BACILLUS FCETIDUS LACTIS 185 



bacillus prepares the soil for that of butyric acid. The 

 stringy substance comes from the material of which the 

 envelopes of the bacteria are formed, and is probably meta- 

 morphosed cellulose, as in the case of Bacillus mesentericiis 

 vulgatus, which also has the power of setting up a slimy 

 fermentation. 



Such fermentation is also originated, as Loffler found, 

 by the Bacillus lactis pituitosi, which consists of thick curved 

 rods very rapidly breaking up into segments like cocci. 

 The colonies on gelatine plates are radially striped, and the 

 gelatine is not liquefied. On potato a greyish-white coating 

 develops. 



Bacillus actinobacter. — Duclaux very frequently found in 

 milk fine non-motile rods, partly isolated, partly arranged 

 in pairs, but always furnished with jelly-like capsules, and 

 which rendered the milk gelatinous and viscid. The 

 capsules are retained in artificial cultures in glycerine 

 solutions, whereas in growths in bouillon and solutions of 

 sugar they are lost. Development can take place either in 

 the presence or absence of oxygen. 



Bacillus foetidus lactis. — Jensen isolated a bacillus from 

 milk which imparts to it and its products a nauseous, 

 sweetish, putrid odour and taste. The bacillus shows short 

 thick rods, with rounded ends and active motility. Gelatine 

 is not liquefied. Superficial colonies with the lustre of 

 mother-of-pearl occur on plates. In thrust-cultures a slimy 

 growth appears on the surface, and an abundant develop- 

 ment takes place along the track of inoculation. On agar 

 there is a formation of large lenticular bubbles of gas. 



Bacillus cyanogenus. — The cause for the development of 

 a blue colour in milk is to be sought for in the Bacillus 

 cyanogenus, described by Ehrenberg as Bacillus sijncyauus, 

 and which was studied by Hueppe and Neelsen. The 

 bacillus of blue milk consists of small, actively-motile rods 



