THE DESCRIPTIVE CHART 101 
campesiris group. For each strain the same group number was obtained 
which would indicated that it was well fitted to these bacteria. This 
author believes that it may not “carry the separation to a group 
synonymous with the ordinary conception of species.” This statement 
seems to have been borne out by later investigations. Harding and 
Prucha (1908) used the Descriptive Chart in the study of bacteria 
from cheddar cheese. In their conclusions, they state that this method 
of recording the reaction of cultures is a marked advance in technique, 
and that shifts in the cheese flora may be thus traced more accurately. 
The sum and substance of their opinion of the Chart in its application 
to the study of cheese bacteria is that it is a valuable means to an end. 
Harding, Morse and Jones (1909) in their study of soft rot organisms 
used the group number. By examining their data it is apparent that 
the group number is a valuable aid. Harding reached essentially the 
same conclusion in 1910 when he studied the same group of bacteria. 
Conn (1906) when classifying dairy bacteria drew no conclusions with 
regard to the value of the rudimentary group number which he used. 
More recently H. J. Conn (1915) reported the study of 130 strains of 
B. subtehs by means of the Descriptive Chart. In selecting these 
strains one-half of the determinations represented in the group number 
are fulfilled because they were implied in the definition of B. subizlis. 
He stated that different group numbers did not always represent dif- 
ferent species, and that better methods for making these ten deter- 
minations should be devised. This worker later used the Descriptive 
Chart in another investigation involving the study of about 1000 pure 
strains isolated from soil (Conn, 1917). The Chart was found to be 
quite well adapted to the study of spore forms and was of value in the 
‘preliminary study of other forms before learning what special tests 
were best adapted to them.” The following tests were reported to 
give sufficiently consistent results to be of diagnostic value: shape of 
vegetative forms, size of vegetative forms, arrangement of flagella 
when present, presence of spores, size and shape of spores, growth in 
the absence of oxygen liquefaction of gelatin, nitrate reduction, chromo- 
genesis and form of growth in liquid and solid media. At times some 
of these gave inconsistent results. Edson and Carpenter (1912) made 
no statement in their study on sap bacteria about the value of the 
Descriptive Chart. Tanner (1918) used the Chart in the study of 
green fluorescent bacteria from water and found the Chart a very 
convenient method for carrying out such a study. 
Description of Microorganisms. The Descriptive Chart of the 
Society of American Bacteriologists has been given rather extended 
