MORPHOLOGY AND CLASSIFICATION 149 



or larger granules, sometimes distributed pretty generally and 

 sometimes collected together at one or more places in the elL 

 The Romanowsky stain and its modifica- 

 tions have been especially useful in differ- 

 entiation of chromatin from cytoplasm. 



Special movements of the internal 

 granules have been described by Schau- 

 dinn as being associated with beginning 



cell division. For the great majority of FIG. 69. The formation of 

 ,-, , spores. (After Fischer from 



bacteria these have not been observed, f rost an d McCampbdl.) 



and according to our knowledge, the 



process of cell division is extremely simple. It consists of a pro- 

 gressive constriction and thinning of the cell at the middle until 



FIG. 70. Bacteria with spores. 



two cells are produced. In some forms the division is completed 

 by a sudden snapping movement. 



The formation of an endospore begins with the accumulation 



o C 



n 

 u 



d 



FIG. 71. Germination of spores, a, Direct conversion of a spore into a bacillus 

 without the shedding of a spore- wall (B. leptosporus); b, polar germination of B. 

 anthracis, c, equatorial germination of B. subtilis; d, same of B. megatherium; , 

 same with "horse-shoe" presentation. (After Novy.) 



of chromatin granules in one part of the cell, where they coalesce, 

 lose their contained water and seem to become embedded in an oily 



