STUDY OF BACTERIAL CULTURES 



113 



to solidify. The plate showing a small number of colonies devel- 

 oping is the one chosen for examination. The characters to be 



Fig. 60. Portion of an agar plate culture showing a mold colony and five 



bacterial colonies. 



noted are rapidity of growth, form, elevation, and edge of the colony 

 and type of liquefaction if it occurs. 



Fig. 61. Ameboid colony on an agar plate (Lewton-Brain and Deerr). 



Colonies on Agar Plates. Plates containing nutrient agar are 

 prepared in the same manner as the gelatin plates described. The 



8 



