136 Orlhoirhapha brachycera. 



reniforni with an arista goiiig ont froni tlie iipper part. Eyes bare, 



the facets in the male slighlly une(|ual. With regard to the iiioutli 



parts I have not been able to exaniine these in any other way tlian 



with a iense and in situ, I therefore chiefly am 



obliged to reter to tlie description given by 



Becher, (Denkschr. d. Kais. Aicad. d. Wissensch. 



Wien, Math. nat. Ciasse, XLV, 1882, 143, Taf. II, 



Fig. 20). The ciypeus is not separated ; the 



proboscis is rather short (longer in marginata 



than in ibis), the labella are long oval, not 



broad, longer than the basal part of the labium. 



There is a difference in the mouth between 



the sexes. The females have, as in the Taba- 



nids, both mandibles and maxillæ, these are 



Fig. 41. Antenna ot formed about as in the Tabanids; the iabrum 



Atherix ibis. j^ ^^ ^j^^^ ]Q^^^^l^ q( the proboscis, poinled, the 



hypopharynx is shorter. In the males the mandibles are wanting, and 

 Becher says: „Diesen (the medes oi Atherix and St/inphoronii/ia) sche'mt 

 aber noch ausserdem auch die Stechborste (hypopharynx) zu fehlen", 

 this statement is, 1 thinck, not correct, (see about the question under 

 Symphoromyia). There are two-jointed maxillary palpi, the second 

 joint is long, somewhat curved. Thorax is nearly quadratic. Abdomen 

 is somewhat elongated, consisting of seven segments. The male 

 genitalia are somewhat knob-like with a pair of styies. The front 

 tibiæ without apical spurs, the posterior tibiæ with two apical spurs; 

 the front tarsi long with some curious, delicate, longisii hairs on the 

 under side. Wings with the anal cell closed. 



The larva is described and iigured by Dufour (Ann. de la Soc. 

 Ent.deFr. Sér. 4, II, 18G2, 131. PI. II, tig. 2) and Brauer (Denkschr. d. 

 Kais. Akad. d. Wissensch. Wien, Math Nat. Ciasse, XLVII, 1883, Tab. III, 

 Fig. 48 — 51). It is elongated, the body consists of twelve segments; 

 on the ventral surface of each alidominal segment there is a pair of 

 prolegs, which are spined at the ends. The head is small, it has a 

 median, somewhat hooked labrum, mandibles which are serrated on 

 the outer margin, and maxillæ with two-jointed palpi. The last 

 segment terminales in a pair of longish, pointed, densely haired pro- 

 longations. On the sides of the segments there are slender, thread- 

 like appendages. The larva is recorded to have no spiracles but the 

 thread-like appendages are declared to be tracheal gills. — The pupa 

 has a girdle of eight bristles above on the abdominal segments. 



The females deposite tiieir eggs on dead branches at water, and 

 they rest there and die; many females deposite their eggs on the 



