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 INSECTS ally strongly represented in a county which contains so much grazing land as ours. The larger and more robust species seem to be found more freely in the woods and marshes towards the coast than further inland, but the pertinacious ' clegg,' Htematopota pluvialis^ and the brilliant eyed Cbryiops ceecutiens have a wider distribution. Among the Asilidce the rare Dioctria reinbardi has occurred at Colchester, and the large and voracious Asilus crabroniformis, which preys upon grasshoppers and other insects, is sometimes far from scarce in the autumn, especially in pastures where horses are feeding. Pbilonicus albiceps is a local coast species which is not uncommon on the St. Osyth sands. The Bombylidee are represented by Anthrax paniscus and Bombylius discolor and B. major. The Anthrax is a coast species not often seen and still less frequently captured, as it is an extremely wary insect. The two species of Bombylius called ' Unicorn-flies,' because of the extreme length of the proboscis, may frequently be noticed hovering before primrose and other flowers, or poised in the air making a loud humming noise with their wings, which vibrate so rapidly that their motion is hardly perceptible. In the larva state they are parasitic on the larvae of bees of the genus Anthophora. The extensive family Syrphidae comprises many of our largest and most brilliantly coloured native Diptera. Some of them are robust insects bearing a strong superficial resemblance to Humble-bees. The typical genus Syrphus contains many common species ; in the larva state they prey upon aphides, vast numbers of which are devoured by them. S. umbellatarum and S. tricinctus are scarce, and S. eucbrotnus and S. tri- angulifer very rare. Among the more notable members of other genera deserving of special mention are the fine Xantbandrus comtus^ the rare Didea alneti and D. fasciata D. alneti was added to the British list from a specimen taken at Colchester in 1893. Volucella inftata and V. inanis, two fine and very local species, are occasionally met with in some of our woods. The extremely variable Merodon equestris, at one time considered a great rarity, is rapidly becoming much too common, as many local bulb growers are discovering to their cost, large numbers of their finest narcissus and other bulbs being devoured by its larvae. The handsome genus Criorrbina is generally well represented at May blossom and raspberry and bramble flowers in certain favoured spots. The curiously constructed Conopidee or Wasp-flies are generally well in evidence in the late summer among composite flowers, and several of the species seem to be commoner in the Colchester district than in other parts of England. The Muscidtz which in the list that follows are placed in accord- ance with Mr. Austen's arrangement of the new collection in the National Museum include a number of species parasitic on the larvae of the Lepidoptera, and as some of them are excessively numerous in 179