44 MORPHOLOGY OF THE BACTERIA. 
new individuals, which sometimes become sepa- 
rated completely the one from the other, to form 
unicellular bacteria, sometimes remain united; and 
segmentation again occurring in each portion, a 
chain is formed of articles more or less numerous. 
When these chains are formed of spherical bac- 
teria, they have been called torule; if they are 
formed of filiform bacteria, they correspond to 
leptothriz (Robin). The morphological difference 
between the torula and the leptothrix consists in 
the fact that in the first the articles are separated 
by constrictions, while this is not the case in the 
second. It is also to be remarked, according to 
Cohn, that the microbacteria never take either 
of these forms. Warming states, however, that 
he has met the torula form in Bacterium lineola, 
B. catenula, and B. termo (2). 
Billroth has called these two forms of bacteria 
streptococcos and streptobacteria. He has even 
considered it necessary to create the words diplo- 
coccos and diplobacteria for organisms constituted 
only of two articles. 
2. Form of Zooglea.— Generally, when bacte- 
ria are rapidly multiplying, they remain grouped 
in masses, swarms, or Zooglea. In the latter con- 
dition, they are closely pressed against each other 
in the midst of a viscous substance, hyaline, ho- 
mogeneous, colorless, and constituting masses 
more or less diffused or definite, in irregular 
globes, bunches, or tubes, swimming in the water 
or near its surface. When the bacteria multiply 
abundantly, the cells become removed from each 
