1903.] 



271 



Mr. Butler's specimen is a brachypterous c?- I liave never seen 

 the macropterous form of either sex, but have taken the characters of 

 it from Eeuter's " Revisio critica Capsinarum prascipue Scandinaviae 

 et Fenina3." 



St. Ann's, Woking : 



September 22nd, 1903. 



AGATIIOMYIA VIDUELLA, Zett. : A NEW BRITISH FLY. 

 BY J. H. WOOD, M.B. 



Of this species, new so far as our Fauna is concerned, two males 

 and one female have been obtained ; the actual dates of capture being 



S , 14.G.02, S , 13.5.03, ? , 14.6.02. They 

 were all netted of£ one particular syca- 

 more bush in a shady keeper's path in 

 Stoke Edith Wood, one of the richest 

 bits of collecting ground in this neigh- 

 bourhood. The insect is very distinct, 

 and may be known at once from either 

 of our other two species by the dilated 

 hind legs of the male (fig.) and the deep 

 black colour of the female. Not being 

 able to run it down by the works at my 

 disposal (Schiner includes it among the 

 European species, but without a descrip- 

 tion), I was obliged to have recourse to 

 Mr. Collin, who kindly identified it, and 

 as he tells me the male has never yet been 

 described, it becomes necessary to give a 

 more detailed account of the insect than 

 A. vidueua, Zett. would otherwise have been needed. It 



Ri^bt hind leg of male. . c , i j. 



is therefore unfortunate that neither of the males is perfectly mature, 

 which has led to a partial collapse of the dilated hind legs, and in one 

 of the examples has also left them of an unnatural pale colour. This 

 does not, however, materially affect the describer's work, but it has 

 placed Mr. Collin at a disadvantage, who in his drawing has been 

 obliged to represent the limb as it is, rather than as it should be. 



S The most obvious character is the excessive dilatation of the hind legs, the 

 femora being stout, the tibi^ gradually and v^idely dilated, and the basal joint of 

 the tarsi long and greatly swoUen-in fact, the legs of a CalUmym rather than of an 

 Agathom^ia. The curved bristle underneath the front femora is present, but 

 smaller than in allied species. Other important characters are the absence of the 



