234 LIFE IN THE INSECT WORLD. 



and hollow, and she immediately takes posses- 

 sion of it as a dwelling. Here she lays her 

 eggs, and when the young are hatched they 

 puncture the inner walls of this little cham- 

 ber in order to extract the juice. This causes 

 the gall to grow, and thus their dwelling is en- 

 larged. When one of these is broken open, it 

 is found completely filled with Aphides. 



If Renee will now take her hundred cows, or 

 as many of them as she can collect, into the 

 garden, we will look at Mary's fire-fly. 



I think we may venture to take it out of the 

 box ; we will not let it escape us yet. I was 

 speaking a while ago of the wing-cases, which 

 serve as a protection for the delicate wings un- 

 derneath. We have here an excellent example 

 of them ; they are common to the whole beetle 

 tribe. 



Mary. Is the fire-fly a beetle ? 



Aunt M. Yes, it is a small beetle. I will 

 raise one of the wing-cases a little, and let you 

 see the transparent wing. 



Mary. Yes, I see it. 



Aunt M. When the insect is at rest, they 

 are so closely folded to its body, and so com- 



