. Fig. 42. Wing of ?. Length. The species varies much in size, the length varying in all from 2 to 5,5 mm, the female is always the larger; for the male the length is 2—3,5 mm for the female from fully 3—5,5 mm. Ch. thoracica is rather common in Denmark, Vesterfselled, Erme- lund, Dyrehaven, Holte, Bogo south of Sealand, on Langeland at Lohals, on Lolland at Lysemose and in Jutland at Ry, Grejsdal at Vejle and Hejls south of Kolding; the dates are ^^U—^^U, but bred specimens emerged at the end of April. Pupae were taken on Vester- faelled on Vi and in Dyrehaven on ^^4, the latter
. Fig. 42. Wing of ?. Length. The species varies much in size, the length varying in all from 2 to 5,5 mm, the female is always the larger; for the male the length is 2—3,5 mm for the female from fully 3—5,5 mm. Ch. thoracica is rather common in Denmark, Vesterfselled, Erme- lund, Dyrehaven, Holte, Bogo south of Sealand, on Langeland at Lohals, on Lolland at Lysemose and in Jutland at Ry, Grejsdal at Vejle and Hejls south of Kolding; the dates are ^^U—^^U, but bred specimens emerged at the end of April. Pupae were taken on Vester- faelled on Vi and in Dyrehaven on ^^4, the latter developing on ^^4; in both localities they were taken in moles' nests (Rosenberg). The species occurs otherwise in low herbage, and I have also taken a specimen on an umbellifer; but generally the species may be seen in some numbers on tree-stems, as also often recorded; in this way I have taken it at Lohals and Hejls in the middle of July, and it seems that the copulation takes place here, for I have taken it in copula on the stems on ^^Z?; when occuring on the stems the females had very often the above mentioned abdominal sacks more or less extended so that it seems rather probable that these sacks have something to do with the copulation. Geographical distribution: — Europe down into France, towards the north to Lapland; also in North America.
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Keywords: ., bookauthorlu, bookcentury1900, bookdecade1900, booksubjectdiptera
