18981 



MICEOSCOPICAL JOURNAL. 



Bacteria that Curdle Milk. 



By R. R. DINWIDDIE- 



Micrococcus uberis. — This bacterium is found in the 

 milk duct of the cow. The cocci are of medium size, 

 arranged in pairs, irregular groups, or sometimes chains 

 of four to six. They are non-motile and readily stained 

 by aqueous solution. They grow at 20 degrees to 37 de- 

 grees C. In agar streak culture, fig.l, surface growth is 

 free, white and spreading over the surface below while 



I 



above it is limited to the wire track. Surface, smooth, 

 moist and glistening. Potato culture, fig. 2, at 10 days, 

 shows a free growth limited to the wire track, raised, 

 white, granular. 



G-elatin stab cultures appear in fig. 3 (4 days) and fig. 

 4 (14 days) 22 degrees C. There is early fluidification, a 

 funnel-shaped depression which extends in 10 or 20 days 

 across the tube. In five weeks, half the medium is fluidi- 

 fied. 



