Page:VCH Essex 1.djvu/215

 INSECTS Wanstead, N. viscerella at Colchester and Wickham Bishops, N. catbar- ticella at Danbury, N. septembrella is plentiful at Colchester, and N. intimella has occurred at Witham. N. subbimaculella^ N. trimaculella, N. quinquella and N. Jioslactella occur frequently at Colchester. N. salicis, N. microtheriella, N. plagicolella and N. tityrella are common. N. malella has been found at Walthamstow, N. angulifasciella at Colchester, and N. rubrvora has been taken in the county by Mr. Warren. N. marginicolella, N. alnetella and N. aurella are common. N. regiella has been obtained at Brentwood and Colchester, N. puherosella has been bred from Epping Forest larvae by Mr. E. R. Bowles. Trifurcula immundella has been captured at Wanstead by Mr. Warren. DIPTERA Flies The Diptera are for the most part small or moderate sized insects with two fully developed membranous wings and two inconspicuous haltares or balancers situated where other insects are provided with hind wings. The order is extremely numerous in species, many of which are so excessively prolific and so ubiquitous that everybody is of necessity more or less acquainted with some of them, though they have been hitherto so little studied in this country that few British entomologists know much about them. In recent years a small number of earnest workers have been endeavouring to bring about a more satisfactory condition of things, and with the commencement of the new century Mr. Verrall, who is our chief authority, has brought out the first volume of what promises to be a fine work on the order ; so that it is to be hoped that before long we may be able to give a better account of it than we are at present. The Diptera have been painted in anything but alluring colours hitherto, and even Professor Westwood, from whom they might have expected better treatment, condemns them root and branch ; for in his famous Introduction to the Modern Classification of Insects he says that ' while their size entitles them to small consideration, they have slender claims to our notice on the score of beauty, their forms are inelegant and their manners and customs atrocious and disgusting.' While some species of Diptera are undoubtedly harmful to us or to our belongings there is another side to the question, since among them are many which render us essential service as scavengers in the removal of putrefying substances, as checks upon the undue increase of other insects, as fertilizers of flowers and in a variety of other ways. Nor is the statement that they are devoid of elegance of form or beauty of colouring to be allowed to pass without challenge, seeing that many among them are brilliantly coloured and extremely beautiful. On the continent, and to a limited extent in this country, it has been the i 177" 23