472 



Mr. E. C. Hort. 



In every ease the cultures under examination successfully passed at every 

 stage the necessary standard identification tests, the final agglutination 

 results of the three strains of members of the enteric group selected for 

 demonstration being detailed below. 



Shiga-Kruse Strain. — Final culture in broth, + 10 phen. direct from 

 broth, +20 phen. Dilution of antiserum 1/10, titre 1/1500, date of tubing 

 20.9.16 (Lister Institute). 



Final dilutions ... 1/40 1/80 1/160 1/320 1/640 1/1280 1/2560. Control. 

 Result Agg. Agg. Agg. Agg. Agg. Agg. Nil. Nil. 



Incubated for two hours at 56° C, and read after 24 hours at room 

 temperature. 



B. Typhosus Strain. — Final culture in broth, +10 phen. direct from 

 broth, +60 phen. 



Dilution of antiserum 1/20, titre 1/6000, date of tubing 31.3.16 (Lister 

 Institute). 



Final dilutions ... 1/80 1/160 1/320 1/640 1/1280 1/2560 1/5120 Control. 

 Result Agg. Agg. Agg. Agg. Agg. Agg. Agg. Nil. 



Incubated for two hours at 56° C, and read after one hour at room 

 temperature. 



B. " Y" of Hiss. — Final culture in broth, +10 phen. direct from broth, 

 + 20 phen. 



I Dilution of antiserum 1/10, titre 1/1500. 



Final dilutions ... 1/40 1/80 1/160 1/320 1/640 1/1280 1/2560. Control. 

 Result Agg. Agg. Agg. Agg. Agg. Agg. Nil. Nil. 



Incubated for two hours at 56° C, and read after 24 hours at room 

 temperature. 



The precautions taken against contamination are as follows, the culture 

 media employed throughout being peptone agar and peptone broth, the 

 latter +10 to phenolphthalein, +20 to phenolphthalein, and +60 to phenol- 

 phthalein, the last being only exceptionally employed. 



1. The acid broth in each case was, after tubing, autoclaved for 30 minutes 

 at 120° C. under a pressure of 20 lb. 



2. Control tubes of uninoculated acid broth were incubated at 37° C. for 

 the same length of time as the inoculated tubes. In no case was any 

 turbidity or deposit observed after prolonged incubation. 



3. In many of the cases the acid broth was contained in specially made 

 silica glass flasks, the narrow necks of which were closed with rubber teats 

 sterilised by one hour's immersion in pure lysol, and subsequently dried 

 in sterile metal boxes for 24 hours at 56° C. It this way it was possible 



