FAMILY EMPID.E THE DANCE FLIES 207 



Molandor has covered this family in Genera Inseetornm* describ- 

 ing many new North American genera and species and presenting keys. 

 Unfortunately the price of this work is prohibitive to the average 

 worker so the family will no doubt receive little attention until a more 

 readily accessible work is available. 



KEY TO GENERA 



1. Discal cell always united with the second basal, the anal cell always 



incomplete 55 



Second basal closed apically or the anal cell complete 2 



2. Mesopleura obliquely long:er than high 3 



Mesopleura distinctly higher than long 4 



3. Anterior pair of legs far from the middle pair, raptorial 52 



Anterior legs not distant from the middle pair and not raptorial ... 43 



4. Auxiliary vein distinct and separated from the first vein 5 



Au.xiliary vein weak and lying close to the first vein 13 



5. Anal cell very much longer anteriorly 22 



Anal cell longest posteriorly, transverse apically or but little longer in 



front than at the middle 6 



6. Costa ending at the third or fourth vein; two veins emitted by the 



discal cell 8 



Costa continuing around the wing; three veins emitted by the discal cell 7 



7. Third vein forked (14) Brachystoma Meigen 



Third vein simple (28) Anomalempis Melander 



8. Fourth vein not forked 9 



Fourth vein forked (30) Meghyperus Lcew 



9. Pedicel of the second and third veins arising beyond the middle of the 



second basal cell 10 



Pedicel arising near the basal fourth of the second basal cell (25). 



Syneches Walker 



10. Vein between the first and second basal cells distinct, the first basal 



cell not much wider than the second 11 



Vein between the first and second basal cells very weak, the first basal 

 very much wider than the second (31) Syndyas Loew 



11. Third and fourth veins convergent apically 12 



Third and fourth veins parallel or diverging (1, 21) Hybos Meigen 



12. Disc of mesonotum without pile; palpi elongate (35). 



Lactistomyia Melander 

 Disc of mesonotum more or less densely pilose; palpi short. 



Eubybos Coquillett 



13. Discal cell present 15 



Discal cell absent 14 



* Fascicle 1S5. 1921 



