BACILLUS COLI COMMUNIS. 457 
to the typhoid bacillus, is in all probability the typhoid 
bacillus. The same could probably be stated of a 
bacillus which grew characteristically in glucose bouil- 
lon and nutrient gelatin, and also showed the specific 
serum reaction. Probably not one time in ten thousand 
would such bacilli prove on further investigation not 
to be typhoid bacilli. A still further test is to inocu- 
late animals with several doses of the dead bacilli, 
whose identification is sought, and note whether there 
is produced a serum which agglutinates typhoid bacilli. 
