,02 [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 rilesii 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 rihesii 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 nitidicollis, 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 bands 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 ^ (1827). 
This species was described as ajinis by Loew in the Isis for 1840, 
and in 1849 the male was again described by Zetterstedt as excisus, 
and the female as abhreviatus* The latifasciatus of Macquart has 
hitherto been considered a doubtful synonyni of coroV.w, but tjbe 
* And also by Rondani (Dip. Prod, ii, 153), in 1857, Asflaviceps.—d. H. V. 
