DIPTERA. 



This is the order of the true flies, and the members 

 of the order are characterized by the fact that they have 

 but one pair of wings, though there are some exceptions 

 to this; there are some flies that do not have any wings, 

 and, of course, such flies do not fly — they are parasites 

 and live on some other animal as a host. After the term 

 "bug," there is no more misused term than the- name 

 "fly." Anything that looks at all like a house fly is 

 without hesitation called a fly; and nine times out of ten 

 your friend will understand perfectly when such a "fly" 

 is indicated, and will see the fly which may not be a fly 

 at all. 



The order includes some insects that pierce the epi- 

 dermis of other animals, not biting as do the beetles, but 

 piercing, much as the bugs do; while in the other and 

 much larger class of flies, the members of the different 

 families must content themselves with lapping up liquid 

 food, or rasping off small particles from some solid sub- 

 stance, these to be dissolved in the mouth fluids later and 

 swallowed in the usual way. 



Among other orders, there are numerous instances of 

 the borrowed use of the term "fly" — May fly, dragon fly, 

 gallfly, saw-fly, and butterfly — hence we see that there 

 is not much in a name anjrway. When we speak correctly 

 of flies, we mean the dipterous flies with their two wings, 

 then we use the term correctly and with accurate 

 knowledge. 



The hind wings of the flies are replaced by two queer 



183 



