

DESCRIPTION OF CULTURES OF BACTERIA. 131 



2. Surface growth: 



Here the same applies as to the non-liquefying superficial colonies in 

 the plate. 



B. Liquefying. 



(a) Fixed form of liquefaction, if the zone of liquefaction following 

 the stab becomes larger, but assumes substantially no other form than 

 at the beginning. 



1. Tube shaped: Slowly, weak, and small. 



2. Stocking shaped: Sack-shaped, rapid, strongly, at times with 

 scalloping of the walls. 



3. Vesiculated : Babbles are formed and confined in the depth. 



(b) Variable form of liquefaction. 

 I. Initial stage: 



1. Saucer shaped. 



2. Funnel shaped. 



3. Flattened funnel shaped. 

 n. Advanced stage: 



1. Cylindrical: The liquefaction extends more above and soon 

 reaches the glass, and then extends, with a horizontal limit- 

 ing surface, downward. 



2. Funnel shaped : The liquefaction extends more uniformly 

 from the culture. The funnel shape is preserved still in 

 later stages. Often the second form is succeeded by the 

 first. 



II. Streak Cultures. 



A. Surface growth : The same designations apply as to the sur- 

 face cultures upon plates. 



B. Water of condensation. 



(a) Clear, with or without sediment. 



(6) Cloudy, with poorly defined sediment. 

 (c) Pellicle on surface. 



III. Bouillon Cultures. 



A. Fluid: 



{a) Clear. 



(b) Cloudy. 



(c) Syrupy, gelatinous. 



B. Sediment: 



(a) Cloudy. 



(b) Flocculent, if upon shaking it rises as a twisted column, and 

 can be homogeneously distributed. 



(c) Sandy, if it lies steadily at the bottom and, upon shaking, is 

 distributed as small fragments. 



IV. Potato Cultures. 



The same designations apply as to the streak and plate cultures. 



V. Plate Cultures. 



A. Without liquefaction. 

 (a) Form: 

 1. Point-like, when the dimensions are very slight. 



