78 



A Bacterial Sjwf of CU)-tf> 



It developed 'no symptoms of illness and on 7th October, 1915, received 

 a further similar subcutaneous inoculation, the same dose being used. 

 On 11th October the rabbit showed symptoms of severe illness with 

 thick mucopurulent discharge from the eyes and extreme dullness. On 

 12th October, 1915, it was found dead, and the post mortem examina- 

 tion showed nothing but a slight hyperaemia of the lungs. Cultures 

 from the heart's blood remained sterile. This rabbit's death was 

 probably not due to the bacillus of Lemon disease as the inoculation 

 of the first rabbit (A) was a much more severe test of pathogenicity. ' 



Intravenous inoculations were not attempted as it has been found 

 that most non-pathogenic organisms will produce death from toxaemia 

 except in very small doses. 



Rabbit (A) was bled on 12th November, 1915, and its serum tested 

 for agglutinins against the organism. Agglutination was obtained in 

 a dilution of 1 — 800 distinct, and pal'tial in a dilution of 1 — 2000. The 

 serum of a normal rabbit gave no agglutination in as low a dilution as 

 1 — 10. Fresh orange juice would not agglutinate the bacillus in any 

 dilution. 



The agglutination test should prove of use in the ultimate proof 

 of organisms causing plant diseases and is quite easy to apply. 



Comparative table of characters of three organisms 

 causing diseases of Citrus. 



