DEVELOPMENT OF THE BACTERIA. 129 



mences to move, and becomes jointed by trans- 

 verse division. 



Koch, in cultivating the bacteria of charbon in 

 aqueous humor from the eye of the ox, has ob- 

 served some facts exactly similar, both as to pro- 

 duction of spores in linear series in the filaments 

 of Bacillus anthracis and as to the germination of 

 the spore and the birth of a new rod. 



According to Van Tieghem, the development 

 of Amylobacter is as follows : " The development 

 of a Bacillus includes four successive periods. In 

 the first, the body, cylindrical and slender, recently 

 developed from a spore, stretches out rapidly, 

 and is partitioned ; the articles soon separate 

 (B. subtilis), or remain united in long filaments 

 (B. anthracis). This is the stage of growth and 

 multiplication, two things which at bottom are 

 but one. 



"Secondly, the articles previously formed, having 

 ceased to elongate and divide, increase sensibly in 

 magnitude, becoming the seat of interior chemical 

 transformations ; and this increase in size operates 

 according to circumstances, in three different man- 

 ners, with some intermediate forms. Sometimes 

 it occurs uniformly throughout the length of the 

 article, which remains cylindrical ; sometimes it is 

 localized, either at one extremity, which is swollen 

 like a tadpole, or in the middle of the article, 

 which swells to a spindle shape. This is the stage 

 of enlargement, or of nutrition, solitary and si- 

 multaneous, which prepares the following state. 



"In the third period or phase of reproduction 



