116 STORRS AGRICULTURAL EXPERIMENT STATION. 
S. lacticus IJIT.—This shows a pellicle on bouillon; the milk is usually acid 
and occasionally curdled, but in some cases shows no trace of acid to litmus 
paper. The potato growth is usually scanty or wanting, though sometimes 
more luxuriant. 
M. lactis acidi.—This name includes the smaller acid-producing cocci that 
have a luxuriant surface growth on various media. There are very many of 
them. Probably JZ. candicans of Fliigge belongs here. Their general charac- 
ters are as follows: 
Morphology.—A micrococcus. Size, .5@-1.24@. Gram stain is positive. 
Gelatine colony.—Not characteristic. The colonies are round, thin, smooth, 
rather opaque and white in color. On &tmus gelatine no acid is produced. 
Gelatine stab.— Needle growth and surface growth. 
Agar streak.—A moderate, white, smooth growth, which is sometimes rough. 
Fermentation tubes.—All fermentation tubes show an acid production, but no 
gas and no growth in closed arm. 
Bouillon.—A sediment and turbidity, but no pellicle. 
Milk.—Sometimes acid and sometimes not acid. Usually not curdled, 
though some cultures curdle the milk by acid production. Occasionally a 
slightly sour odor. 
Potato.—The growth is usually scanty and sometimes absent. It is whitish; 
not characteristic. 
Grows at 20° and 37°. Aerobic. 
This is the most common of the milk cocci. It is found almost constantly in 
common fresh milk, both here and elsewhere, where we have had an oppor- 
tunity of studying it. It is clearly very similar to S. lactts actdi Z//., the primary 
difference being in the amount of surface growth. We have studied very many 
different cultures of this type and naturally found many variations. The most 
noticeable points of variation are as follows: 
Size, from .5u-1.2u. Gelatine stab in two cases showed no surface growth; 
colony on gelatine varies much in thickness and is sometimes slightly yellowish; 
the litmus gelatine colony is occasionally acid; the growth on agar varies much 
in abundance, but is always more than in the lactic type. 
M. lactis gigas n. Ss. 
Morphology.—A very large coccus. Size, 1.54. Gram stain is positive. No ~ 
chains. 
Gelatine colony.—A round, thick, smooth, homogeneous, entire translucent, 
cream-white colony. 
Gelatine stab.—A needle growth is produced but no surface. 
Agar streak.—Growth is scanty, beaded, translucent and white. 
Fermentation tubes.—All three sugar bouillons are rendered acid but there is 
no growth in the closed arm and no gas. | 
Bouillon.—A sediment but no turbidity and no pellicle. 
Milk.—Becomes very slightly acid, sufficiently to curdle the milk in about 
four weeks. 
Potato,—No growth. 
Grows at 20° and 37°. Aerobic or facultative anaerobic. 
This coccus is characterized by its very large size and has been found several 
times by us in Middletown and Storrs. It was first isolated in 1896. 


