THE CLASSIFICATION OF BACTERIA 25 1 



123 a. B. Rheni 



Rhine water Bacillus (Burri) : See Frankland, Microorganisms of Water, 1894, 483. 



Morphology. Bacilli 0.7:2.5-3.5 ft, ends rounded, sometimes slightly bent. 

 In bouillon long filaments and chains. Motility rotatory and progressive. 



Gelatin colonies. Deep colonies dirty yellow dots, round, entire, granular. 

 Surface colonies convex, colorless, transparent, becoming yellowish, with 

 an outer zone of clear liquid gelatin. Microscopically, the borders are 

 wavy, and contents rough and irregular. 



Gelatin stab. Growth scanty, in depth ; liquefaction shallow, funnel-formed ; 

 yellow flocculent masses in the liquefied gejatin, and a bluish gray opal- 

 escence on the surface of the still solid gelatin. 



Glycerin agar slant. Growth thin, glistening, dry, tough, honey-colored. 



Potato. Growth moist, glistening, thin, flat ; orange- or rust-colored. 



Bouillon. Turbid, with a bright, orange-colored pellicle and a yellow deposit. 



Milk. Coagulated only partially in the upper part of the tube ; the cream 

 layer pale yellow ; serum alkaline. No growth at $7. No gas in glucose 

 bouillon. 



Habitat. Rhine River water. 



124. B. aurescens Ravenel 



I.e., 8. 



Morphology. Bacilli short, spindle-shaped, 2-3 times their breadth ; occur 

 singly. 



Gelatin colonies. Surface colonies minute whitish points, which are granular, 

 brownish, and entire. In 4 days 0.5 mm., yellowish brown, homogene- 

 ous, and entire. 



Gelatin stab. Slight growth in depth ; on the surface a yellow button ; in 18- 

 20 days a crateriform dry depression. 



Agar slant. Growth thin, yellowish, limited, becoming golden yellow. 



Potato. Growth yellow, thick, moist, spreading, becoming orange-yellow. 



Bouillon. Slightly turbid, with a dense, flocculent sediment. 



Litmus tnilk. Reduced, no acid, not coagulated. Jndol negative. 



Glucose bouillon. No gas. Grow at 36 . 



Habitat. Soil. 



125. B. cuticularis Tils 



Zeitsch. f. Hygiene, IX, 1890, 282. 

 Morphology . Bacilli 0.3-0.5 : 2 0-3.0 fi filaments. 



Gelatin colonies. Coli-like. The deep colonies are brown, irregular entire ; 

 the surface colonies have brown centres and colorless borders. 



