72 FRED W. TANNER 



state of Illinois. It was decided to limit this study to the forms 

 obtained from water, and at a later date, if possible, to study 

 another series from a different source. The investigation by 

 Edson and Carpenter was made with strains many of which 

 came from the same sap orchard. In this way their strains 

 may have had some close relationship. The strains which 

 form the basis of the present study are probably in no way 

 related. The source of these strains is given in table 2. 



TABLE 2 



Surface waters 35 



Shallow wells (under 100 feet in depth) 50 



Deep wells (over 100 feet in depth) 3 



Springs 4 



Cisterns 3 



Swimming pool 1 



Sewage 1 



Water of unknown source 1 



Water from interstate carrier 1 



Ice 1 



The colonies were picked from agar and gelatin plates which 

 had been made from water samples received at the laboratory 

 of the Illinois State Water Survey. All of these samples were 

 collected according to instructions which were furnished with 

 the sterile container. They were shipped to the laboratory 

 packed in ice, the examination was immediately started on 

 receipt of the sample and after the plates had been counted for 

 the routine analysis, they were examined for fluorescent bac- 

 teria. If none were evident, it was found that they often ap- 

 peared after the plates had been held at room temperature over 

 night. Young strains were used in all cases. All inoculations 

 into the various media were made either from a twenty-four 

 hour broth culture or from a twenty-four hour agar slant 

 culture. 



Description of strains 



Since the Society's chart was used in this study the various 

 cultural and morphological characteristics will be mentioned in 

 somewhat the order in which they appear on the chart. 



