180 NOTES ON DIPTERA. 



B.fusca, Meigen. Found in hedges, woods, &c. during 

 the spring, autumn, and winter, in various parts of England. 



Orplmephila devia, Haliday. September, North Wales ; 

 frequents moist shady spots. 



Lestremia, Macquart. This genus has more affinity to 

 Molobrus than to Cecidomyia. The antennae resemble those 

 of Zygoneuva, which is still nearer allied to Molobrus. 



Chrysomyia, Macquart. Answering to Meigen's second 

 division of Sargus, and comprising S.formosus, S. polkas, &c. 



Atherix melcena, Hoffmansegg. May, in woods near 

 London. The male probably belongs to the genus Spania, 

 Meigen. The disposition of the nervures of the wings varies 

 very much. 



Atherix immaculata, Fabricius. Found near London in 

 June. 



Tachypeza arenaria, Haliday. Inhabits sea- weed and rocks 

 on the coasts of South Devonshire, Cornwall, and the Isle of 

 Wight, during the summer and autumn. Var. ? (3. alata. 

 Alee amplce, subfuscce ad costam obscuriores. September, 

 South Devonshire and Cornwall. 



T. graminum, Fallen. September, in the Isle of Wight, 

 near Alum-bay. 



T. praelusio. Griseo-fusca, oculi obscuriores, pedes palli- 

 diores, alee august ee brevissimce sublimpidce. (Long. lin. |.) 

 Dull, pale, half the size of T. graminum ; body longer and 

 more slender, antennae very short, abdomen thrice the length 

 of the thorax, looks like a little Molobrus, runs fast, but has 

 not the activity of the preceding species. September, on plants 

 in a thick wood, near the Devil's-bridge, North Wales. 



T. ? hirta. Nigra, obscura, puree hirta, T. arenaria triplo 

 major, oculi et halteres obscure rufi, pulvilli Jlavi ; alee 

 siibfuscce amplce, nervi nigri. (Corp. long. lin. 1 \ ; alar. lin. 

 2%.) June, on sea-weed in the Isle of Wight. 



Drapetis, Megerle ; 1 aterrima, Haliday ; L Zfuscipes, Mac- 

 quart ; S nigra, Meigen ; 4 exilis, Megerle ; 5 Jlavipes, 

 Macquart. All these inhabit Britain, but probably are not 

 all distinct species, for their size and the colour of their legs 

 and wings vary very much; they run with extraordinary swift- 

 ness. D. nigra and D. exilis may be found near London 

 from May to October, among grass, and beneath planks placed 

 on decayed vegetable matter, &c. When in these situations 



