512 THE BACTERIOPHAGE AND ITS BEHAVIOR 



Barnyard 6. The epizootic began on December 16. On the 28th, 

 40 of 142 fowls had died. The 102 survivors, of which 3 were infected, 

 were inoculated. The sick recovered and the disease abruptly stopped. 



Barnyard 7. The epizootic began on January 2. By January 14, 

 15 of 50 animals had died. The 35 survivors were inoculated. No 

 new cases developed from this time on. 



Barnyard 8. The epizootic began about January 15 with a daily 

 mortahty of 4 to 6 fowls. On January 21 the 121 survivors, including 

 5 which were sick, were inoculated. The sick recovered and the 

 epizootic stopped at once. 



Barnyard 9. The epizootic began about February 10. By Feb- 

 ruary 20, 14 chickens had died from among the original 84. The 

 70 survivors were inoculated and the disease disappeared at once. 



Barnyard 10. The epizootic began about February 25. By March 

 1, 20 chickens had died. The 120 survivors, of which 5 were sick, were 

 inoculated. The 5 recovered and the epizootic stopped. 



Barnyard 11. The epizootic began on February 4. From February 

 4 to 10, 10 chickens died. On February 10 the 48 hving fowls were 

 inoculated in the wing with 0.5 cc. of the Galhnarum-bacteriophage, 

 as had been all the chickens in the ten preceding experiments. The 

 epizootic continued its course and 5 chickens died from February 10 

 to 17. On February 17 the 43 fowls which remained were inoculated 

 with 0.5 cc. of a mixture of four races of the bacteriophage: active 

 against B. gallinarum, B. pullorum, A, B. pullorum B, and B. pfaffi. 

 The epizootic stopped immediately after this second inoculation. 



Barnyard 12. This barnyard was adjacent to the preceding and 

 here the same facts were observed. A first inoculation made on Feb- 

 ruary 9 on 80 chickens with a suspension of the Gallinarum-bacterio- 

 phage was without effect. The epizootic stopped abruptly after an 

 inoculation of bacteriophage active for the bacillary agents of the 

 paratyphoses, made on February 17. 



Examination of the blood of fowls dead in Barnyard No. 12 resulted 

 in the isolation of a B. pfaffi, type of bacillus. This organism, then, 

 was responsible for the epizootics in groups 11 and 12. In this con- 

 nection I will only mention the instance of the epizootic of paratyphosis 

 at Trainel mentioned elsewhere. This outbreak was Ukewise due to 

 B. pfaffi and was controlled by the inoculation of a Pfaffi-bacteriophage. 



Experiment II. This was performed at Foully en Auxois with the 

 assistance of MM. Voillot and Bouhier, D.V.M. 



Barnyard 1. On January 5, 20 chickens were taken at random from 



