XXVIII. FAMILY LONCHOPTERID^). 



Small (2-4 mm.), slender, brownish or yellowish flies. 

 Antennae short, third joint rounded or globular, with a 

 terminal bristle. Ocelli present; front bristly. L,egs 

 long, bristly; pulvilli very small; empodia wanting. 

 Wings lancet-like, pointed, the basal cells of small size 

 and nearly equal length; fourth longitudinal vein fur- 

 cate; first longitudinal vein short, second and third not 

 furcate; the anterior cross- vein lies near the base of the 

 wing, in front of the middle of the second basal cell, and 

 is oblique in position. 



Xs^^xT^**^ 



Fig. 92. Lonchoptera, wing and head of female. 



There is but one genus in this singular family, Lon- 

 choptera, the members of which may be found, often in 

 large numbers, in the grass or upon stones along the 

 margins of shady brooks. The larvae live under leaves 

 and partially decomposed vegetable matter; they are 

 flat, with long bristles on the first, second and last seg- 

 ments; posterior spiracles broadly separated on the last 

 segment, short and tubular; head not differentiated; the 

 body composed of ten segments, the 1'ast one apparently 

 formed of two. The larva transforms into a sort of semi- 

 pupa within the last larval skin, and, later into a true 

 pupa. The venation of the male differs from that of the 

 female in the termination of the hindmost vein. 



240 



