
CLASSIFICATION OF DAIRY BACTERIA. 19 
used as the foundation of my grouping that of Fliigge given 
in the last edition of his Dze MZicrobrganismen. ‘This grouping, 
as will be seen below, is based partly upon the power of pro- 
ducing pigment and partly upon morphological data. ‘This 
arrangement is quite similar to that which has been adopted 
by Fuller and Johnson, and is easily compared with that which 
has been adopted by Chester in his valuable study of the clas- 
sification of bacteria. As I have arranged these groups it 
results that in some cases there are placed together under one 
table the two genera which Migula has distinguished as Baczllus 
and Sacteritum. According to Migula’s classification a distinc- 
tion between these two genera is based upon the formation of 
spores. The genus Bacillus produces spores, while the genus 
Bacterium does not produce spores. By the method of grouping 
which I have adopted, it has resulted that in groups IV. and 
VII. both of the genera Bacillus and Bacterium are included. 
This confusion, however, is not a serious one, since it involves 
only a few organisms. ‘The grouping that has been adopted 
in the following pages is one which I have found to be the 
easiest to use in laboratory practice. The groups which I 
have recognized are as follows: 
Group I, Fluorescent bacteria, 
Il. Allred chromogentc forms. 
Ill. Ad orange chromogenic forms, 
IV. All lemon yellow chromogenic forms. 
V. All non-liquefying micrococct not included in [1,, L11., and LV. 
VI. All liquefying micrococci not included in L1,, [11,, and IV, 
VII. AW non-liquefying rods which are not chromogenic. These are 
mostly of the species Bacterium, but the table includes two of 
the genus Bacillus. 
VIII. All liguefying Bacteria without spores. 
IX. All ligquefying Bacilli with spores no larger than the rods. 
X. All liquefying Bacilli with large spores causing the rods to be 
swollen at the time of sporulation, 
NAMING THE SPECIKS. 
In regard to the question of naming the species described, I 
have been somewhat at a loss as to the best method of pro- 
cedure. Some of the species which are described are unques- 
_tionably entirely new and are very distinctly characterized. 
Others are very obscure in their diagnostic character, so much 
so that it has been difficult or impossible to give characters 
which very clearly define them. In these cases I have been 
