on [January, 



epecimens) than the sides of the frontalia ; the fronto-orbital bristles only extend a 

 short way down the face, three or four being placed below the roots of the antennae 

 in an irregular row or patch (especially in the male) ; the third joint of the antennae 

 is about four times the length of the second ; the faeialia are almost nude ; the 

 thorax is black, very hoary on the front and sides, and marked by four slender 

 stripes ; the abdomen is rather setose, having bristles both on the disc and margins 

 of the segments, it has the sides lioary, with the centre of the dorsum black, as well 

 as the hind margins of the segments ; the wings have the outer and apical cross veins 

 both nearly straight, the former being placed near to the angle of the latter. I re- 

 ceived three specimens of this rare fly from Mr. Fitch some years ago, all of which 

 were bred from Acronycta tridens. 



E. JucujfDA, Mgn. 



This rather small species (6 mm. in length) has the scutellum wholly black or 

 rather grey. The palpi are yellow ; the antennae long, thick and straight, the second 

 joint being very short, and the third five or six times as long ; the arista is thickened 

 for nearly two-thirds of its length, the thickened portion ceasing rather abruptly ; 

 the thorax and abdomen are grey, being coated with hoary pubescence, the former 

 has four stripes, the central pair narrow and the outer ones wide and interrupted ; 

 the abdomen is tessellated with black patches, which assume the form of black bands 

 when viewed from behind ; the segments are armed with rather small setae on both 

 the discs and posterior edges ; the venter is grey with white margins to the seg- 

 ments ;* the wings have the apical cross veins concave, and terminating close to the 

 apex of the wing. Not common. I found one specimen at Bingley, near Bradford, 

 in 1874, and another at Silverdale in North Lancashire in 1881 ; it is also in Miss 

 Decie's Collection. 



E. parens, Rnd., has been recorded as a British species, and in 1880 I received 

 two flies from Mr. Bignell (bred from Folia Jiavicincta) which I thus named ; upon 

 further research, however, I believe that they were only varieties of E. vulgaris, and 

 I now doubt whether E. parens is a distinct species. E. prominens, Mgn., is another 

 doubtful species, Meigen omitting the colour of the palpi. I formerly labelled 

 several specimens with this name, one of which is in Mr. Dale's collection. I now 

 think that tliey are also varieties of E. vulgaris. 



(To be continued). 3 5 



DOUBLE-BROODEDNESS: WHETHER INFLUENCED BY THE STATE 

 OF THE FOOD-PLANT? 



BY F. MERRIFIELD, F.E.S. 



The statements in your December number as to Stauropusfagi proving partially 

 double-brooded during the past season, lead me to invite a consideration of the 

 question with which I have headed these remarks. For experimental purposes I 

 have during each of the last four years bred, or had bred for me, not less than ten 



* Macquart says by mistake " incisions noires ; Meigen, however, states that the lines are 

 white, and I find them to be so. 



