382 Col. Sir D. Bruce and others. [Apr. 18, 



Experiment 997. 





Day 





Eesult. 





Date. 



of experi- 

 ment. 



Procedure. 







Remarks. 









1909. 













June 15—18 



1—3 



Flies fed on infected 



goat 







60 flies used. 



„ 19—20 



4—5 



Flies starved. 









„ 21— 



6—18 



Flies fed on healthy 



+ 







July 3 





calf, 1030 







July 6, injected in- 



July 4—5 



19—20 



Flies starved. 







fected fly into goat ; 



„ 6-21 



21—36 



Flies fed on healthy 

 bull, 1268 



-1- 





negative. 

 Aug. 10, remaining 



„ 22—23 



37—38 



Flies starved. 







flies dissected. In- 



„ 24- 



39-56 



Flies fed on healthy 



+ 





fected fly injected 



Aug. 10 





calf, 737 







into goat ; negative. 



Remarks. — Sixty wild flies were fed for four days on a goat infected with Trypanosoma 

 vivax. Eleven days after their first feed they became infective, and remained so during 

 the experiment. Two flies were found infected with flagellates, one on the 21st day, and 

 one on the 56th day, both of which when injedted into goats failed to give rise to the 

 disease. 



Experiment 998. 



Date. 



Day 

 of experi. 

 nieut. 



Procedure. 



Eesult. 



Remarks. 



Positive. 



Negative. 



1909. 

 June 15—18 



„ 19—20 

 „ 21- 

 July 3 

 July 4 — 5 

 „■ 6- 

 Aug. 5 



1—3 



4—5 

 6—18 



19—20 

 21—51 



Flies fed on infected 



goat 

 Flies starved. 

 Flics fed on healthy 



calf, 1030 

 Flics starved 

 Flies fed on healthy 



calf, 1267 



+ 

 + 





45 flies used. 



Aug. 6, pooled con- 

 tents of 14 flies re- 

 niainiug ; injected 

 into goat, which be- 

 came infected with 

 T. vivax. 



Remarks. — Forty-five wild flies were fed for four days on an infected goat. Eleven 

 days after tlieir first feed they became infective, and remained so during tlie experiment. 

 The pooled contents of the 14 remaining flies injected into a goat on the fifty-second day 

 gave rise to infection with Trypanosoma vivax. 



