- , 



FIG. 60. A SATISFACTORY PREPARATION FOR COUNTING A BACTERIAL VACCINE. 

 The microorganisms are well separated and evenly distributed among; the cor- 

 puscles; the spread is even and regular, and the corpuscles are not gathered in 

 rouleau formation or irregular clumps. 



FIG. 61. AN UNSATISFACTORY PREPARATION FOR COUNTING A BACTERIAL VACCINE. 

 The microorganisms are mostly gathered in irregular masses instead of being 

 separated and evenly distributed; the corpuscles are not separated and evenly dis- 

 tributed, but show a tendency to gather in clumps; both factors render a count 

 difficult, inaccurate, and unsatisfactory 



