a Genus of Dipterous Insects. 311 
tantüm sub nervo interno paulló obscuriores sunt, pone medium fascia 
hyalina irregularis basin versus arcuata exstat; etiam ante apicem 
alarum fascia altera feré recta hyalina apparet. Pedes fulvescentes, fe- 
moribus anticis in omnibus æquè subincrassatis ; tibiis anticis piceis tar- 
sisque subfuscis, femoribus 4 posticis ad apicem inermibus et obscuriori- 
bus; tibiis tarsisque etiam obscuris. 
This beautiful species was collected in great numbers in India by Lieut.-Col. 
W. H. Sykes, F.R.S., &c., in honour of whom it has been suggested to me by 
Mr. G. R. Gray that it ‘should be ESI gnaU a suggestion which I have © 
much pleasure in adopting. 
The former gentleman has kindly furnished me with the following notice 
respecting the habitat and habits of this species. 
* Habitat. The hill fort of Hurreechunderghur in the western ghauts of the 
. Deccan, at an elevation of 3900 feet above the level of the sea. Lat. 
19° 23' N., long. 73° 40' E. 
“ The insect affects chasms or ravines in the lofty woods which encircle the 
mountain in belts in various places. Where the sunbeams occasionally pierce 
the woods and fall upon isolated or salient rocks in the above localities, they 
are seen in myriads, either poising themselves in the rays, or reposing on the 
spots on which the rays fall.” 
Species 21. Diopsts (SPHRYRACEPHALA) BREVICORNIS. Say. 
Tas. IX. Fig. 20. 
D. nigra, obscura, antennis pedibusque ferrugineo-flavidis, alis fascià apiceque 
fuscescentibus, pedunculis oculiferis brevissimis. 
Long. corp. lin. 24 9. Wied. ths of an inch. Say. 
Habitat in Pennsylvania Americ Borealis. Say. In Mus. Say, Wiedemann. 
Diopsis brevicornis. Say, in Journ. Acad. Nat. Sciences, vol. i. 1817, p. 23. 
Achias brevicornis. Say in litt. 
Diopsis brevicornis. Wied. Auss. Zweifl. Ins. vol. ii. p. 563. No.8. Illustr. Gen, 
Achias, pl. 2. Griffith, Transl. * Règne Animal,” No. 34. p. 774. pl. 62. 
Jig. 2 
Sphryracephala brevicornis. Say, American Entomology, vol. iii. pl. 52. 
