Piatype zid ae. 3 



legs are dilated in both sexes, sometimes more in male than in female, 

 but in Platypeza most in the female; the tarsi may otherwise be 

 variously constructed, sometimes, as in Callimyia and Agathomyia, 

 the metatarsus is the longest joint, but in most species of Platypeza 

 the metatarsus is short to very short and then generally shortest in 

 the female, and the third and fourth joint are in this sex of a special 

 shape. In some species of Agathomyia the dilatation is weak or almost 

 not present. In Callimyia and some species of Platypeza also the 

 middle tarsi in female are a little dilated. The legs are upon the 

 whole not much hairy, generally only the femora have more or less 

 long hairs, and as a rule they are short-haired in the female. 

 Of bristles various characteristic ones are often present in male; 

 middle tibiæ have one or two apical spurs. Claws and pulvilli small, 

 generally a little larger in male than in female. Empodium quite 

 small or nearly wanting. Wings with the membrane clear even if 

 yellow, and of a somewhat glassy appearance, except in Opetia and 

 Platycnema. Costa reaching to the discai vein, in Opetia it seems 

 to go all round ; subcostal vein somewhat long, in Callimyia spinulose ; 

 cubital vein unforked; medial cross-vein somewhat near the base, 

 but first basal cell longer than second, except in Platycnema^ discai 

 vein unforked in Platycnema^ Callimyia and Agathomyia^ in Opetia 

 with a long fork, and in Platypeza forked at apex, the upper branch 

 ending in the margin, the lower as a rule more or less abbreviated. 

 In Opetia and Platycnema no posterior cross-vein and thus no closed 

 discai cell, in the other genera a posterior cross-vein present, placed 

 near margin, and thus a long discai cell present. Anal cell shorter 

 or longer, but always longer than second basal cell, though in Opetia 

 only slightly. Anal vein reaching the margin except in Opetia] axillary 

 vein more or less indistinct. A stigma present in Platycnema. Axillary 

 lobe well developed ; alula quite narrow or somewhat well developed. 

 Thoracic squamula small, alar squamula larger, both with long mar- 

 ginal hairs; they have the angulus somewhat protruding, with the 

 hairs fan-like. 



The wing-venation is somewhat similar to that in Syrphidae, 

 but the upper branch of the discai fork ends always in the margin 

 and thus first posterior cell open, the basal cells are much shorter, 

 and also the anal cell shorter; Opetia and Platycnema are still more 

 different. 



The developmental stages of Callimyia and Platypeza are known. 

 The larvæ are more or less flattened, rarely cylindrical; they are 



1* 



