SOO DIPTERA. 
resembles it so much in its general ap- 
pearance, that it might be taken for 
one, unless the observer were near 
enough to distinguish that it has but two 
wings. 
Jjucy^ Does it sting very severely, like 
the bee ? 
Mother. It cannot be said to sting, as 
its attacks are not made with that de- 
sign ; its sole purpose is to lay its eggs. 
Lucy, That is like the ichneumon, 
which gives the wretched caterpillar so 
much pain. 
Mother, The instrument, with which the 
gad fly makes an incision in the bkin of the 
animal, in order to deposit its eggs, is still 
more curiously formed than that of the 
ichneumon : it is composed of four tubes, 
one within the other, so that they push 
out like those of a pocket telescope. 
The outer tube is hard and shelly, and 
the inner one is terminated by five sharp 
points, of which three are hooked : with 
these it rapidly bores a hole through the 
roughest hide, and, guided by the tube, 
