472 THIRD PART.—BACTERIA OR SCHIZOMYCETES. 
and these break up into fragments containing from two to several coils and 
exhibiting active movement; they were formerly known by the name of Ophidomonas, 
and are said to have a long oscillating cilium at each extremity (Fig. 198 £). 
The same states have been observed in Beggiatoa roseo-persicina as in B. 
alba; the net-like zoogloea-form, once known as Clathrocystis, is a peculiar and 
remarkable feature in this species. 
Cladothrix and Leptothrix buccalis of tooth-caries resemble each other in 
their development. Further details 
will be found in Zopf’s descriptions. 
The Fungi of mother of vinegar, 
Arthrobacterium aceti and A. 
Pastorianum (Hansen), must also 
be placed in the arthrosporous group. 
They are distinguished it is true, as 
Hansen has observed, by the occur- 
rence of many large vesicular cells 
between the small cocci or rod-cells 
of a chain, and the almost constant 
appearance of these cells at once 
suggests that they are connected with 
some process of spore-formation. 
But the observations afford no distinct 
support to this view, and the phe- 
nomenon must for the present be 
classed with those of involution 
which were mentioned on a former 
page. The Micrococcus also of 
Pasteur’s fowl-cholera may also be- 
long to this group}. 
Section CXXXII. The fore- 
going review of the Bacteria will 
supply us with some safe means of 
determining the question of the 
FIG. 198. Beggratoa alba. Curved and spiral forms. 4 group of specific value of observed. forms, 
attached filaments. 3—H portions of spiral filaments; C, D, F—H in a question which is at pr esent th e 
the act of dividing into smaller fr and without movement; 7 
(Spiros )Peitha ciumar each end, The suiphurgranuleshere asin SUDJect Of much discussion and which 
Fig. 197. After Zopf. Magn. 540 times. must not therefore be ignored in 
this place. 
There are two views on this subject which appear at least to be diametrically 
opposed to one another. One of these is, as it seems to me, incorrectly ascribed to 
Cohn, and maintains that every Bacterium which occurs in the same growth-form 
and produces the same effects of decomposition, though this latter point does not 
strictly fall within our limits, represents a species in the sense in which the word 





1 Pasteur in Comptes rendus, 90 (1880), pp. 239, 952, 1030, and 92 (1881), p. 430. 
