Microbic Diseases Individually Considered. 319 



insertion. Dermic insertion gives uncertain results, 

 the virulent Kiatter requiring to be brought into the 

 cellular tissue in order to act efficaciously. On the 

 other hand, hypodermic injection supplies the best 

 conditions for the evolution of the virus. For the 

 reception of the pulmonary serosity the cellular tis- 

 sue of the tail should be selected in preference to all 

 other regions; as has already been said the conse- 

 quences of inoculation are often very severe in regions 

 where the connective tissue is loose and abundant. 

 In the tissue of the tail, one or two drops of the 

 serosity are sufficient. It is well to make a second 

 vaccination a few weeks later ; this may be made in 

 an interdicted region although this procedure can not 

 be recommended, especially when the reaction to the 

 first inoculation has been insufficient. 



With the view of obviating the accidents which 

 occasionally follow the caudal inoculation some ex- 

 perimenters, including Professor-Director Degive, 

 have had recourse to intravenous injection ; this 

 method procures a solid immunity, but requires special 

 care in order to avoid accidental contact of the virus 

 with the cellular tissue which surrounds the vein, an 

 accident which may result in a serious, perhaps fatal, 

 eno:orgement. Larger doses may be introduced into 

 the veins than into the cellular tissue. 



For the practice of Willemsian inoculation it is 

 essential that fresh virus be employed. This is ob- 

 tained by making a clean incision of a diseased lung 

 with an aseptic knife and collecting the serosity 

 which flows spontaneously from regions in which the 

 inflammation is most recent. As such a lung is not al- 



