288 J. S. LAWRENCE AND W. W. FORD 



protoplasm at the ends and thus have a characteristic appearance. 

 They are oval to cylindrical and measure 0.5 to 0.75 by 1.5 to 

 2.125 microns. The spores are frequently seen in pairs attached 

 by their protoplasmic remnants, and also sometimes in chains. 



Agar slant. Luxuriant, thick, white growth with a smooth 

 and glistening surface, spreading over the entire surface of the 

 agar. Some cultures show a delicate transverse wrinkling. 



Agar stab. Fine, slightly arborescent growth along line of 

 inoculation. Thick, white, wrinkled surface growth. 



Agar colonies. Surface colonies thick, raised, round or bizarre, 

 frequently show'ng dense, central nuclei. Under low power 

 granular with dense, central nuclei and spreading peripheries 

 made up of curved parallel strands. Deep colonies small, round 

 or irregular. Under low power irregular, mossy, with irregular 

 fuzzy margins. 



Litmus glucose agar slant. Thick, yellowish-white, moist 

 growth, spreading over the entire agar and wrinkling slightly 

 at the base when the culture is very active. Reaction in medium 

 acid in first few days but gradually alkali is produced and the 

 agar turns dark blue. 



Litmus glucose agar colonies. Surface colonies thin, translu- 

 cent, somewhat smaller than plain agar colonies. Under low 

 power granular with thin peripheries made up of curling parallel 

 strands. Deep colonies round or irregular. Under low power 

 irregular, mossy with irregular, fuzzy margins. Medium first 

 acidified and then made alkaline. 



Gelatin colonies. Surface colonies round, spreading concen- 

 trically and composed of a central loose mass of filaments denser 

 than the surrounding zone. Deep colonies are composed of 

 spherical masses of loose filaments with irregular, mossy or 

 bristling margins. Rapid iquefaction. 



Gelatin stab. Growth along hne of puncture with a rapid cup- 

 shaped liquefaction and scum production. 



Broth. Turbidity with ring growth in 24 hours and scum 

 formation in 2 to 3 days. Scum quickly precipitated. 



Peptone. Turbidity with scum formation on the second day. 

 Scum usually persists. 



