280 KOPINESS IN MILK, ETC. 



and cream ropy. It is fairly widespread in nature, and was also 

 detected by ADAMETZ (V.) in samples of milk from the Sornthal 

 (Switzerland). In addition to this, three other fission fungi (named 

 below) are found in Swiss soil, one of them being the Bacillus 

 Guillebeau c., which is not only dangerous to the cows (giving rise 

 to inflammation of the udder), but also produces various disturb- 

 ances in the dairy by making the milk "ropy" and the ripening 

 cheese "blown." The facultatively an aerobic Micrococcus Freuden- 

 reichii, 2 p in diameter, discovered by A. GUILLEBEAU (I.), is 

 still more injurious to milk, since, whereas the other organisms 

 just mentioned act only at high temperatures approaching blood- 

 heat, and therefore easily avoidable in practice this coccus is 

 active even at a moderate temperature, and turns milk ropy 

 within five hours at 22 C. The optimum temperature of de- 

 velopment is two degrees lower, and the microbe is destroyed by 

 an exposure of two minutes to boiling heat. It has frequently been 

 found in the district of Berne, and often causes considerable damage. 



Simultaneously with this last-named organism, a third microbe, 

 also endowed with the faculty of turning milk ropy, was intro- 

 duced by Guillebeau under the name of Bacterium Hessii. This 

 species, which appears in the form of actively motile rods, 3-5 p 

 long and 1.2 p broad, is less injurious than the one just described, 

 since the ropiness it produces in milk disappears directly acidifica- 

 tion sets in. 



The substantive cause of the mucinous condition may be of 

 three kinds. Either it is attributable to the swelling of the 

 membrane of the bacteria in question as is apparently the case 

 in those already alluded to as capsule bacilli, e.g. Actinobacter, 

 B. lactis viscosus, and also, according to the researches of W. 

 VIGNAL (I.), with B. mesentericus vulgatus or, secondly, the 

 milk-sugar is converted into a mucinous substance. This was 

 asserted to be the case by Storch for two species of bacteria 

 discovered by him, and was proved by G. LEICHMANN (III.) for 

 a bacillus isolated from ropy milk. This latter organism acts on 

 both lactose, cane-sugar, maltose, galactose, levulose and dextrose 

 (but neither on mannite, arabin, nor starch) in such a manner 

 that mucus and lactic acid are formed, together with a small 

 quantity of ethyl alcohol. In the third place, the ropy substance 

 can also be produced from the casein of the milk. According to 

 H. WEIGMANN, this latter cause operates in the formation of the 

 milk products known as 



163. Ropy Whey (Lange Wei) and Thick Milk 

 (Tsettemselk). 



The Swiss dairymen discard ropy milk for cheese-making, 

 being afraid of its causing "nests," i.e. places within the cheese 

 where the ripening proceeds irregularly. They therefore devote 



