BACTERIA IN THE DAIRY. PL 
baclHRIA IN TEE DAIRY: 
BY OH Swi CON N. 
——— 966 —— 
VoL CREAM RIPENING WITH PURE CULTURES OF BACTERIA. 
In the Annual Report of this Station for 1893, pp. 43-68, there 
were given a series of experiments upon cream ripening with a 
considerable number of species of bacteria which had been iso- 
lated from normal milk and cream. These experiments have 
been continued, with an interruption during the summer months, 
until the present time, and the details of the further experiments 
are given in the present article. 
The majority of the species of bacteria which are described 
below, and which have been used in all of the experiments upon 
which the present paper is based, have been obtained from milk 
products. Some of them have been isolated from ripening cream 
from several different places in Connecticut; some of them have 
been isolated from sour or sweet milk; and some from fermented 
milk; several of them were obtained from a lot of milk which 
had been sent to the Columbian Exposition from Uruguay as an 
illustration of certain food products. <A few were obtained 
from the air and several from water. In all cases, with the 
exception, therefore, of the water bacteria, the species in ques- 
tion may be regarded as normal milk bacteria, and their effect 
upon cream in its ripening and upon the butter subsequently 
obtained by churning the cream is, therefore, of considerable 
practical importance in enabling us to understand normal dairy 
products. ‘The description of the species will therefore be given 
in more or less detail. 
DESCRIPTION OF SPECIES. 
No. 34. 
Locality—Isolated from the air in Jackson Park at Chicago, in August, 1893. 
Morphology.—A spherical organism which has the characteristics of the genus 
Merismopcedia. Size.4 yp. 
Motility.—No motion. 
Relation to Air.—Grows well under mica plate. 
Temperature.—Grows profusely at 35° C., though not producing color. 
Grows also at 20°. 
