BIONOMICS OF GLOSSINA BEEVIPALPIS. 93 



at about 5.0 p. 



fliorrino' 



attempts to find the pupae of this fly by 

 round the bases of various trees were however un- 

 successful. Davey states that about 4.0 p.m. G. hrevijyaJpis " seems 

 to emerge from its hiding place and settle on dried leaves, sticks 

 or dust on paths, apparently lying in wait for a meal " : the same 

 writer adds that he has noticed that " game, on its way to water 

 in the evening, often stands for a time on emerging from the 



Fig. 22. 

 A Tsetse-fly (Glossina morsitans, Westw., 9 ), before feeding, (x 6.) 



forest on to a path, and would thus afford the fly an opportunity 

 for feeding." According to Davey, G. brevipalpis as a rule 

 " seems ready to bite human beings in the evening, but it does 

 not set to work with the rapidity and voracity that G. morsitans 

 often exhibits." When feeding captive flies, Stuhlmann finds 



f is. 23. 



A Tsetse-fly (Glossina morsitans, Westw., $), after feeding, showing abdomen distended 

 with blood. (x6.) From a drawing from life, kindly lent by Colonel Sir David 

 Bruce, C.B., F.R.S., A. M.S. 



that the insects generally wait for a while before deciding to 

 suck ; they then, however, drive in the proboscis with great 

 quickness, and the abdomen usually becomes swollen out like a 

 balloon with blood in from thirty to forty seconds. In captivity 

 flies of this species show very little inclination to feed in very 

 hot and sultry weather, and this is also the case when the 



