2l6 BACTERIOLOGY 



diameter of I mm. ; show a gray-white central nucleus, with an irregular, 



indistinct, filamentous border, and an outer orange zone. In 7 days, the 



colonies are round, white, entire, and elevated. 

 Agar slant. Growth moist, glistening, porcelain-white, spreading. 

 Gelatin stab. In depth, growth filiform ; surface growth elevated, umbilicate, 



1 mm. in diameter. 

 Potato. Growth thin, whitish, becoming thick, pasty, and the color of putty. 

 Bouillon. Turbid ; no pellicle. 



Pepton rosolic acid. Decolorized in 7 days ; alkaline. 

 Litmus milk. Becomes darker, and afterward is decolorized. Indol not 



produced. Grow at 35-37. 

 Habitat. Soil. 



27. B. geminus Ravenel 



B. geminus-minor Ravenel: I.e. 



Morphology. Bacilli very short rods, with rounded ends, 2-4 times their 

 breadth ; occur singly. Motility slight ; flagella not demonstrated. 



Gelatin colonies. Deep: round, yellowish, granular, entire. Surface: yellow- 

 ish, granular, entire, becoming in 1-2 days elevated, convex, dense, and 

 pearly white. Colonies small, 1.5 mm. 



Gelatin stab. A filiform growth in depth ; on the surface, a bead, becoming 

 larger and more spreading, with corrugated edges. 



Potato. Growth thin, spreading, becoming, in 10 days, dirty white, moist, 

 and glistening. 



Bouillon. Turbid, with a slight pellicle. 



Pepton rosolic acid. Becomes cherry-red in 10 days. 



Litmus milk. Rendered alkaline. Indol produced. Nitrates reduced to 

 nitrites. Grow at 35-36. 



Habitat. Soil. 



28. B. aquatilis-sulcatus-quartus Weichselbaum 



Osterreichische Sanitiitswesen, 1889; Dyar, I.e., 359. 



From descriptions (Dyar), indistinct from the preceding. 

 Habitat. Water. 



29. B. primus-Fullesi Dyar 



I.e., 360. 



From descriptions, indistinct from B. geminus, except milk cultures emit a 



disagreeable odor. 

 Habitat. Water. 



