3/6 BACTERIOLOGY 



Bouillon. Growth mostly at the bottom, with a few grayish flakes at the sur- 

 face and around the edges. The medium becomes a sherry wine color. 



Litmus milk. Becomes violet plum-colored, alkaline, and is apparently 

 peptonized. 



Glucose gelatin stab. No gas; growth in the upper 'part of the stab and on 

 the surface. Indol negative. Grows at 36. 



Habitat. Soil. 



6. Cladothrix intestinalis Ravenel 



I.e., 18. 

 Morphology. Long filaments, with false branching, which become segmented 



into rods of various lengths. The filaments have buds on them here anc 



there which are almost spherical. 

 Gelatin colonies. Deep : radiately arborescent. Surface : minute white 



dots; microscopically, they show grayish densely floccose centres, 



outside of which is a filamentous zone and outside of this a corona of 



coarse spear points or arborescent outgrowths. The surface growth 



becomes white and mouldy ; the gelatin is slowly liquefied and takes on a 



brownish color. 

 Agar slant. A narrow rough wrinkled stripe, adherent, friable ; agar bat 



little discolored. 

 Gelatin stab. In depth growth arborescent ; on the surface a whitish mouldy 



growth, radially folded ; gelatin slowly liquefied to a depth of 20 mm. ; 



a slight brownish discoloration of the medium. 

 Potato. Growth thin, white, wrinkled, becoming thicker and more rugose 



and finally dry, white, mouldy; medium, but slightly discolored. 

 Bouillon. Whitish flocculi at the bottom ; the medium the color of dark 



sherry wine. 

 Litmus milk. A lighter blue ; a thick pellicle on the surface and a dirty 



brown ring around the tube. In 7 days medium violet, color slowly 



discharged, alkaline, and apparently peptonized. 

 Glucose gelatin stab. No gas, growth as in plain gelatin. Indol probably 



present ; discoloration of medium interferes with the reaction. Grows at 



36. 

 Habitat. Soil. 



7. Cladothrix invulnerabilis Acosta-Grande-Rossi 



Centralblatt f. Bakteriol., XIV, 1893, X 4- 



Morphology. Not described. 



On Agar. Small round dirty white colonies, very adherent, becoming silvery: 



white, later yellowish, and in 14 days distinctly stellate in form, umbili- 



cate in centre. 



