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 A HISTORY OF KENT Mr. Lewis has also found eight galls formed by the following Cynipidx in Kent : — Xestophnes potentillae, Cam. Rhodites rosae, Htg. Aulax glechomse, Htg. — eglanteriae, Htg. Diastrophus rubri, Htg. — nervOsus, Curt. ENTOMOPHAGA Ichneumori-Jiies, etc. This is by far the most extensive and perplexing section of the Hymenoptera. It is also the one that has been studied least, and it is safe to say that a large number of the species occurring in Kent have not even been described. This section therefore presents an exceptionally interesting and promising field for entomological research. The Entomophaga are parasites of the most pronounced kind ; they deposit their eggs inside the bodies of other insects, and the larv£e feed on the living tissues, avoiding the vitals until the fleshy portions have been devoured. For this purpose the female is armed with a sting-like ovipositor, which varies in length. In some of the groups the ovipositor is visible — sometimes it is long — but in others it is concealed. The Entomophaga prey mostly upon common species of insects. A few of them confine their attacks to single species, but the majority feed on a variety of species, and attack them in the larval stage. It is usual for a number of specimens to inhabit the body of one caterpillar, and the parasites are almost sure to cause death eventually, although cases are on record in which the victim has arrived at the perfect stage. The victims of many of the Entomophaga are destructive to crops, and were it not for the attacks of the parasites the damage they might do would be very great. The ichneumon-flies are therefore of the greatest economic value, and few insects have a more important part to play in maintaining the balance of nature. The species vary in length from about an inch to less than a millimetre. A large number of the species are exceedingly minute, and can only be properly examined under a powerful lens. The Entomophaga have been collected to some extent in Kent, and several interesting species have been taken. One or two of these will be mentioned in the following brief notice of each of the main groups. Ichneutnonida. This is one of the largest groups, and probably over a thousand species exist in the county, of which only about 300 have been recorded. Relative to those of other groups the majority of the species are large. They are slender insects. Many of them are black with yellow and red markings, and the antenns and legs are more or less yellow. The large brightly-coloured species chiefly belong to the extensive group of which the genus Ichneumon, L., is the type. Rhyssa persuasoria, L., has occurred lately near Dover ; it destroys the larvs of Sirex gigas. This ichneumon-fly is nearly an inch in length, and the ovipositor, which is used to drill holes into trees infested with the Sirex larvas, is itself longer than the body. Braconidce, This is a moderate-sized group, of which probably over