18 DIPTERA OF AUSTRALIA, 



and perseverance, and, moreover, be prepared to devote particular 

 and exclusive attention to his subject. There are some entomo- 

 logists, however, who are not disposed to entirely concentrate their 

 attention on a single order, though even a genus alone would 

 possibly entail ample employment for an average lifetime. 



In 1864 the total number of known Australian Diptera was 

 estimated by Dr. Schiner at 1056 species, including many collected 

 by Mr. Frauenfeld in the neighbourhood of Sydney during the 

 " Novara '" expedition. Since that time very few have been 

 added. A considerable number out of the total have been 

 described by Walker in the British Museum Catalogues, but it is 

 doubtful if many of the descriptions will prove of the slightest 

 value. I believe the same author also in the year 1856 described 

 several in the "Insecta Saundersiana," a work privately printed, 

 now scarce and out of print, and which I have been unable to .see. 

 A large number were described by Macquart in his " Dipteres 

 Exotiques nouveaux ou peu connu.s," and its five supplements 

 appearing between 1838 and 1855; but the descriptions are 

 drawn up carelessly, and most of them are little better than those 

 of Walker. There are besides these, other descriptions of detached 

 species by various authors. Our acquaintance then with the 

 Dipterology of this Continent is in a mo.st unsatisfactory con- 

 dition; the descriptions are scattered and many of them worthless; 

 and, far from advancing science, are calculated to create nothing 

 but disorder. 



The present paper is the first contribution towards a work on 

 Australian Diptera, in process of pi-eparation by myself, to appear 

 from time to time in monographs of families. The materials will 

 be derived principally from the rich collection of the Hon. William 

 Macleay, in which I hope the types of all species I shall describe 

 will be found, as it would be of great value for reference, with other 

 advantages, to have all the types contained in one great central col- 

 lection; but this need not dissuade correspondents from lending me 

 specimens for description. I hope to add largely to the number by 

 my own collecting, particularly among the Cecidomyidae and other 



