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 INSECTS of the town but also the sea coast between the mouth of the Colne and Walton-on-the-Naze. Among the more interesting species the Great Wood Ant (Formica rttfa) may be mentioned, for though excessively abundant in some of our larger woods, it is worthy of notice for the important part it plays in the destruction of other insects. Sometimes about the end of May the caterpillars of certain moths occur in such prodigious numbers that they completely strip the oaks and other large trees, and then descending upon the underwood speedily effect a similar clearance there. Not long ago the High Woods at Colchester were for a time so denuded of their leaves at the beginning of June that they appeared almost as bare as they had been during the previous winter, but there was one corner, which at a distance seemed to be marked off from the rest by a sharp boundary line, within which the foliage had not suffered. Closer investigation revealed the fact that the ground under the trees was covered with ants, multitudes of which were busily engaged descending the boles with caterpillars in their mouths or ascend- ing them for fresh burdens. The House Ant (Monomorium pbaraonis), a very minute species, is exceedingly troublesome in those houses in which it effects a settlement, as some Colchester householders can testify. Mr. Gervase F. Mathew also reports it as a pest in houses at Dovercourt. The rare Ponera punc- tatissima has been found in a bakehouse at Colchester ; and another ant worthy of mention is Solenopsis fugax, which lives in galleries in the walls of other ants' nests. Mr. F. Smith took this at Southend. Mutilla euro- peea is a very handsome insect, which is parasitic in the nests of humble bees ; it is always scarce, but the apterous female may sometimes be found on our coast sands, while the winged male is occasionally captured on umbelliferous flowers. Methoca ichneumonides and the scarce Pompilus unicolor are also reported from Southend by Mr. F. Smith, while P. bicolor^ P. comobrinus, P. minutulus and P. ivesmae/i, which, according to Mr. Saunders, ' are among the desiderata of most of us,' are found in the Colchester district, where also Pseudagenia carbonaria (punctum) and Agenia hircana may be occasionally met with. Tachytes unicolor has only been found on the coast, where hitherto it has apparently been confined to a patch of sand a few yards square. Ceratophorus morio is extremely rare, only three specimens having so far been met with ; and Mimesa equestris and M. dahlbomi have hitherto proved as scarce here as in other parts of the country. Gorytes campestris is an uncertain insect, and some years may be sought for to little purpose, but in 1900 it was found in larger numbers than usual on umbelliferous flowers. Hoplisus bicinctus, a very beautiful and elegant species, is apparently also local and rare, few collectors having ever met with it, but it may sometimes be found run- ning over leaves in August ; while Nysson frimacu/afus, another scarce species with a similar habit, may occasionally turn up if Hoplisus is looked for in vain. Didineis lunicornis has twice been captured at Col- chester, and the very rare Philanthus trlangulum is recorded from Snares- brook by Mr. F. Smith. Cerceris ornata in recent years seems to have 99