88 Orthorrhapha brachycera. 



in length from not half as long as the head is high to nearly as long 

 as the body; in rest it is retracted (when short) or protruding (when 

 long). Labiuni has the basal part short when the proboscis is short, 

 but when this is long the basal part is much longer than the labella; 

 these latter are in the short proboscis more or less broad and disci- 

 forra when spread out, in the long proboscis they are narrow, not 

 broader than the basal part, but cleft to their base. Labrum gene- 

 rally as long as the basal part of labium or slightly longer; hypo- 

 pharynx and maxillæ of a similar length; hypopharynx forming a 

 longpointed, chitinous blade, the maxillæ of a similar form, or, when 

 the proboscis is long, very thin, nearly thread-like ; the maxillary palpi 

 shorter or longer, one-jointed. Thorax generally nearly quadrate, 

 slightly or somewhat more arched above. Of macrochætæ some 

 bristles are generally found, which on account of their being placed 

 on the præalar cailus may I think be termed notopleural; moreover 

 postalar and more or less weak scutellar marginal bristles are gene- 

 rally present; sometimes the bristles are hidden in the clothing fur. 

 Metapleura generally with a vertical tuft of hairs, sometimes bare 

 {Argyramoeba, Phtkiria). Abdomen somewhat flat, or more arched, 

 with more or less parallel sides, or short and ovate; it consists of 

 seven not transformed segments. Genitalia formed of the eighth and 

 ninth segments. Legs slender, generally with bristles which are how- 

 ever not strong; the front legs sometimes smooth. Apical spurs pre- 

 sent on all tibiæ or only on the posterior; they are generally small. 

 Claws not strong ; pulvilli generally present but of different size, some- 

 times very small and sometimes quite absent. Empodium lobe-shaped, 

 small or rudimentary, in rare cases it is larger and then similar to 

 the pulvilli {Cyrtosia). Wings with the costal vein extending all round 

 the margin; the venation sometimes shows some curious appearances, 

 the cubital vein either issuing in a normal way from the radial vein, 

 or the radial and cubital veins united for a distance at their basal 

 part and then the radial vein suddenly rising from the cubital vein 

 with an angularly bent base; thus the radial vein apparently rising 

 from the cubital vein; the cubital vein branched, two cubital cells 

 (in non-Danish genera there may be up to five cubital cells on account 

 of the presence of surnumerary cross-veins or branches, or on the 

 contrary the cubital vein is unbranched, and there is then only one 

 cubital cell) ; the discai cell formed by the discai vein but below ifor 

 a shorter or longer distance closed by the upper branch of the postical 

 vein, there is thus no postical cross-vein ; (in Cyrtosia there is no 

 closed discai cell). Four posterior cells (on account of the third and 

 fourth being confluent to one: sometimes there is a veinlet at the 



