16 STORRS AGRICULTURAL EXPERIMENT STATION. 
many of these descriptions nonessential features are given with 
great detail, and the whole becomes immensely confusing. It 
has seemed to me that the method adopted by Fuller and 
Johnson in a recent publication on water bacteria* marks a 
very decided advance in our method of arranging the charac- 
teristics of bacteria. [hey have devised a scheme whereby all 
of the important characteristics of a given species of bacteria 
may be briefly indicated by positive or negative signs, so that, 
by the proper arrangement of tables, it is possible by the use 
of a few of these signs to give in a very brief compass all of 
the important characteristics of the organisms to be described. 
The advantages of this scheme are manifold. In the first place 
it avoids the needless confusion of details which is so likely to 
arise from the verbose descriptions which may be given. In 
the second place it makes possible a direct comparison of species 
with each other,-and enables one to determine at a glance 
whether two forms are in agreement so far as regards their 
chief characteristics. If then further details be given else- 
where, with more careful descriptions, the task of determining 
whether a new variety is identical with one aiready described is 
an easy one. ‘The success of this method as applied to water 
bacteria has led me to adopt the same in the description and 
classification of the dairy bacteria, and the tables in the follow- 
ing pages are therefore based upon the same principle as those 
which have been used by Fuller and Johnson in their classifi- 
cation of water bacteria. | 
In these tables, however, I have found it necessary to adapt 
the plan to the descriptions which I have in my possession, 
and consequently to change the character of the table some- 
what. In the study of dairy bacteria certain characteristics 
have been inevitably regarded as of more importance than 
others; and in the descriptions of the bacteria which I have 
been accumulating some factors, particularly those in connec- 
tion with the action of the bacteria upon milk, have been 
studied in more detail than would be possible to indicate in 
the table of Fuller and Johnson. On the other hand, some of 
the characteristics which they have included in the study of 
water bacteria have not been determined at all, or only inci- 
dentally, in the case of the bacteria studied here. ‘This is to 
be regretted, since it is eminently desirable that the different 

* Jour. of Exp. Med., 1899. 

