52 RepoRT OF DEPARTMENT OF BACTERIOLOGY OF THE 
than 2,000 per gram, on the pasteurized cheeses. The analyses 
give 2,500 per gram from the practically sterile milk and as hip 
as 66,000 per gram from the pasteurized milk. 
Troili-Petersson,® Gorini,’ Rodella,“™ and Harrison®* have shone 
that the growth of bacteria in cheese takes place in the form of 
distinct colonies. In the chloroformed cheese these colonies 
appear to be so widely separated that one is not often included 
inasample. Observe that while the examination of 6.17 II gave 
66,180 germs at 2 days and 84,460 at 1 month, it gave only 188 at 
2 weeks and the plates at 3 months, containing one-twentieth and 
one-fortieth of a gram of cheese respectively, remained sterile. 
In some instances, where unusually large numbers were found 
at the regular examinations, plates made a few daye later gave 
the usual small numbers. 
It may be suggested that these colonies are the remains of 
the growth which occurred in the milk previous to the addition 
of the chloroform. While this may be possible, it does not 
seem probable that colonies formed in the milk would remain 
intact and alive while passing through the pasteurizer, the 
paddles of which revolve 300 times per minute. Further our 
study of the efficiency of this same pasteurizer, as given in 
Bulletin 172, would indicate strongly that this does not occur. 
The chloroform was added within a few minutes after the heat- 
ing and our previous results have shown that the amount of 
chloroform present was sufficient,to inhibit growth promptly 
in the milk. The conclusion seems almost unavoidable that, at 
least in the 6.17 series, these colonies were formed in the cheese 
in the presence of the chloroform. It should be noted that even 
in these cases they appeared only in the cheese with small per- 
centages of chloroform. 
It is regrettable that while the germicidal action of chloroform 
in cheese is so marked there should be the occasional production 
of colonies as indicated in the above results. The most satisfac- 
* Troili-Petersson, Gerda, Studien ueber die Mikroorganismen des Schwed-_ 
ischen Giiterkases. Cent. Bakt. u. Par., II Abt., 11: 120-143; 207-215. 1903. 
*Goroni, C. Sur la distribution des bacteries dans le ftomages de Grana. 
Rev. gen. du Lait, 3: 287-293. 1904. 
™ Rodella, A. Einiges iitber die Bedeutung der direkten microscopischen 
Praparate fur das Studium des Kasereifungsprozesses. Cent. Bakt. u. Par., 
TL Abt TR 7A 3715 35.4 LOO 
“Harrison, F. C. The distribution of lactic acid bacteria in curd and- 
cheese of the cheddar type. Rev. gén. du Lait, §: 409-415. 1906, 
