GEIlA>fOMYIA. 387 



Geuns GERANOMYIA, Hal. 



Gemnomyid, Haliilay, Ent. Moiitli. Mag. i, p, 154 (1833). 

 Limnobiorhynchus, Westwood, Ann. Soc. Ent. France (1) iv p. 683 



Aporosa, Macquart, in Webb and Berth. Hist. Nat. d'lles Canaries 



Entom. Dipt. p. 100(1838). 

 Plettusa, Phil., Verb, zool.-bot. Ge.s. Wien, xv, p. o97 (I860). 



Genotype, Geranoimjia imicohr, Hal.; by original designation. 

 Head : proboscis conspicuously prolonged, longer than head and 

 thorax together. The mouth parts " consist of a very long sub- 

 cylindrical epistoma, a still longer lingua, which is slender and 

 pointed, and a labium divided in two branches at the tip, ter- 

 minated by slender flattened lobes ; these branches are divergent 

 and sometimes curled up in dried specimens." (Osien SacJcen.) 

 The short palpi which, according to Curtis, are biarticulate, are 

 inserted between about the middle of the proboscis and the 

 anterior angles of the rostrum.* Eyes rounded or oval, approxi- 

 mate or divided by a tolerably wide frons. Auteunre 14-jointed, 

 submoniliform, the joints not pedicelled. Thorax and abdomea 

 normal. Genitalia of the male like that of Dicranomyia ; two 

 fleshy movable lobes with horny appendages, and a hornv ventral 

 plate below them. Legs slender; tibia? without spurs, "empodia 

 indistinct or absent, ungues with teeth on underside. Wim/s 

 elongate. One submarginal cell, four posterior cells, and the 

 discal cell normally closed. Venation practically identical with 

 that of Dicranomyia, except that the auxiliary vein is generally 

 prolonged some little distance beyond the origin of the 2nd vein, 

 much as in Limnobia ;■ the range of variation in the characters 

 of the difl:erent veins and cells appears, at least in the Oriental 

 species before me, to be less than in Dicranomyia. The auxiliary 

 vein always ends distinctly beyond the origin of the 2nd vein, 

 often as far beyond as half-way froiri that point to the tip of 

 the 1st longitudinal vein ; the subcostal cross-vein placed near its 

 tip, often very difticult to perceive ; marginal cross-vein oblique, 

 generally at or beyond the middle of the marginal cell, near or at 

 the tip of 1st longitudinal vein ; discal cell pentagonal, squarish 

 or seldoni more than twice as long as broad ; posterior cross- 

 vein varying from a little before to a little beyond the base of the 

 discal cell. 



llanrje. The genus has been recorded from every region in the 

 globe except Africa, but a species is known from the island of 

 Bourbon, off Mauritius. 



Life-history. Apparently unknown but probably similar to that 

 of Dicranomyia and Limnobia. 



Geranomyia is represented in a fossil state by two specimens 



* For a splendid plate, giving anatomical particulars of this gemis, see 

 Curtis, Brit. Entom. p. .573 Walker, in liis Insecta Britannica, Dipt! iii, 

 pi. xxvii, fig. 6, reproduces Ciirtis's figures of the dissected ]}roboscis. 



