near the margin. After four days the colonies 

 in the depth are little changed ; the surface colonies, however, 

 have grown out to a diameter of 5 to 10 mm., and are circular 

 and lobular, of a pale yellow or brownish colour, forming slimy 

 expansions which slowly sink into a flat circular depression 

 formed by gradual liquefaction of the gelatine. In gelatine- 

 stab it forms a confluent, porcelain white, growth in the depth, 

 and a yellowish-brown slimy expansion on the surface, which 

 does not reach the margin of the tube ; in about eight days the 



