52 AN ACCOUNT OF BRITISH FIIES. 



T ^ -AT I Mi7nosdara, Rd. 



lestre/ma, Macq. = J 



I. Yposahm, Rd. 



Ocelli wanting. Wings pubescent. Antennae moniliform in ^ ,. 

 sub-moniliform in ?, i6 joints. First longitudinal being short, third 

 forked (Fig. 7a). 



Colpodia, Wtz. One species is reputed as British. The second 

 longitudinal vein forms a curve before the cross-vein, and joins the 

 margin beyond the tip of the wing (Fig. Sa). 



Cecidogjia, Lw., antennae ii-jointed;* Micro/nyia, Rd., is another 

 genus found in Britain, and given in Bergenstamm and Low's work. 



Zygofieura, which shows certain affinities to the Cecidoviyidce men- 

 tioned before, and also to Sci'ara, one of the Mycetophilidu^ is now 

 included in the latter family ; but is no doubt a transitional form 

 between the two. Anarete is now placed in the Bilnonidce. 



The following are the genera and sub-genera found in England, 

 the names being those used by Verrall and in Bergenstamm and 

 Low's classificationf : Lasiopiera, Mg. ; Cecidomyia, Mg. ; Asphon- 

 dylla, Lw. ; Diplosis, Lw. ; Horniomyia, Lw. ; Dirrhiza, Lw. ; Epi- 

 dosis, Lw. ; IVinnetzia, Rd. ; Campylomyza, Mg. ; iMicroinyia, Rd. ; 

 Catocha, Hal. ; Lesfremia, lsicc[.X Most of these are considered 

 sub-genera of Cecidomyia by Loew ; by others as true genera. By 

 tar the most important is Cecidomyia proper, which contains as many 

 as fifty species indigenous to Britain,^ and amongst these by far the 

 most interesting and important is the Hessian-fly {C. destructor), 

 which we now proceed to describe, with other species of this sub- 

 genus. 



o r^ ^ -7 ■ T \Dasyneura, Rd. 



Sub-Genus. — Cecidomxia, Lw. = -. , , , , 



yRIiabdophaga, \\ estw. 



Cecidomyia destructor. Say (the Hessian-Fly) . 

 The egg of the Hessian-fly, which is small and cylindrical, is 

 described by some as being rounded at each end, by others as being 

 pointed at each end,|| pale-orange colour at first, with reddish dots,, 

 becoming darker later and transparent the third day ; about "02 mm. 

 long by '008 broad. The larvae emerge on the fourth day. Accord- 

 ing to Mr. Enockjii a female will lay from 100 to 150 eggs; others 

 say as many as 2 So. They are laid on many separate plants of 



* This is now merged into the sub genus Lcstremia. Dio/nyza, C/inoiyni/ia, 

 Hderopeza and Tritozyga are other foreign genera. 



t Synopsis Cecidomyidarium, 1876, J. E. von Bergenstamm and Paul Low. 



J The following is a reputed British genus : Colpodia. 



§ Ninety or more, if we include reputed and doubtful records. 



li "Hessian-Fly Report of Department of Agriculture, U.S.A.," p. 208,^ 

 1880-82. 



H Trans. Ent. Soc. of London, June, 1891. 



