1912.] Ducks to T. gallinarum and T. gambiense. 383 



"No connection between the fowl-parasite and that of the Simulid has 

 been as yet established, but from the habits of the fly it is highly probable 

 that it might play some part in the transmission of the trypanosome in 

 question. — Muriel Kobertson." 



Are Ducks capable of Acting as a Reservoir of T. gambiense ? 



These experiments were undertaken on the same lines as those carried out 

 by the 1908 to 1910 Commission witli the Uganda fowl. It seems possible 

 that ducks might react differently to T. gambiense, and throw some light on 

 the part played by the enormous numbers of aquatic birds along the shores 

 of Victoria Nyanza in relation to Sleeping Sickness. 



Two Muscovite ducks were obtained from Mr. Walsh's farm, as wild birds 

 were not procurable alive. The method of procedure followed consisted in 

 first feeding laboratory- bred flies upon the ducks to ascertain whether the 

 latter harboured any natural infection. The birds were then fed upon by 

 infected flies and afterwards again tested with clean flies, and finally by 

 blood inoculation into a susceptible animal. The blood was also examined 

 from time to time microscopically. 



Are the newly arrived Ducks capable of Infecting Laboratory-bred Flies with 

 Flagellates. 



Experiment 153. — From June 16 to 20, 1911, 45 clean laboratory-bred flies 

 were fed upon the two ducks, two days on each bird. The flies were then 

 fed for 27 days on a clean monkey and finally dissected. No flagellated flies 

 were found. 



Table III. 



Expt. 

 No. 



Period for which 

 flies fed upon 

 Duck 144. 



Number of flies. 



Length of 

 days. 



Eesult. 



1st day. 



30th day. 



Dissected. 



Containing 

 flagellates. 



193 

 236 

 299 

 594 



July 10—17, 1911 

 Aug. 1—3, 1911 ... 

 Aug. 16—19, 1911 

 Jan. 1—16, 1912 ... 



64* 

 81* 

 89* 

 111* 



54 

 63 

 82 

 53 



64 

 81 



111 





 

 

 



50 

 36 

 42 



32 





Totals 345 



252 



345 



| 





* Fed upon clean monkey throughout the experiment. 

 Remarks. — All these experiments proved negative, no flagellates being found in the dissected 

 flies. 



