1871.] 203 
15. X. florum is rather larger (5 lines against 43), the male has also a 
short spine on the hind trochanters, the hind femora are compara- 
tively thin, the pubescence all down the edge of the fourth abdo- 
minal segment is whitish, and the base of all the tibiz is distinctly 
yellow. Of this, Mr. B. Cooke possesses a pair, and Mr. Marshall 
one very dark female, labelled Keswick. Xylota nemorum, F. is 
allied to the two above mentioned, but is distinguished by the 
unarmed hind trochanters of the male (proving it to be forum of 
Zetterstedt), by its short, stout appearance, by the squarer abdominal 
spots (proving it to be also bifasciata of Meigen), and by the thick 
hind femora (thickest of all the three); Mr. B. Cooke and Mr. 
Marshall possess the species. 
16. Plocota apiformis, Schrank: this species and genus can hardly be 
considered new to our lists, considering it is figured by Moses 
Harris from a British specimen; it has, however, never been re- 
corded since. Mr. J. C. Dale possesses a specimen. The species 
seems sparingly scattered all over Europe. 
17. Eumerus litoralis, Curtis, is only a synonym of sabulonum, according 
to aspecimen given me by Mr. J. C. Dale. 
18. Orthoneura brevicornis, Loew: there was a male of this among some 
Diptera given me by Mr. D’Orville of Exeter. 
19. Pipiza vana, Zett., is only the male of noctiluea; I caught both 
togetber abundantly at Rannoch last year. 
In addition to previous synonymy, I believe Platychirus quadratus 
of Macquart is only scutatus, and his dilatatus only peltatus; I agree 
with Malm in considering Pipiza carbonaria and stigmatica of Zetter- 
stedt to be only small varieties of P. noctilucag; Tropidia dorsalis of 
Macquart does not seem to have any distinguishing character from 7. 
milesiformis, as the difference in the form of the epistoma, which he 
relies upon, seems but very slight, and probably accidental. 
I possess several other species, principally from Rannoch, not yet 
sufficiently identified to bring forward; the present paper, however, 
adds fifteen species to my previous list, confirms two doubtful ones, and 
excludes two, making the present number of species 179, five of which 
still remain doubtful. 
The Mulberries, Denmark Hill, London, 8.E. 
