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 
9 
