314 Orthorrhapha brachycera. 



abdomen; its shape recalls that in Dolichopus; there are generally 

 long ventral lobes, variously shaped at the apex, often a little dilated, 

 incised or cleft; also small, hook-shaped middle lobes may be present, 

 but not seen when the hypopygium is in situ; the outer lamellæ are 

 shorter or longer, generally broadest at the base, more or less 

 triangular, and hairy; they are somewhat united in the middle line. 

 In the female there are five normal abdominal segments, three hidden, 

 and a small ovipositor, terminating with tvvo small lamellæ and above 

 them two small spines. There are distinct dot-like impressions on 

 the second, third and fourth segments; they are elongated, almost 

 linear. Abdomen has hindmarginal bristles only on the first segment, 

 on the others they are very indistinct or wanting. Legs somewhat 

 long and slender; they are simple, only the hind metatarsus may in 

 the males be excised at the base, and here with a small tooth; the 

 hind metatarsus is short, from a third part of to about half as long 

 as the second joint. The legs are short-haired ; the anterior coxæ 

 have a little longer, bristly hairs, the middle coxæ a bristle anteriorly 

 near the outer margin, and the hind coxæ a bristle on the outside. 

 The femora have sometimes a little longer and stronger hairs belovv, 

 the front femora on the posterior and the posterior femora on the 

 anterior side, but generally they are small and fine; there are no 

 preapical bristles. The front tibiæ have no bristles, middle tibiæ like- 

 wise, or generally with one or a pair of bristles above near the base; 

 the hind tibiæ may also have a small bristle near the base; in a few 

 cases the middle tibiæ may in the male have a bristle above in the 

 middle; in the males the hind tibiæ have generally a more or less 

 distinct bristle above near the apex, and here are also generally some 

 longer hairs; the tibiæ have apical bristles, especially the posterior 

 tibiæ a stronger bristle below ; on the front tibiæ the apical bristles 

 are small; hind metatarsus without bristles above. There are two 

 claws, two small pulvilli, and a very small, but broad and pulvilli- 

 form empodium. Wings of usual shape; the mediastinal vein termin- 

 ating in the subcostal vein, the cubital vein curved a little down- 

 wards, the last part of the discai vein without bend, straight or 

 slightly curved, more or less, sometimes strongly converging towards 

 the cubital vein; the posterior cross-vein in or generally behind the 

 middle; anal vein very weak, and also the posterior branch of the 

 postical vein weak and somewhat obliterated. The discai vein with- 

 out convexity. Squamulæ with a large, almost circular angulary lobe, 

 with a long fringe, the inner part of the squamulæ with longish hairs. 

 The developmental stages of some species are known. The pupa 

 of M. tristis is described and figured by Damianitsch (Verh. zool. bot. 



