ORTALIDJE SYSTEMATIC DISTRIBUTION. 43 



disciform, but representing a swelling of the gula, and hence, re- 

 minding of a similar structure in Loxoneura, in which it fills the 

 greater part of the oral opening. Proboscis but little swollen ; 

 palpi of a moderate breadth. Thorax very stout. Abdomen 

 comparatively very short and narrow, consisting of four seg- 

 ments. Feet long ; wings very large ; the end of the auxiliary 

 vein almost obliterate ; the second longitudinal vein very strongly 

 bisinuate ; the third and fourth strongly convergent towards 

 their end ; the posterior crossvein very oblique ; all the basal 

 cells very long ; the anal cell has an acute posterior angle. 



Among the species which Wiedemann places in the genus 

 Ortalis, there are three closely allied ones, which do neither be- 

 long in the genus Ortalis, nor in the group Ortalina. They 

 have to form a separate genus in the group Platystomina, which 

 I will call ENQISTONEURA. They are : Ortalis moerens Fab., 

 parallela Wied., and lugens Fab. ; Trypeta albovaria Walk., 

 may be added as a fourth species, unless it is synonymous with 

 0. moerens Fab., which may possibly be the case. The follow- 

 ing characters distinguish the genus Engistoneura. They are 

 large flies of yellowish coloring, with a very much developed 

 thorax, especially broad between the roots of the wings; its con- 

 vexity, however, is very small ; the abdomen is comparatively 

 small, of a metallic violet color. The structure of the head some- 

 what reminds of Dacus. The antennae reach the middle or a little 

 below the middle of the face ; the long arista is distinctly 

 feathery. The foveae, which reach a little below the middle 

 of the face, are very sharply defined. Clypeus distinct ; pro- 

 boscis of moderate stoutness, with a but little developed men- 

 turn; palpi rather broad. Scutellum large, but little convex, 

 overhanging the metathorax more than in most of the other 

 genera of the Platystomina; it has six bristles. Abdomen 

 rather cylindrical. Feet of moderate length and not very strong ; 

 the front femora on the under side, in the vicinity of the tip, with a 

 few bristle-like spines. Wings large, rather narrow towards the 

 basis, broad towards the apex ; auxiliary veins of moderate 

 length, turning abruptly towards the costal margin, and becom- 

 ing almost obliterate ; the first longitudinal vein approaches 

 closely to the margin beyond the end of the auxiliary vein, and 

 runs alongside of it as far almost as the end of the second longi- 

 tudinal vein ; the third longitudinal vein is strongly bent back- 



