240 G- ^- Osten Sacken: Diptera 



Of D. spreta I have but two, very indifferently preserved spe- 

 cimens. The arrangement of the cephalic and thoracic bristles is the 

 same as in D. digna, only they are weaker; those on the pleurae 

 especially are very small, and require a strong lens. On the upper 

 side of the middle tibiae I perceive but a single bristle, a little distance 

 from the base; but I am not sure whether this in not owing to the 

 imperfect preservation of the specimens. The little spines on the under- 

 side of the hind femora are wanting here; and, from the silence of 

 Mr. Jaennicke about them, I judge that they are also absent in his 

 C. fasciatus. The posterior crossvein is less oblique and not quite so 

 near the hind margin; this seems also to be the case C. fasciatus. 



Dryxo belongs apparently in the member of those Notophilina, 

 which, like, Paralimna and Corythophora, have the second an- 

 tennal joint not unguiculate, but provided with a very minute bristle; 

 nevertheless, the presence of some bristles on the upper side of the 

 middle tibiae vindicate its position within that group, (in accordance 

 with the arrangement adopted by Loew; see Monogr. N. Am. Dipt. I, 

 p. 131). With both of the above quoted genera Dryxo has the pro- 

 longation of the costal vein as far as the fourth vein in common. But 

 it is abundantly distinguished from Paralimna by the projecting face 

 and front, the great scarcity of cephalic and thoracic bristles etc. 

 Corythophora (Loew, Ofv. K. Vet. Ak. Forh. 1862; S. Africa) 

 I do not know; it may be closely related to Dryxo; it also has a very 

 oblique posterior crossvein; but the words ,,scutellum crassum" and the 

 adjective validae, apphed to the bristles on the middle tibiae, prevent 

 me from assuming the identity. 



The position of Dryxo among the Notiphilina is, no doubt, so- 

 mewhat artificial. R. Desvoidy placed it near Ochthera; and indeed 

 the bareness of the thoracic dorsum, the arrangement of the cephalic 

 bristles, the venation etc., may indicate a relationship between them. 

 Loew placed Ochthera at first among the Ephydrina (Monogr. N. A. 

 Dipt. 1. c), but removed it afterwards among the Hydrellina (Berl. 

 Ent. Z. 1874, p. 78.) 



Of the four species at present known, D. Uspoidea R. D.( Su- 

 matra) is seven lines long, and therefore certainly distinct from the 

 others. Cyphops fasciatus Jaenn. (Java) has some points in common with 

 my D. spreta, but is probably distinct, — as will be shown below. 



I happened to identify this genus TJryxo R. D., merely because 

 I found it among Mr. Walker's determinations, and I believe that this 

 time he was right, although the Paralimnae were likewise called Dryxo 

 by him. Mr. Walker, in his works, frequently refers to Rob. Desvoidy's 



