Red Milk. 



be observed, which cause a glassy, transparent thickening of the 

 wrinkled yellowish-white velvety layer of the oidium covering, or 

 they penetrate into the depth of the jelly-like layer of the milk. 



Thus under certain conditions the Bacillus violaceus, Bacter- 

 ium janthinum, Bacillus lividus, and Bacterium amethystinus, a 

 water organism, may appear in violet spots (Schroeder, Zopf, 

 Maze, Fliigge and others). 



Greenish-yellow spots and discoloration of the entire sour 

 milk are produced by the Bacillus fluorescens which varies greatly 

 in its characteristics, at times liquefying gelatin, again only dis- 

 coloring it. It is a short rod with motility, but without spore 

 formation. 



A red coloring matter is produced by the Bacillus erytliro- 

 genes Hueppe, which coagulates milk, but liquefies it later through 

 peptonization, coloring the whey red. 



According to Gruber a flagellated short rod, the Bacillus lac- 

 torubefaciens is supposed to produce a slimy condition of milk 

 with the formation of a red coloring matter. Other bacteria such 

 as the Micrococcus cerasinum (Keferstein), the Sarcina rosea, the 

 Bacillus prodigiosus and others, form red spots. Red varieties 

 of yeasts have also been found. 



The author demonstrated through the examination of a dirty 

 and dry milk pail that the layers of color which adhered to dif- 

 ferent parts somewhat like red varnish consisted of blue-red yeasts 

 which had grown on the dried milk residue. The accumulation of 

 color was present in the yeast cells proper, which on examination 

 showed a reddish transparency. Their attempted cultivation was 

 unsuccessful. 



The discolorations of milk may vary from red, and pink, to 

 rust-color and orange. 



Yellow coloration sometimes only of the cream, at other times 

 of the entire milk is caused by the Bacillus synxantlvus (Schroter), 

 the Sarcina lutea, the Sarcina flava, and Bacterium fulvum and 

 others. Wild yeasts and moulds, which have been observed by the 

 author may also cause a yellow coloration of sour milk. The 

 Bacillus fluorescens, may at times cause a yellowish-green 

 discoloration. 



Other bacteria again show the action of their vegetation by 

 the development of a tenacious slimy consistency of the milk. 

 Strains and varieties of the peptonizing bacteria in which acid for- 

 mation is dissipated and the peptonizing action of which retracts 

 against the properties of producing rennet-like substances, may in 

 a few hours cause a casein coagulation, and thereby convey to the 

 milk a granular consistence. This defect is relatively rare, and on 

 the contrary the milk may become non-coagulable, slimy and bitter. 



More frequently, especially by keeping the milk in a warm 

 place, a change of the milk to a slimy consistence may be observed. 

 The action of the slime-forming bacteria may appear in two forms, 



