ASnMEAD : CLASSIFIf'ATION OF THK CIIALCIO FLIES 331 



10. Abdoincn ovate, tlio sccoiul and tliird segniciit.s very larfie, occupyiiij; the larger part of the surface. 



Cyrtogaster Walker (type C. vulgaris Walker). 



11. Metanotum punctate, with an abbreviated median carina 12 



IMetanotum smooth, inii)unctate, but with a distinct median carina. 



Pronotum anteriorly not acute ; axilhe separated at ba.se of scutellum ; abdomen ovate or conic- 

 ovate, the second sejiincnt larfrc, occuiiying about half the whole surface. 



PolycystUS Westwood (type P. mallheirsii Westw.). 



Pronotum anteriorly acute; axilla; meet at base of scutellum ; abdomen trianf;ulate<l, nuicli as 

 in Perilampus, the second segment large Trigonogastra Ashmead. 



12. Alidomen short, ovate, wider than the thorax, but a little shorter, the second segment twice the length 



of the third, the apical margin entire, the following segments gradually shortening. 



Eurydinota Forster (type E. leptonimt Fdrster). 



13. Abdomen with the second segment occupying fully one third the whole surface, 3 to 5 subetiual in 



length, the sixth longer than the fifth, the two following very short. 



Pterosema Forster (type P. rariicolor Fo:-st.). 



14. Metanotum not closely punctate and tricarinate 15 



Metanotum not long, and smooth, the median carina and lateral folds usually present. 



Middle tibiae normal ; abdomen ovate, pointed at apex, the petiole shagreened, with a median 

 ridge, the second segment the largest, occujiying about half the whole surface, with a slight 

 incision at apex Polycystus Westwood. 



Middle tibia; abnormal, incrassate ; abdomen short ovate Spaniopus Walker 



(type S. diaaimilis Walk.). 



15. Abdomen conic-ovate, the petiole rugulose, the second segment occupying at the most one third the 



whole surface, the following segments subequal, less than half the length of the second ; pronotum 



not short Bubekia Dalla Torre (type Brachycrepw tricarinata Ashm.). 



Ifi. Petiole of abdomen long, always longer than the hind coxa> 17 



Petiole of abdomen shorter, not longer than the hind coxa" 2i) 



17. Mesothoracic furrows complete IS 



Mesothoracic furrows incomplete, indicated only anteriorly 21 



18. Head with compressed cheeks ; pronotum not large, not transverse (piadrate 19 



Head sublenticular, with rounded cheeks, the vertex antero-posteriorly narrow ; antenna; lilifbrm, 



pubescent. Syntomopus Walker. 



19. Scutellum with a cross-furrow before apex 20 



Scutellum without a cross-furrow before apex 28 



20. Abdomen with dorsal segments 2 and 3 large, the second twice the length of the third and deeply, 



broadly, semicirculai-ly emarginate at apex ; flagellum subclavate, pubescent . . . Merismus Walker. 



Abdomen ovate, the second dorsal segment large, occupying more than half the whole surface, not 



emarginate at apex Acroclisis Filrster. 



21. Metanotum usually smooth, with lateral folds and a median carina ; both mandibles 4-dentate .... 24 

 Metanotum closely punctate and often, but not always, without lateral folds or a median carina, rarely 



distinct 22 



22. Abdomen not triangular, either oval or oblong-oval 23 



Abdomen triangular ; mandibles 4-dcntate, the outer tooth acute ; pronotum anteriorly truncate, the 



upper front margin acute Trigonogastra Ashmead. 



23. Metathorax not long, but pro<luced into a subglobo.se neck at apex ; both mandibles 3-dentate .... 24 



