ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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animals possesses tlie property of rendering venoms and toxins inert. 
The experiments were made with diphtheria toxin and rabbit’s bile, and 
with cobra venom and ox gall. 
Rise and Fall of Bacteria in Cheddar Cheese.* — Mr. H. L. Russell 
and Mr. J. Weinzirl thus summarise the results of their analytical 
study of the bacterial changes that take place in the curing of American 
Cheddar cheese. There is at first .a marked falling off in the number 
of bacteria in the green cheese for a day or so ; this is followed by a 
rapid increase, the number of bacteria being scores of millions per gram. 
After this the numbers sink until they become insignificant. The 
maximum development is hastened or retarded by external conditions, 
such as temperature, moisture, <fec. ; and this period marks the beginning 
of the physical change that occurs in the cheese in the earlier part of 
the breaking down of the casein. Though the lactic acid bacteria pre- 
dominate in milk, there are always liquefying or peptonising organisms, 
and as a rule bacteria capable of developing gaseous by-products. In 
ripening cheese the peptonising or casein-digesting bacteria are quickly 
eliminated ; the gas-producing bacteria disappear more slowly ; while 
the lactic acid bacteria develop enormously, until the cheese is partially 
ripened, when they too begin to diminish in numbers. The theory that 
the peptonising bacteria break down the casein in the cheese, as they 
do in milk, is regarded as improbable, and the view promoted is that 
the ripening of cheese is due to lactic acid bacteria, and this is supported 
by the fact that cheese made from pasteurised milk in which the lactic 
bacteria have been destroyed, fails to ripen in the usual way, while the 
addition of lactic acid starters permits the changes in the casein to 
occur in the normal manner. 
Effect of Sunlight on the Virulence of Tubercle Bacilli.t — The 
results of the experiments made by Dr. Migneco are confirmatory of 
those of Koch, who found that not only direct but diffused sunlight 
was harmful to tubercle bacilli. The author used linen and wool rags 
smeared with tuberculous sputum, and exposed these to the action of the 
sun. Water in which the exposed rags had been washed was also used. 
The presence of tubercle bacilli was demonstrated by means of injections 
into guinea-pigs. The author found that sunlight exerted a harmful 
influence on the bacilli of tubercle ; that the bacilli do not resist the 
sunlight longer than 24-30 hours, provided that the layer of sputum be 
not too thick ; and that the virulence of the bacteria gradually decreased 
after 10-15 hours. 
New Type of Tuberculosis.:]: — MM. Bataillon, Dubard, and Terre 
examined a tumour removed from the belly-wall of a carp. The tumour, 
which was about the size of a pigeon’s egg, showed on histological 
examination numerous giant cells, at the periphery of which were arranged 
in a radial manner a considerable number of bacteria, and these, in shape 
and staining reaction, resembled the bacillus of tubercle. From Bacillus 
tuberculosis they differed in their other biological characters, the most 
* Centralbl. Bakt. u. Par., 2 te Abt., iii. (1897) pp. 456-67. 
t Arch. f. Hygiene, xxv. p. 361. See Bot. Centralbl., 1897, Beih., p. 213. 
X C.R. Soc. Biol., 1897, p. 446. - L See Centralbl. Bakt. u. Par., l te Abt., xxii. 
(1897) p. 61. 
