13 



generally be relied on to stimulate them to a special effort. In 

 the act of biting the tail end is raised so that the line of thorax 

 and abdomen makes an angle of forty-five degrees or so with the 

 horizontal ; the abdomen becomes very much distended with blood 

 and except at the extreme tip assumes a transparent red colour : 

 as digestion proceeds this red colour darkens and after about five 

 hours the abdomen appears black ; after sixteen hours half the 

 abdomen has been emptied of its contents, while after thirty-six 

 to forty hours the whole meal has been digested and got rid of. 

 When first gorged with blood the insects fly with difficulty, and 

 prefer to sit quietly digesting : they are then easily seen, and can 

 sometimes be caught in the morning sitting inside the mosquito- 

 net." As to the parts most usually attacked by these flies, it was 

 noticed by Doerr in Herzegovina that Phlebotomus papatasii shows 

 a preference for particular regions of the body, " especially the 

 ankles, upper part of the feet, wrists and forearms, particularly the 

 flexor surfaces ; the bend of the knees, legs, upper arms, and neck 

 are more rarely bitten, and the face, back of the neck, back, and 

 thighs are generally spared, even in the case of men lying naked."* 

 With reference to the effects produced by the bite of Phlebotomus 

 papatasii, Doerr writesf : " The bites of Mosquitoes are more 

 easily endurable than those of ' Pappatacis ' [Ph. papatasii], 

 which are so painful that the person bitten immediately awakes. 

 The flies exhibit a preference for certain individuals, who are 

 tormented every night, get no sleep until about 5.0 a.m., show a 

 strong reaction with vesicular swellings, oedema, and lymphangitis, 

 suffer frightfully from itching, and look as though they had prurigo, 

 or a peculiar, papular exanthem." The same author adds that 

 in Herzegovina many of the Austro-Hungarian soldiers, who 

 suffer severely from the attacks of these flies, " prefer sleeping in 

 the open on warm summer nights to passing the night in rooms 

 full of Pappatacis." 



At the present time our knowledge of the 



Life-history, life-history of Phlebotomus is mainly due to the 



celebrated Italian zoologist Professor Battista 



* Doerr, Op. cit., p. 113. f Op. cit., pp. 161 162. 



