DIPTERA. 



185 



elongated into slender, sharp-pointed stylets; but the 

 majority of flies, as has been said, have the mouth parts 

 adapted for lapping up liquid food much as a kitten laps 

 up milk. This lapping mechanism is a modification of the 

 under lip, a curious jointed organ which you may see a 

 house fly use if you will put a lump of sugar down on some 



FIG. 74. Various forms of antennae of flies. (Williston.} 



convenient surface and put your reading glass in position 

 to use it at a second's notice. The members of the order 

 having such mouth parts feed on the nectar of flowers, 

 on the juices of decaying animal or vegetable matter, on 

 some sweetish exposed liquid, or occasionally on some 

 solid, as a lump of sugar. In the last case the solid must 

 be rasped off, if one may so describe the act of licking the 

 solid sugar, and then conveyed to the mouth where it is 

 swallowed after solution. 



