134 Orthorrliapha brachycera. 



present; cubital vein forked; tlie discai cell foniied exclusively of Ihe 

 discai vein, a postical cross-vein present ; two cubital and Ove posterior 

 cells; the basal cells of equal length, the anal cell produced to or near 

 to the margin, open or closed. Alula distinct, rounded; squamulæ 

 alares well developed, but not covering the balteres, roundish, witli 

 one ore more fine fringes at the edge or almost bare. squamulæ 

 thoracales not developed, but the frenum distinct, especially towards 

 the angulus. In rest the wings are borne half open. 



The larvæ are elongated, the body consists of twelve segments; 

 the abdominal segments have often transverse swellings on the ventral 

 surface; the last segment generally with some teeth or spine-like 

 warts on the apex. They are amphipneustic with prothoracic and 

 terminal spiracles, the latter sometimes lying between a pair of trans- 

 verse lips; in one case {Atherix) the larva is recorded to have tracheal 

 gills. The pupa is free, it has generally some (6) spines on the apical 

 segment. The larvæ are carnivorous and feed on other larvæ, earth- 

 worms and the like, or they penetrate into and devour beetles; they 

 live in the earlh or beneath the carpet of leaves in woods, or (Atlierix) 

 in water; the larva of Ehugio (southern species) forms funnels in the 

 ground as the Myrmeleon-\a.v\d,. The pupæ are found in the earlh. 



The Leptids are small to rather large flies; they are rapacious 

 and feed on other Insects; they generally occur in woods in shady 

 piaces where they are sitting on stems of trees. watching for prey, 

 some species occur also in low herbage especially in damp piaces in 

 thickets. It is recorded that the females of some species bite and 

 suck blood like Tabanids. Thus Osten Sacken iias recorded it with 

 regard to an American species of Sijmplioromijia, and it is said uf a 

 South American species {Trichopalpus obscurus) and finally of Leptis 

 strigosa and of both sexes of L. scolopacea. As the females of Si/m- 

 phoromijia have mandibles, it is not improbable that these may suck 

 blood which then perhaps also holds good of Atherix, but I think it 

 not very probable with regard to Leptis, and I never observed it in 

 L. scolopacea which is a common species in Denmark. 



Of the family about 90 species are known from the palæarctic 

 region, and a similar number from North America; none are known 

 to be conmion lo both regions. 



I am aquainted with no case of parasitic Hymenoptera on Leptids. 



Leptids earlier recorded from Denmark — The first Leptid 

 recorded from Denmark is Musca triuguria, found in the appendix 

 to O. F. Muller: Flora Fridrichsdal., 1767; this common species 

 was probably correctly determined. Then follows in 1794 Fabri- 

 cius: Entom. Syst. IV. with Rhagio vaneJhts = Leptis triiigaria. R. 



