6 MR. r. WALKER ON THE DIPTERA 



very remarkable on account of the development of tlie scutellum, 

 whereby these flies have the semblance of beetles. Their range 

 extends from Hindostan through the archipelago to the Philippine 

 Isles. 



Ortalides. — This subfamily is remarkable on account of the 

 great variety of its forms, the beauty of its colours, and the 

 elegant markings on the wings of many species. Thirteen new 

 genera have been established on the insular species — Xangelma, 

 Xiria, Poticara, Mystia, Callantra, Aragara, SopJiira, Rioxa, Va- 

 lonia, Brea, Adrama, Bolyura, and Strumeta. A few of the other 

 genera require some notice. A species of OxycepTiala inhabits 

 Ceram ; but elsewhere the genus is only known to occur in North 

 America. Lamprogaster is abundant in Australia; and the species 

 of it in Malacca, Singapore, and some of the isles exhibit a re- 

 semblance to the Australian fauna. A few of the insular species 

 are very remarkable on account of the great breadth of the head ; 

 and they form the genus Zygcenula of Doleschall, or Pterogenia of 

 Bigot. The genus Dacus abounds in the isles ; and several of the 

 species, like the La/phrice, are very closely allied to each other, and 

 have much resemblance to the species of Hindostan and of Ceylon. 

 The very extraordinary genus Achias attains its greatest develop- 

 ment in Aru : some future investigation may lead to the discovery 

 of the use of the long petioles on which its eyes are seated. 



Piopsides. — The singularity of the eyes of Piopsis has been too 

 often described to require any notice here. The genus extends 

 from Africa to the Philippine Isles. 



Sepsides. — The genus Golohata is very generally distributed, and 

 is rather numerous in these isles ; and the species, though natives 

 of widely separated regions, have much mutual resemblance. 

 Some of the species of Sepsis have a great likeness to the British 

 species, which occur now and then in immense swarms. The 

 genus Angitula was established on the female of Elaphomyia, 

 Saunders {Phytalmia, Gerstacker). The female was transmitted 

 to England long before the horned male of this most peculiar 

 genus was known. The typical ElaphomyicB are not mentioned 

 in the list, as I have not described them ; but the one species here 

 recorded difi'ers widely from the others, and I have transferred to 

 it the generic name PJiytahnia. 



Psilides. — The species are few in number, but contain four 

 new genera — Ccenurgia, Texara, Seraca, and Gohrya. 



The known species of the Plwridce, like those of the preceding 

 group, are almost wholly European, and only two have been found 

 in the archipelago. The Hippoboscidce. require no notice. 



