1895. ] NEW YORK ACADEMY OF SCIENCES. - 95 
the collection of the Bacteriological Department of Columbia 
College, marked “ Sarcina rosea. (3) The most common species 
on some plates exposed in the hallway of the 59th street build- 
ing, November I6, 1893, (4) In the air of my flat, W. 69th 
street. (5) A contamination from the air of the laboratory on 
certain plates. 
In this species the cells divide in two directions, forming di- 
plococci and tetrads, and it is consequently referable to the 
genus Merismopedia. In the state of early division a hemi- 
spherical appearance of the elements may be noted which is de- 
scribed by Bumm as a resemblance to the “gonococcus.” 
Hisenberg does not describe the cells as associated in pairs and 
fours, but this appearance may not always be well marked. 
Sarcina rosea is evidently closely allied to this species, but I 
do not venture to consider it identical, as it is described as a 
true Sarcina, and is said to liquefy gelatin rapidly. But neither 
of these characters are of great value when the exact composi- 
tion of the media is not known. 
VARIATION IN BrioLoGIcAL CHARACTERS. 
Liquefaction of gelatin.—Culture 1 produced the first signs 
of liquefaction in 14 days. Culture 3, after it had been in culti- 
vation some months, produced distinct liquefaction in 10 days. 
The same culture, when freshly obtained from the air, produced 
no liquefaction as long as the tube was retained (40 days). 
Culture 5 produced no liquefaction at first (30 days), but in a 
second culture traces of liquefaction were observed in 30 days, 
and in another later one in 19 days. In culture 5, hollows sink- 
ing into the surface of the gelatin, indicating liquefaction, were 
observed in 50 days. In culture 2, no sign of liquefaction was 
obtained till 30 days, although this culture had been in cultiva- 
tion in the College collection for some time. 
Action on Milk.—None of the cultures produced any coagu- 
lating effect in milk, before orafter boiling. Usually a fine pink 
growth of the cocci was obtained. : 
Reduction of Nitrates.—The effect of the growth of this or- 
ganism in the “nitrate solution” is to produce a moderate 
amount of reduction to nitrite. The test never yields more 
than a fairly strong pink color. The following are the variations 
observed: Culture 1 gave a very faint color in 4 days, faint in 10 
days, and quite a strong tint in 28 days. Cultures 2 and 3 pro- 
duced a faint color quite uniformly at different times from 6 to 
28 days. Culture 5 produced a faint trace only at the end of 28 
days, and culture 4 produced no reduction of the nitrate. 
Growth on Potato.—Quite often the cocci will not grow on this 
