PROBOSCIS OF ASILUS. 73 



you require a quarter-inch glass to see this well. The 

 ligula is shaped like a spear-head. The stiff horny labium is 

 pointed like a needle. When the Gnat pierces the skin, the 

 two serrated mandibles work rapidly up and down, the sheath 

 folds backward, the pressure of the lancets causes a little 

 poison-bag, situated at the base of the proboscis, to emit 

 one drop of acrid matter, and when the little creature has 

 sucked our life-blood, and her small body is distended and 

 crimsoned with her draught, she flies off like a winged ruby 

 in the sunlight, that little poison-drop rankling in the wound 

 and causing our after uneasiness and irritation. It is worth 

 the slight annoyance, however, to watch the process of her 

 feast. With a pocket lens we can see the working down 

 of the. lancets, and the up-flowing of the blood into her 

 stomach. 



The shrill buzz of the Gnat, like a fairy clarion, is pecu- 

 liar to the female, and only heard when she is bloodthirsty. 

 Her delicate wings then vibrate 3000 times -in a second, 

 and are supposed to cause this sound by the friction of their 

 bases against her body. Her eyesy which quite cover her 

 head, and the long fourteen- jointed antennae waving to and 

 fro, make her a beautiful object, in spite of her unpleasant 

 propensities. 



PROBOSCIS OF ASILUS. 



The Asilus is one of the Diptera (Flies) the largest and 

 fiercest of them most frequent in sandy situations. They 

 flit about in the hot sunshine, pouncing upon all smaller 

 flies Beetles and Hymenoptera, Ichneumon flies, &c. 

 holding them between their fore legs, and plunging their 

 sharp lancets and fleshy tongue into the softest part of their 

 prey. The colour of these flies is mostly tawny, gold- 

 coloured, or reddish-yellow ; the wings finely-veined and 

 clouded at the edge ; the body long and narrow. The 

 larva lives in the earth: it has twelve segments, and 

 changes to a spiny pupa, from whence the My emerges in 

 June. 



