42 



MASS. EXPERIMENT STATION BULLETIN 273 



in our h.ands. 



Chicken V 2230. — At necropsy, the general condition was good. The 

 face was pale and the comb cyanotic. Pseiidoinenibrane was found in the 

 larynx, the trachea was inflamed, and congestion was noticed in tlie 

 lungs, but no evidence of consolidation could be found. The kidneys 

 Mere swollen and the tubular areas were hemorrhagic. 



V 2230 culminated one month and twenty-five days of successful trans- 

 mission of the California virus in the laboratory without loss of viridence. 

 The average period of incubation in these chickens was five days, the 

 longest seven days, and the shortest three days. The average fatal course 

 ;;fter inoculation with the first California virus was 7.-57 days, the longest 

 10 days, and the shortest 5 days. 



Continuous Passage of the Second California Virus 



Tiie second California virus was jiropagated at the same time as the 

 first virus. The results were nearly alike and the data for the second 

 virus are given in Table 12. 



Tahli; 12. — Transfers of second California virt's. 



The second California virus was transmitted in series, through seven 

 chickens from one to three months of age, covering a period of one 

 month and eight days, without losing in virulence. The average fata! 

 course after inoculation with the second California virus was 4.71 days; 

 the shortest, 3 days; and the longest, 8 days. 



The Immunological Specificity of Infectious Trachitis 



On June 23, 1!»30, two chickens, si.\ fowls, seven pullets, and seven 

 cockerels which had survived inoculations of Granby, Gardner, Westwood, 

 lladley. South Lincoln, and Watertown strains, were inoculated intra- 

 tracheally with California virus from \' 2207. Tlie results of this exjieri- 

 ment are reported in Table 13. 



In view of the great variation in immunity among the strains of in- 

 fectious trachitis used in this exjieriment, it can not be stated that the im- 

 munity produced by any strain is specific for the California virus. How- 



