HOW TO KNOW THE INSEQS 



midge and the Wheat midge are among the well known pests belong- 

 ing to this family. 



6b Costa ending near tip of wing 7 



7a Coxae usually much elongate (a); all the tibiae with apical 



spurs (b); ocelli usually present; rather small slender flies. 



(The Fungus Gnits.) Fig. 204. Family 16, MYCETOPHILI DAE 



Fig. 204. ^/lycetophlla punctata Melg. 



Head and thorax reddish tan, abdomen 

 darker. Wings light tan. Eyes and 

 antennae dark reddish brown. Length 

 5-6 mm. 



This Is another large family of rather 

 small somewhat mosquito-shaped files. 

 Many species feed In fungi and compete 

 with other Insects In hastily reducing 

 these plants. The long coxa Is a char- 

 acter for Identification. As with sev- 

 eral other families of Dlptera, practi- 

 cally no work has been done on the fam- 

 Figure 204. Hy in lowa. The Intensive study of one 

 of these groups would make a fine avocation as well as a valuable 

 contribution to science. 



7b Coxae not noticeably elongated; usually no apical spurs on 

 tibiae; ocelli wanting, antennae usually plume-like. (The 

 Midges.) Fig. 205. Family 9, CHIRONOMIDAE 



Fig. 205. Chlronomus lineatus Say 



Thorax very light greenish gray with 

 mid-dorsal stripe of dark brown and lat- 

 eral markings of light brown. Abdomen 

 pale green with lateral lines of pale 

 brown. Eyes dark reddish brown. Length 

 about 10 mm. 



Most of the Midges are unable to bite 

 although they loo^ much like mosquitoes. 

 The air is often filled with the adults 

 and at night they become so numerous 

 about our .lights as to drive us from our 

 work. Our water courses are filled with 

 their larvae, Yifhlch doubtless play a very 

 important part in feeding young fish. Our 

 Iowa species probably run into the hun- 

 dreds, out not a dozen have been named. 



Figure 205. 



8a Third segment of antennae with rings, often long and seeming 

 to consist of several segments 9 



8b Third segment of antennae not ringed, but bearing an elongate 

 style or arista 10 



9a Discal cell (a) small, its dimensions usually nearly equal; 

 squamae small or vestigial; no spurs on tibiae. (The Soldier 

 Fl ies.) Fig. 206. 



Fami ly 20, STRATIOMYI DAE 



99 



