BACTERIUM PULLORUM INFECTION IN FOWL. 81 



From this table it will be seen that with the methods used it was not 

 possible to detect Bad. pullorum in all the dead chicks, although adult 

 hens were all positively reacting to the agglutination test. From 8, Bad. 

 pullorum was isolated without difficulty; from the other 10, the cultures 

 were negative. 



After three months, following out three sets of incubation, the author 

 was able to obtain from the three sets of eggs set, 60 in each lot, all from 

 positively reacting hens, 7 livable chicks on the first set, 9 on the second 

 set, and 9 on the third set, and these chicks were all given the numbers 

 of the parent stock from which they came: 7811, 7895, 7925, 7997, 7998, 

 8001, 8002, 8020, 8082, 8084, 8094, 8139, 8171, 8180, 8202, 8204, 8294, 

 8384, 8388, 8389, 8430, 8431, 8544, 8565, 8810. These 25 birds, all reared 

 from positively agglutinating hens, were yarded together and blood taken 

 at various times to determine whether their blood would show any signs 

 of agglutinative powers. 



When the chicks had grown to a weight of at least 400 grams, they were 

 put together in the yard on Aug. 10, 1917. The following table shows 

 the weight of each bird at that time : — 



Agglutination tests were run on these birds, the first being on July 17, 

 1917. The following table shows the reactions for this and' subsequent 



tests: — 



