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NORTH AMERICAN DIPTERA 



Family Sciaridae — The Dark Winged Fungus Gnats 



Sciara ci", 



Usually small, blackish, brownish or testaceous species, the abdomen 

 cylindrical and tapering, especially in the females. 



The insects belonging to this family are related to the Myceto- 

 philidffi, with which they have, until recently, been united. They differ 

 in having the eyes produced toward each other above the antennae, 

 instead of being regularly convex in outline, and in having shorter 

 coxge. As a general rule the wing venation is typical although a very 

 few genera of the Mycetophilidge have similar venation. 



The adults inhabit moist places or any place where fungus growth 

 occurs, particularly manure. The larva frequently become pests in 

 mushroom cellars, feeding upon the mycelium of the fungi. The females 

 are difficult to determine, the classification being based mainly on the 

 male genitalia although the ovipositors of the females also offer good 

 characters. The larvae, like those of the Mycetophilidse, have some very 

 interesting habits, some of them sometimes travelling over the ground 

 in snake-like masses. The family is treated by Johannsen in the refer- 

 ence given under the Mycetophilidae. 



