SPORULATION . 15 



The spore is developed in the bacterial cell as follows: If 

 the organism is a mobile one it becomes quiet before sporulation, 

 during which the flagella are retained. The position of the 

 spore is early marked by a granularity of the bacterial body at 

 one point, an area soon assuming a clear glistening character, 

 often with a double contour, which may or may not increase the 

 thickness of the cell. If unfavorable conditions continue the 

 cell body disintegrates and disappears leaving the spore bare. 



?IG. 12. Capsules. Bad. pneumonia (Friedlander;. (After Weichselbaum 

 from Frost and McCampbell.) 



Certain spore bearing bacteria grown for a week at 42C. lose 

 the power to form spores; likewise their progeny. As a rule the 

 anthrax bacillus does not form spores in the bodies of animals. 

 Free oxygen is required for sporulation by some bacteria. One 

 spore only is produced by an adult cell. Some forms of bacteria 

 can be differentiated from each other only by the way in which 

 they sporulate, whether from the poles or the equator. 



Spores are formed chiefly by the rod-shaped bacteria especially 

 the anaerobic and saprophytic organisms and these varieties 

 always have a high thermal death-point. Certain round bodies 



