130 REpoRT OF DEPARTMENT OF BACTERIOLOGY OF THE 
in the fermentative vigor of the culture, concerning the details 
of which comparatively little is known, the amount of gas 
produced fluctuates above and below this saturation point 
giving the accompanying positive and negative results based 
on the presence or absence of visible gas in the closed arm of 
the fermentation tube. 
The important fact of this fluctuation having been recog- 
nized it is a matter of little consequence to the scientist 
whether it is maintained that there are six species or only 
one. It should be mentioned in passing that the idea of 
species as originally conceived is entirely inapplicable to 
bacteria since it was based on morphological similarity 
coupled with an ability to produce fertile offspring. Mor- 
phologically the entire bacterial world can be divided into 
only a few groups and sexual reproduction is entirely lacking. 
In the present instance it seems to the authors that the only 
possible basis for recognizing more than one so-called species 
in connection with the present group of cultures must lie in 
the relation of the parasite to the host and since that part of 
the subject will be treated in a succeeding publication the 
matter of classification will be dropped at this point. 
DETAILED DESCRIPTION. 
On the Classification Card of the American Society of Bac- 
teriologists in addition to the group number and the material 
given in Table II, there is a provision for the detailed char- 
acteristics of the organism in question. It was the original 
intention to present this description for the typical repre- 
sentative of each of the groups of cultures as given above, 
but when these descriptions had been prepared it was found 
that they were practically verbatim copies with the exception 
of the fermentation of sugar which has already been dis- 
cussed. Accordingly the description of Bacillus carotovorus 
Jones will be given and with the exceptions just noted this 
may be accepted as applying to the entire collection of 
cultures. 
