PARTS OF AN INSECT. 



55 



The mouth is on the under side of the head, and is sur- 

 rounded by certain parts called mouth-parts. These parts 

 differ greatly in different insects. 



52. In those insects that chew their food, such as the bee- 

 tles and grasshoppers, certain of the mouth-parts act as teeth, 

 or jaws, and, being joined to the right and left sides of the 

 mouth, move sideways, and not up and down, as in other 

 animals. In other insects some of the mouth-parts are very- 

 long and slender, so as to form a long, sharp sting, as in the 

 bugs proper, so that they use them to suck the juices of 

 plants upon which they feed. Or, the parts are again modi- 

 fied in shape to form a long, slender tube, by which the 

 nectar of flowers may be sucked, as in the butterflies. 



antenna. 



mouth-parts. 



antenna. 



mouth-parts.^ 



antenna. 



BUG. 



mouth-parts. 



antenna. 

 BEETLE. 



mouth-parts. \ 



MOTH. 



FLY. 



FIG. 55. SHOWING MOTJTH-PARTS OP A FEW INSECTS. THE HEADS ARE SEPARATED FROM 

 THE BODIES, AND ARE FACING THE LEFT, AND DRAWN IN PROFILE AS SEEN FROM THEIR 

 LEFT SIDES. 



In the common house-fly, the mouth-parts appear as a 

 proboscis, a kind of fleshy appendage which is bent up when 

 not in use. "When the fly feeds, the proboscis unbends, and 



