I12 STORRS AGRICULTURAL EXPERIMENT STATION. 
Il. Types that produce acid in dextrose or other sugars. 
S. lactis fuluus n. s. A brownish-red Streptococcus. This was obtained 
once directly from the udder and once from city milk. Another culture was 
obtained from stable dust which agree in all points except those indicated in 
brackets. 
Morphology.—A streptococcus. Size, .7u. Gram stain is positive. 
Gelatine colony.—Small and dense, 5 mm. in diameter, rather thick, round, 
white. The colony in litmus gelatine is acid. [Brownish-pink to orange. ] 
Gelatine stab,— A needle growth and a thin surface growth. 
Agar streak,—Luxuriant, thick, moist, translucent, reddish-brown [orange- 
yellow]. 
Fermentation tubes—All three sugar bouillons rendered acid; there is no gas 
vor closed arm growth. 
Bouillon.—A sediment, turbidity, but no pellicle. [No turbidity.] 
Milk,—Is acid and curdles. 
Potato.—Luxuriant, brown. 
Grows at 20° and 37° — Aerobic. 
One culture obtained from New York milk shows some rather striking charac- 
ters, and we recognize it as a separate variety as follows: 
Variety A.—This agrees with the above except in the following: Size, 
1.2u-1.4@. Gram stain negative. Gelatine colony ringed and irregular, show- 
ing acid in litmus gelatine. Bouillon with a pellicle. Milk, curdled acid at 37° 
only. Potato has luxuriant growth and is discolored. 
M. lactis aureus n.s. Many different cultures of yellow, acid Cocct have 
been found in this vicinity, from Canada and New York. They are found in 
milk, in cheese, in butter, and in stable dust. Although they do not liquefy 
gelatine, we are confident that they are to be looked upon as non-liquefying 
forms of Staph. pyogenes aureus. (See p. 121.) The general description is as 
follows: 
Morphology.—A micrococcus. Size, .54-1.24. Gram stain positive. 
Gelatine colony.—Round, moderately thick, smooth, translucent colonies, of 
a lemon-yellow color, Litmus yelatine is acid. 
Gelatine stab.—A needle growth and a yellow surface growth. 
Agar streak,—Luxuriant, moderately thick, smooth, translucent, yellow. 
Fermentation tubes.—All sugar bouillons are rendered acid, but there is no 
gas, Occasionaly there is growth in the closed arm. 
Bouillon.—A sediment and turbidity, and rarely pellicle. 
Milk.—Rendered acid and usually does not curdle. Some cultures, however, 
curdle milk after several days at 37° Milk may be rendered yellowish. 
Potato.— Usually a moderately thick, yellow growth, with the potato dis- 
colored. 
Grows better at 37° than at 20°. Facultative anaerobic. 
Among the many cultures which we have studied, variations are found in the 
following points: Size, from .5u-1.2". Litmus colony is sometimes acid and 
sometimes not. Color varies from lemon-yellow to pale-yellow. In a few 
cases there has been closed arm growths in the dextrose, and sometimes in lac- 
‘tose. In two cultures a pellicle formed on bouillon. Milk always acid but 
