8 Platypezidae. 



2. Platycnema Zett. 



Small black species. Head a little broader than thorax, flat 

 behind. Eyes large in male, touching for a very long space, so that 

 only small vertical and frontal triangles are left; in female the eyes 

 widely separated. On vertex there is a pair of ocellar bristles, and 

 in female a coiiple of frontal bristles on each side. Along the hinder 

 eye-margin a row of postocular bristles, longest above. In the male 

 the eye-facets in a larger upper part of the eye are much enlarged. 

 Antennæ inserted near to each other, considerably below the middle 

 of the head; the basal joints are small, the third triangularly roundish, 



Fig. 2. Wing of P. pulicaria ,^ . 



pointed, with an apical arista more than double as long as the an- 

 tenna; the arista is distinctly pubescent. Face very small; jowls 

 not descending. Proboscis small and retracted. Thorax rectangular, 

 much higher than long and highly arched above. There are somewhat 

 long, biserial acrostichals, and on each side a similar single row of 

 dorsocentrals, the two hindmost of which are very long; besides 

 some smaller hairs outside the rows; further there are a humeral 

 bristle, two posthumeral (or the one præsutural), three notopleural, 

 two supraalar and a postalar bristle. For the rest thorax is bare. 

 Scutellum has four long marginal bristles. Pleura bare, except for 

 a prothoracic bristle. Abdomen elongated, somewhat narrow and 

 tapering; it consists in the male apparently of seven segments; then 

 follows the hypopygium, which is directed backwards, not bent 

 ventrally; it consists of two broad side-lamellæ, forminglike a forceps, 

 and between them at the apex tw^o very thin styliform upper lamellæ, 

 stretching upwards ; it is thus like the hypopygium in many Empidids. 

 Abdomen has bristles at the hind margins to the segments. Legs 

 with hind tibiæ dilated and hind metatarsus slightly; the legs are 

 somewhat fringed on femora and tibiæ, and the femora have a longer 



