EXPERIMENT STATION BULLETINS. 



311 



'Constant letter "j" represents the lactic micro-organism. 

 ^Variable letters, a, b, c, etc., the associate micro-organism. 

 ^Counts and acidities made at the same time unless otherwise designated. 



<The column indicating the number of bacteria introduced, refers to the total number introduced 

 nto the flask containing 100 c. cm. of milk. 



MICRO-ORGANISMS OF SAMPLE I. 



la. 



Morphology. Bacillus. 



Size — average diameter, .4 microns; length, .8 — l.G microns. 



Motility — motile. 



Staining — stains readily. 

 Gelatin Colony. 



Filamentous. 

 Gelatin Stab. 



Filiform, becoming arborescent at lower portions. Later, a saccate liquefaction oc- 

 curs in the upper part of streak. 

 Inclined Agar. 



It produces a glistening, heavy growth on the surface of the agar. 

 Bouillon. 



Gives rise to a turbidity with sediment at bottom and a scum on the surface. 

 Potato. 

 Milk. 



In about ten days there is a soft curd produced. See also chart combination la 

 and Ij. 

 Fermentation of Sugars. (Dextrose, Lactose, Saccharose). No fermentation. 

 Proteolysis. 



Gelatin liquefied. Action on casein not noted. 

 Biochemical tests. 



Nitrates reduced. No iiidol, iiydrogen sulphide or uiumouia, noted. 

 Chromogenesis . 



No pigment. 



