236 
terial content of the oyster is not directly de- 
pendent upon the number of organisms present in 
the sea-water, nor is it the direct effect of tem- 
perature, but is rather due to some cause lying 
within the oyster itself. Possibly during the 
colder months the oyster enters a state of hiberna- 
tion, when no bacteria are taken in and those 
already within are gradually eliminated. 
Variation in Acid Production of Colon Bacilli 
from Different Sources: WinLIAM W. Brown. 
During the sanitary survey of Narragansett Bay, 
Rhode Island, under the direction of Professor 
Gorham, oysters were taken from 242 stations to 
determine whether the distance of the oysters from 
the source of the pollution had any relation to the 
amount of acid the colon bacillus was able to 
produce in dextrose and lactose broths, with the 
hope of determining whether pollution was recent 
or remote. But the factors governing such an 
experiment as the tides, currents and winds were 
so variable that the author could only draw a 
comparison between the amount of acid produced 
by colon freshly isolated from feces and the colon 
isolated from oysters. Oysters were taken from 
242 stations in the bay, some located in badly pol- 
luted areas, while some were taken from condi- 
tional zones (sometimes colon-positive, again colon- 
negative). In all cases the oysters were examined 
according to the standard methods of the com- 
mittee of the Laboratory Section of the American 
Public Health Association. The fecal colon were 
isolated from the stools of Italian immigrants. 
The dextrose and lactose broths used in the experi- 
ment were made according to standard methods, 
except that meat extract was used in all cases. 
Titrations were made with N/20 sodium hy- 
droxide into boiling solutions. 
From the titrations it was noted that: 
1. The optimum temperature for acid produc- 
tion by the colon bacillus is 37° C. 
2. No matter how great the quantity of medium 
inoculated with the colon bacillus, the same per 
cent. of acidity is obtained. 
3. More acid is produced in dextrose broth than 
in lactose broth by the colon bacillus. 
4. The amount of sugar present in the medium 
has a direct relation to the amount of acid pro- 
duced. 
5. Bacillus coli freshly isolated from feces pro- 
duces more acid in dextrose and lactose broth than 
Bacillus coli isolated from oysters. 
Mutations in Microorganisms: D. H. BERGEY. 
The success which seems to have attended the 
SCIENCE 
[N.S. Von. XXXV. No. 893 
attempts to produce mutation in some of the ani- 
mal organisms, especially Trypanosomes, stimu- 
lated the hope that it would be possible to produce 
similar mutations in bacteria. In fact such muta- 
tions have been encountered, notably those de- 
seribed by Neisser, Massini and others. I have 
selected a typical colon bacillus, isolated from 
feces, as a desirable organism with which to at- 
tempt to produce mutation forms. The success 
which Altmann and his associates had in changing 
the immunity reactions of the colon bacillus, sug- 
gested that it might be possible to change some of 
its other characteristics. With this object in view, 
I exposed the colon bacillus to various organic and 
inorganie substances, added to ordinary bouillon 
for varying periods of time. I then tested these 
organisms as to their general biological characters 
and the immunity reactions. Among the sub- . 
stances to which the culture was exposed were 
copper sulphate, chloroform, picrie acid, resorcinol 
and horse serum. Thus far none of the biological 
characters of the organism have been altered— 
either increased or decreased to any appreciable 
degree. The immunity reaction, especially the 
agglutination reaction, appears to show evidences 
of alteration. These alterations are most marked 
in the race exposed to horse serum, though all of 
the chemicals employed seem to so change the 
organism as to inhibit agglutination altogether 
or permit its manifestation only in serum of high 
agglutinative power. The alterations in the char- 
acters of the organism are insufficient in degree 
to warrant one in classifying them as mutations. 
The Antiseptic and Bactericidal Properties of 
Egg-white: Leo FE, RETTGER and JOEL A. 
SPERRY. 
Normal egg-white possesses marked antiseptic 
and bactericidal properties towards certain bac- 
teria, particularly the members of the subtilis 
group. B. subtilis and B. megatherium were de- 
stroyed almost instantaneously when introduced 
into test tubes containing the whites of hens’ eggs. 
Certain strains of B. coli and B. typhi were quite 
susceptible, while others were but slightly affected. 
The same thing was found to be true of B. pul- 
lorum (Rettger). With respect to the last-men- 
tioned organism the degree of resistance bore a 
definite relationship to the virulence, the more 
virulent strains showing the greater resistance to 
the action of the egg-white. 
Proteus Zenkeri was quickly destroyed, while 
Proteus vulgaris was less rapidly influenced and 
Proteus mirabilis suffered but little, if any. 
