BY FREDERICK A. A. SKUSE. 19 



small kinds. All the Cecidomyidce described in this paper Imve 

 been collected by Mr. jNIasters and myself, chiefly in the environs 

 of Sydney ; but we have made numerous excursions to the Blue 

 Mountains, the Hawkesbury district, the Illawarra district and 

 other parts, all, with a single exception, within 40 miles of 

 Sydney. It would have been difficult not to discover new 

 species, for only three had been previously described;* but I 

 was surprised to find such an abundance of foruis, as it has 

 taken only a very short time to bring the total up to 95, 

 This I believe to be only a small fraction of the species of 

 the group occui'ring in an exceedingly limited area ; the number 

 inhabiting New South Wales, not to say the whole of Australia, 

 must be enormous. Other families seem correspondingly to abound 

 in species, and, judging from the comparative abundance of this 

 and other large orders of insects, the Diptera of Australia cannot 

 I think fall short of ten thousand. 



I much regret that with my descriptions of the gall-gnats I 

 have been aVjle to add the life-histoiy of but a solitary species, and 

 that only imperfectly. Although I regard the descriptions of little 

 value apart from the observation of the haV>its of the insect, 

 especially in its larval state, I do not think that should deter me 

 from making this commencement, or from jtublishing what I have; 

 for I hope that, when once a start has Ijeen made, it may induce 

 others, who will now be enabled to form some conception of the 

 amount of work there is to be done, to take an interest in the 

 subject, and to come forward to aid in its elucidation. To determine 

 the life-liistory of each species of the gall-gnats I now describe, 

 means a considerable amount of careful work, and may take me 

 some time. I should Ik; very glad to receive specimens of Diptera, 

 or portions of malformed plants possiljly infested with the larva; of 

 Cecidomyidffi, from all parts^of the country, and hope that members 

 of this and other similar scientific societies will do all in their 

 power for the furtlierance of thi.s interesting ])ranch of uaturul 

 history. The following directions if propeily carried out are 



•III " Uciae der Novara " Dipt. t)y Dr. T. K. Scliinur. 



