V. Family CHIRONOMIDjE. 



Gnatlike flies of slender form, seldom reaching ten mil- 

 limeters in length; the males conspicuous for their plu- 

 mose antennae. Head small, spheroidal, more or less 

 concealed by a projecting, hoodlike thorax. Antenna; 

 threadlike or beadlike with not less than six nor more 

 than fifteen joints; in the male usually with a long dense 

 plumosity; in the female with inconspicuous hairs and 

 sometimes with a smaller number of joints; the first joint 

 short and thick. Eyes reniform or oval; ocelli wanting 

 or rudimentary; proboscis short; palpi three or four- 

 jointed; the last usually elongated. Thorax ovate, very 

 convex, usually projecting above in front more or less 

 over the head; without transverse suture; scutellum 

 small, hemispherical. Abdomen usually narrow and 

 long, composed of eight segments; hypopygium project- 

 ing forcep-like ; ovipositor very short, but little devel- 

 oped ; legs usually slender and long ; especially the front 

 pair; coxae of moderate length. Tarsi often much elon- 

 gated. Wings narrow and long; bare or uniformly hairy; 

 anterior veins stronger and darker colored than the others; 

 auxiliary vein complete, but usually very weak and slen- 

 der; second longitudinal vein usually wanting; third 

 vein sometimes forked close to its origin, the upper branch 

 often rectangular and having the appearance of a super- 

 numerary cross-vein ; fourth vein often, the fifth usually, 

 furcate; posterior cross-vein often wanting; the costal 

 vein terminates near the tip of the wing at the termina- 

 tion of the third vein. 



This family comprises a large number of very delicate, 

 often minute flies, commonly known as midges, which 



no 



