192 



[January, 



cannot satisfactorily distinguish this from the preceding ; all authors 

 seem to say it may be a variety of it, but are not sufficiently satis- 

 fied in their own minds to unite them. The distinctions most in- 

 sisted upon are the smaller size, more pellucid wings, and blacker 

 femora ; but they vary much in the femora, and I have specimens 

 fully as large as ribesii with wholly pellucid wings, and others 

 smaller than the general run of vitripennis with dark wings. I 

 hope, however, next summer to come to some conclusion concerning 

 the variations of this and the preceding species. Zetterstedt says 

 himself (Dipt. Skan., ii, 708) that the confinis described by him in 

 the Ins. Lapp., 602, 15, is only a variety of this, rather larger and 

 with darker antennae. It is more common than ribesii in gardens, 

 but perhaps less so in woods and open country. 



7. Nitidicollis, Meigen, Sys. Bes., iii, 308, 51 (1822). This species may 



be known from the four preceding by its brightly shining thorax. 

 The epistoma has also the cheeks more or less dark. The scutellum 

 being clothed with dark hairs separates it from ochrostoma, mela- 

 nostoma, and latifasciatus. For its distinction from nigritarsis and 

 nitens, see the notes upon those species (Nos. 11 and 12). It 

 occurs sparingly probably over all Europe, never seeming to be 

 abundant. It has occurred not rarely at Darenth "Wood, and oc- 

 casionally in Sussex, and even here (Denmark Hill) almost in 

 London. 



8. Ochrostoma, Zetterstedt, Dipt. Skan., viii, 3133, 12, 13 (1849). This 



may be distinguished from all the preceding by its yellow-haired 

 scutellum. It has also the whole epistoma yellow, which distin- 

 guishes it from its nearest ally nitidicolUs, and from all the fol- 

 lowing species. It is found very rarely in Northern and Alpine 

 districts. 



9. Melanostoma, Zetterstedt, Dipt. Skan., ii, 711, 13 (1843). This is 



allied to the two preceding species, but may be distinguished by 

 its yellow-haired scutellum and black cheeks and peristoma. It is 

 separated from latifasciatus by its abdominal bauds being straight 

 behind instead of notched. It is found in similar situations to 

 the last, also rarely. 



10. Latifasciatus, Macquart, Dipt, du Nord de France, 94, 28 S (1827). 

 This species was described as affinis by Loew in the Isis for 1840, 

 and in 1849 the male was again described by Zetterstedt as excisus, 

 and the female as ahhrcviatus* The latifasciatus of Macquart has 

 hitherto been considered a doubtful synonym of corolla, but the 



• And also by Rondani (Dip. Prod. Ii, 153), in 1857, eajlavicept.-^. H. V. 



