568 THE BACILLUS OF MALIGNANT (EDEMA 



ance. The inoculations are repeated every week or 10 days, gradually 

 increasing the doses inoculated to j, i and 1 drop, and inoculating each time 

 a little nearer the base of the ear. After 5 or 7 weeks the animal may be 

 inoculated with 1 drop of virulent exudate beneath the skin of the abdominal 

 wall, and the degree of immunity is increased by successive inoculations into 

 the cellular tissue of the trunk. When large doses are being administered 

 it is not uncommon to find that an abscess forms in which phagocytosis is 

 very active : these abscesses resolve. The immunity so acquired is per- 

 manent and may be transmitted from the mother to the offspring. 



It should be mentioned that Leclainche and Vallee have succeeded in 

 immunizing guinea-pigs by Aiioing's vaccination method (supra). 



4. Serum therapy. 



Leclainche obtained a very powerful serum by inoculating asses, animals 

 which are only slightly susceptible to the disease, intra-venously and then 

 intra-muscularly (into several muscles) first with the exudate and afterwards 

 with cultures grown in Martin's broth. 



This serum is powerfully antitoxic and neutralizes the toxin of the bacillus. 



A mixture of 2 c.c. of the serum with 5 drops of an exudate is harmless to 

 guinea-pigs. The animals show no degree of immunity as a result, and die 

 as quickly as the controls when tested by inoculation. The serum is without 

 action on the virus of quarter ill. 



5. Agglutination. 



Leclainche's serum agglutinates young cultures grown in Martin's broth 

 in a few minutes. This agglutination occurs in dilutions of 1 in 30 to 1 in 

 3,000 and is more marked under aerobic than under anaerobic conditions. 

 The bacillus of quarter ill is not agglutinated by a malignant oedema 

 serum. 



