312 



THE STUDY OF IXSECTS 



The larva? live in various situations, some in the ground or in decay- 

 ing wood, and some species are aquatic; they are believed to be either 

 predacious or scavengers. The pupae are free. 



This family is a large one. 



Family Lonchopterid^e 

 The Spear-winged Flies 



These are minute flies, which measure from -^ to -J of an inch 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. 552). This suggested 

 the family name. 



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

 distinguish these flies from all others. 



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

 places. They frequent the shores of shady brooks, where the atmosphere 

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



" The larvae live under leaves and decomposed vegetable matter." 



The family includes a single genus, Lonchbptera. 



Fig. 552. — Wing of Lonchoptera, female. 



Suborder CYCLORRHAPHA* 



The Circular-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 a round opening made by pushing off the head-end of it. 

 (Fig. 553); the cap thus pushed off is often split lengthwise, as 

 shown in the figure. The adult flies possess a frontal lunule and 

 except in the first three families a frontal suture, through which the 

 ptilinum is pushed out, when the adult is about to emerge from the 

 puparium. The antennae are usually three-jointed and nearly all have a 

 terminal or dorsal arista, — rarely with a terminal style. 



* CyclSrrhapha: cyclos, (kvkXos), a circle; rhaphe, (pa<pij), a seam. 



