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AN INTRODUCTION TO ENTOMOLOGY 



Family LONCHOPTERID^ 



The Spear-winged Flies 



These are minute flies, which measure from 2 mm. to 4 mm. in 

 length, and are usually brownish or yellowish but never green nor 

 metallic in color. When at rest the wings are folded flat, one over 

 the other, on the abdomen. The apex of the wing is pointed, and the 

 wing as a whole is shaped somewhat like the head of a spear (Fig. 

 1097). This suggested the family name. 



The venation of the wings is very characteristic, and is sufficient 

 to distinguish these flies from all others. The cross-veins r-m and 

 m-cu are oblique, and near the base of the wing. Vein Cu2 is very 

 short, and extends towards the base of the wing. In the females 



Fig. 1097. — Wing oi Lonchoptera, female. 



vein Cuj coalesces with vein M3 as shown in the figure, but in the 

 males the tip of vein Cui is free. The posterior lobe is wanting. 



Three ocelli are present. The antennse are three-jointed; the 

 third segment is globular, and bears a long arista. 



These flies are common from spring till autumn, in damp grassy 

 places. They frequent the shores of shady brooks, where the atmos- 

 phere is moist. The males are very rare in this country. Professor 

 Aldrich examined over 2,000 specimens and found only two males 

 among them. 



"The larvae live under leaves and decomposed vegetable matter. 

 The larva transforms into a sort of semipupa within the last larval 

 skin, and later into a true pupa" (Williston '08). 



The family includes a single genus, Lonchoptera, of which only 

 three North American species are known. 



Suborder CYCLORRHAPHA* 



The Circtdar-seamed Flies 



To this suborder belong those families of flies in which the pupa is 

 always enclosed in a puparium from which the adult escapes through 



*Cycl6rrhapha : cyclos. (k^kXos), a circle; rhaphe, (pa(piq), a seam. 



