Leptididae. 133 



Leptididae. 



Head generally short, sometimes very short, more or less semi- 

 globiilar, sometimes less so on accoimt of tlie upper front part, or 

 the face being tlattened, as broad as or narrower than the thorax. 

 Yowls very slightly, or not at all produced below the eyes. Antennæ 

 placed near to each other in the middle of the head or generally 

 lower down; they are three-jointed, the two basal joints are generally 

 short, the third may be of different form, somewhat bulb-like, ending 

 in a long arista, or oval and compressed with a thin style, or finally 

 produced downwards, reniform, with an arista going out from the 

 upper part of the front edge. I term the antennæ three-jointed, as 

 I could in no case detect any separation between the arista or style 

 and the basal part of the third joint, it seems that the third joint in 

 all cases forms an undivided totality. Eyes bare, touching in the 

 males, w^idely separated in the females. In the males the facets are 

 either of equal, or almost equal size, or the upper facets are larger 

 than the lower, and the dividing line sharp. Three ocelli present. 

 The parts surrounding the mouth aperture are chitinised, and there 

 is thus no oral cone; the epistoma is very distinctly separated from 

 the cheeks by a deep impression on each side, the impressed lines 

 thus formed unite above, below the antennæ; the epistoma itself is 

 much arched ; the clypeus is not separated. The proboscis is rather 

 short (the genus Lanipwmyia, including southern species, has a long, 

 slender proboscis); the labella are moderately broad, longer than the basal 

 part of the labium, forming an oval plate when spread out. Labrum, 

 hypopharynx and maxiilæ are much similar to the same parts in the 

 Tabanidce; they are about of the length of the proboscis, the hypo- 

 pharynx sometimes shorter; the maxiilæ are semitubular; there are 

 two-jointed maxillary palpi, the basal joint being sometimes small 

 and indistinct. in the genera Atherix and SympJioromyia mandibles 

 are also present in the females; these genera thus being very similar 

 to the Tabaiiidæ. Thorax rectangular or quadratic, generally some- 

 what arched above; metapleura with long hairs. Abdomen more or 

 less long and slender, as a rule nearly cylindrical, consisting of seven 

 segments, truncate at the apex in the males, tapering in the females. 

 Legs long, without bristles, coxæ long, front tibiæ without apical spurs 

 (Rhagio and Lampromyin with one), the middle tibiæ with two, and 

 the hind tibiæ with one or two apical spurs. The front tarsi some- 

 times with sonie long, fine hairs. Claws simple; two pulvilli and a 

 pulvilliform empodium. Wings rather ])road; costa extended all round 

 the margin, this and the subcostal vein finely spinulous; radial vein 



