CHAPTER X 



METHOD OF DESCRIBING CULTURES 

 The following method of describing cultures should 

 be carefully studied, and each suggestion should be 

 considered in the description. It is of prime importance 

 that all cultures in all media should be closely observed, 

 and accurately described and sketched, as this is the 

 only method which furnishes the proper means of study- 

 ing and determining the different species of bacteria. 

 By keeping this scheme in sight while making ?. descrip- 

 tion, it will be possible after a little practice to make 

 perfect descriptions without its aid. 



I. Morphological characters of bacterium. 

 Size. 



Facility and mode of staining. 

 Gram's stain. 

 Special staining qualities. 

 Motility. 



Present or absent. 

 Sluggish or active movement. 

 Flagella present or absent. 

 Capsules present or absent. 

 Spores present or absent. 

 Involution forms. 



Make an accurate sketch of part of a field under 

 the microscope. 

 II. Plate cultures. 



i. Naked-eye appearance. 

 a) Surface colonies. 

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