306 



Dr. H. L. Duke. Antelope as a [Apr. 20, 



of this waterbuck. These will be undertaken shortly. The size of the 

 animal and its resentment of handling make the satisfactory application of 

 the fly test very difficult. 



There is, however, every reason to believe that the infected fly of Box 22 

 must have fed at least once upon this waterbuck, and the animal apparently 

 resisted re-infection. For some time past it has been suffering from an 

 injured foot, which has prevented more extensive investigations being carried 

 out. 



Duiker 648. 



Originally infected, February, 1911. Latest evidence of infectivity, April, 

 1911. 



Fly Experiments. 



1 



Number of flies. 



Length 

 of 



ment in 



Result 



of 

 feeding 



on 



monkey. 



Eemarks. 



Expt. 

 No. 



Period for which 

 flies fed upon 648. 



1st 



30th 



Dissected 

 during 



Con- 

 taining 



lates. 



16 



22 

 13 



April 24—29, 1911 

 April 25-29 „ 

 Aug. 3—4 



19 



36 

 24 

 37 



18 

 25 

 46 



1 



J 



96 

 123 

 105 





45th day fly. 

 122nd day fly. 

 Miss Robertson's experi- 





Totals 



90 



77 



89 



2 









The salivary glands of the positive fly of Experiment 16 were not observed. 

 The fly of September 22 showed a characteristic infection of gut and salivary • 

 glands. 



Injection Experiment. 





Expt. No. 



Quantity of blood injected. 



Result. 



Animal used for 



Date. 



Pure. 



Citrated. 



infection. 



6.2.12 



637 









Monkey. 



Bushbuck 2328. 



Originally infected, April, 1910. Latest evidence of infectivity obtained 

 in August, 1910, when this antelope infected laboratory-bred G. palpalis with 

 T. gambiense. 



