The Scottish Naturalist. 179 



maggot ; at each side of the tip behind this, there is a tubercle 

 on each side ; the adjoining parts are nearly on the plane of the 

 body, and the anus is indicated by a fissure ; length 4 lines. 



The fly agrees best with Syrphus chalybeatus, Meig. Europ. 

 Zweif. Ins. iii. 294, of which he describes a male. There are 

 some slight discrepancies ; but as the species is subject to 

 variety in its tints, I do not feel justified in considering it as 

 different. It belongs to the genus Cheilosia of Macquart, to 

 whose plates I must refer for a figure of the wing. It is some- 

 what narrowish, obscure olive-green, or, in the male, slightly 

 blueish, shining; face with two tubercles, the upper largest: 

 black, with several whitish patches and reflected tints, especially 

 round the margins of the eyes ; in some lights quite hoary : 

 the head surrounded with whitish pubescence, hinder part of 

 the head pale-greyish ; front black or greenish, punctulate, wide 

 in the female, but, in the male, the eyes almost meet, a tri- 

 angular space being left in front and behind ; eyes brown, 

 yellowish white pubescent ; antennae smallish, the base black, 

 with the third lenticular joint more or less deep fuscous, the 

 first and second in such instances being paler next the joints, 

 clothed with a thickish white or slaty down ; seta apparently 

 naked ; thorax greenish or blueish-black, shining, finely punc- 

 tulate, and having a fine retiform tracery on the surface, and a 

 thickish yellowish white pubescence, mixed with black hairs ; 

 the pubescence white on the sides, in the female neither so 

 long nor dense ; scutellum concolorous, a shallow arched 

 depression before the tip, pubescent ; abdomen rather narrow- 

 ish, flattish, oblong-oval in the males, broader and bluntish in 

 the females, concolorous, reticulated, rather thickly yellowish 

 pubescent, the pubescence mixed with a few black hairs ; the 

 belly, in the female, with the hinder edges of the segments, the 

 base, and some tints on the middle subtestaceous ; legs black, 

 thighs with a pale yellowish pubescence, which becomes 

 blackish on the anterior; tibiae and tarsi on the inside and 

 beneath with a shining thick short appressed yellow down ; 

 tips of the femora, base and tips of the coxae yellow ; the fore 

 and middle tibiae often with a black ring in the middle, the 

 remainder being yellow ; the anterior sometimes with the inside 

 entirely yellow ; the middle part of the hinder tibiae sometimes 

 brown ; tarsi, on the outside, brownish, duskier towards the 



