2 88 . BACTERIOLOGY 



Gelatin colonies. Cochleate, with filamentous outgrowths like B. Zopfi. 



Agar colonies. Deep colonies : densely floccose in the centre, loosely fila- 

 mentous on the border. Surface colonies: round, watery, becoming 

 spreading, becoming dry and membranaceous, yellowish gray; border 

 lobate. 



Potato. Growth yellow, flat, spreading, slimy. 



Agar slant. A dry, spreading, membranous growth. 



Glucose gelatin stab. In 14 days a funnel of liquefaction, with filamentous 

 outgrowths in depth ; on the surface, a thick rugose membrane. 



Milk. In 3-4 days at 37 slimy thick, amphoteric slightly alkaline ; in 5 

 days, coagulated, slightly alkaline, becoming slowly peptonized ; a cheesy 

 odor. 



Bouillon. A surface growth. 



Habitat. Cheese. 



227. B. inflatus A. Koch 



Bot. Zeitung, 1888, 328. 



Morphology. Bacilli 0.6-0.8 : 4-5 p filaments. 

 Gelatin colonies. Round, seldom with outgrowths. 

 Gelatin stab. Short, delicate radiations ; liquefied slowly. 

 Potato. Growth thin, slimy, brown. 

 Bouillon. A smooth membrane on the surface. 

 Habitat. A contamination. 



228. B. erodens Ravenel 



I.e., 35- 

 Morphology. Bacilli straight, thick rods, 3-7 times their breadth ; occur 



singly; ends rounded. 

 Gelatin colonies. In 24 hours, minute, white, reticulate moruloid ; in 36 



hours, i.o mm., round, entire, dark gray; show swarming movements. 



In/} days, 2 mm. ; tunnels run out from edge of colonies, with often curled 



ends. 

 Agar slant. Growth thin, spreading, translucent, greenish, with white raised 



points. 

 Gelatin stab. In 3 days, a small funnel, curled at bottom, walls of main 



funnel eroded with minor curled tunnels from the former. 

 Potato. In 3 days, growth thin, moist, glistening, honey-colored. 

 Bouillon. Turbid, becoming clear ; no pellicle. 

 Pepton rosolic acid solution. Unchanged ; in 5-6 weeks slightly deeper in 



color. 



