
CLASSIFICATION OF DAIRY BACTERIA. a! 
Milk; not curdied at either 20° or 36°, but rendered acid, and will curdle 
when heated. Butter made from cream has a sour, clean taste, but not much 
flavor. A strong, but not typical aroma. 
INO MLO (ee CN are.) 
Morphology; size, .6u by 1.2", variable. 
Gelatin plate; spreading into a thin, transparent surface colony, which later 
becomes thicker and brownish or yellowish. It may even form a thick, yellow- 
ish bead, half a millimeter in diameter. 
Gelatin stab; a good needle growth, white. On the surface an irregular, 
yellowish growth, spreading slightly and rather thick on the edge. 
Agar; a dull yellow, transparent, but not abundant growth. 
Potato; a thin, yellowish layer, which upon some moderately dry potatoes 
may be quite thick, but still yellowish. 
Milk; sometimes not affected in the room, but in other cases is curdled in 
about two weeks into a soft, lumpy, incomplete curd. At 36° the curdling is 
more complete, but still soft, and the reaction is amphoteric. It has no effect 
upon butter. 
This is the only non-liquefying organism found which curdles milk without 
rendering it acid. 
The next two organisms differ from the others in producing spores. 
No. 95.) (Rare:) 
Morphology, size, 1m by .6m, or in old cultures slightly larger. The old cul- 
tures show large oval spores, larger than the rods. 
Gelatin plate; an irreguiar surface colony, streaked over the surface with 
irregular contorted lines. Grows to the size of 2 mm. on the surface. 
Colonies under the surface are lobed. 
Gelatin stab; a good needle growth, with a thick, white, surface growth. 
Agar; very thick and opaque and white. Later becoming somewhat 
yellowish. 
Potato, very thick and transparent; of a whitish color, which later becomes 
dry and folded. ° 
Milk; does not curdle at 20°, though will when heated. At 36° curdles in 
three days. Cream is rendered acid and sour, and butter made therefrom has 
rather an unpleasant, sour, cheesy taste. 
No. 94. B&B. ubiquitous lactis. “7 ) 
Morphology, size, .8u by 1.24 tor.4“. In bouillon short chains are produced. 
A bipolar staining is shown, and spores are eventually produced in the middle 
of the rods. A non-staining capsule developed. 
Gelatin plate; round, white, opaque colonies, with a dark center, frequently 
raised to form a bead. 
Gelatin stab; abundant needle growth. Surface raised, white, forming a 
; prominent nail head. The center is more elevated than the edge. 
Agar; extremely irregular, spreading, thick, very white and smooth. 
Potato; grows with extreme rapidity, forming a ¢ransparent, white, glisten- 
ing, widely spreading growth, especially characteristic. 
