Pleuro-Pneumonia of Cattle. 



175 



tion. Samples of serum were then kept in the ice-chest for use 

 as required. For use they were further diluted, if necessary, 

 with saline solution immediately prior to being used in the tests 

 until the required dilution was obtained. A complete list of the 

 serum samples obtained is as follows: — 



Serum 



Source. 



Positive or 





Sample No. 



Negative. 





1 



Natural Infection 



Positive. 





2 



Natural Infection 



Positive. 





3 



Natural Infection 



Positive. 





4 



Natural Infection 



Positive. 





5 



Natural Infection 



Positive. 





6 - 



Natural Infection 



Positive. 





7 



Institute Cow No. 36 



Negative. 





■8 



Natural Infection 



Positive. 





9 



Direct contact with in- 



Inoculated 



with virus in the tail 



- 



fected animals 



and reacted. No. C.P.P. on 







P.M. 





10 



Direct contact with in- 



Inoculated 



with virus in the tail 



- 



fected animals 



and reacted. No C.P.P. on 







P.M. 





11 



Natural Infection 



Positive. 





12 



Natural Infection 



Positive. 





13 



Natural Infection 



Positive. 





14 



Natural Infection - 



Positive. 





15 



Natural Infection 



Positive. 





16 



Natural Infection 



Positive. 





17 



Experimental Cow No. 2 







- 



(before inoculation) 



Negative. 





18 



Natural Infection 



Positive. 





19 



Institute Cow No. 37 



Negative. 





20 



Direct contact with in- 



Inoculated 



with virus in tail and 



- 



fected animals 



reacted. 



No C.P.P. on P.M. 



.21 



Direct contact with in- 



Inoculated 



with virus in tail and 



- 



fected animals 



reacted. 



No C.P.P. on P.M. 



22 



Direct contact with in- 



Inoculated 



with virus in tail and 



- 



fected animals 



reacted. 



No C.P.P. on P.M. 



23 



Natural Infection 



Positive. 





24 



Natural Infection - - 



Positive. 





25 



Natural Infection 



Positive. 





26 



Natural Infection 



Positive. 





.27 



Natural Infection 



Positive. 





28 



Natural Infection 



Positive. 





29 



Experimental Cow No. 4 - 



Reacted to inoculation behind 







shoulder. 





.30 



Calf No. 1 -'. - - 



Immunised 



by an inoculation in 







the tail, 



followed by inocula- 







tions beh 



ind the shoulder. 



31 



Institute Cow No. 35 



Negative. 





J2 



Calf No. 2 



Immunised 



by an injection in the 







tail, followed by inoculations 







behind the shoulder. 



