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 



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