CATALOGUE OF THE DIPTEROUS INSECTS COLLECTED AT SINGAPORE AND MALACCA BY MR. A. R. WALLACE, WITH DESCRIPTIONS OF NEW SPECIES. BY FRANCIS WALKER, ESQ., F.L.S. [_From the_ JOURNAL _of the_ PROCEEDINGS _of the_ LINNEAN SOCIETY _of_ LONDON, March 1856.] Catalogue of the Dipterous Insects collected at Singapore and Malacca by Mr. A. R. WALLACE, with Descriptions of New Species. By FRANCIS WALKER, Esq., F.L.S. [Read January 15th, 1856.] Mr. A. R. Wallace, so well known for his natural-history researches in the valley of the Amazons, and for the extensive and valuable collections sent home by him from that portion of South America, has now turned his attention to the eastern world, and is actively investigating the natural history of the East Indian Islands, after having spent some months on the Malay Peninsula. A large portion of Mr. Wallace’s entomological collections pass into my hands, and being desirous of making his labours scientifically useful, I have requested Mr. F. Walker, who has such an intimate knowledge of the insects belonging to the order _Diptera_, to draw up the following catalogue of the dipterous insects discovered by Mr. Wallace at Singapore and Malacca. My object in so doing is to establish a kind of starting-point for tracing hereafter, when all Mr. Wallace’s collections shall have come to hand, the geographical distribution of the _Diptera_ in the very interesting portion of the globe which Mr. Wallace is now investigating with such indefatigable zeal. Singapore and Malacca, at the extremity of the Malay Peninsula, are well placed for carrying out the purpose I have in view, being in connexion northwards through the Burman Empire with the expanded continent of Asia, and southwards in close approximation with that archipelago of splendid islands which run in a chain to the north coast of Australia, and send off a branch northwards through the Philippine Islands to the coast of China, touching there again the mainland of Asia. The present catalogue will be followed very shortly by one detailing the species of _Diptera_ discovered in Borneo, the materials for which are now nearly all in this country, and other catalogues will follow until Mr. Wallace’s discoveries in the _Diptera_ are exhausted. That Mr. Wallace will be able to visit all the islands of the Indian Archipelago is not to be expected; but still, his plan of exploring those which have been but little examined in a natural-history point of view, will open up a large amount of information, which, when combined with the labours of other naturalists who have been working in the same districts, will give sufficient facts for laying down some laws on the geographical distribution of the insects belonging to the Order