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 INSECTS unfrequently get the blame for the blighted appearance of the aphis- infested trees on which they occur. Though of comparatively small size, they are for the most part brightly coloured. The red kinds with two or seven black spots {Coccinella bipunctata and C. septempunctata) are probably the most familiar, though Coccinella 22-puTictata, of a bright lemon colour with about twenty-two roundish black spots, is one of the most elegant ; it may be found on nettles by almost any roadside. There are probably few asparagus beds where the asparagus-beetle {Crioceris asparagi) is not to be found, both in the larval and perfect states, during the summer and autumn ; but though this beetle is usually classed amongst the ' insect pests,' it may be doubted whether its presence has any deleterious effect on the crop, except in those cases where circum- stances arise which favour its development to an abnormal extent. Though the asparagus-beetle is only about a quarter of an inch long, it is very effectively coloured ; the head, antenna and legs are blackish green, the thorax is red, the wing-cases are pale yellow with a very dark blue marking in the shape of a cross, and the whole insect shines as though it had a coat of varnish. The rose-beetle [Cetonia aurata), a broad rather flat insect about three-fourths of an inch long, of a beautiful metallic green colour with a few irregular transverse wavy whitish lines on the hind part of the wing- cases, is usually accounted a common insect, and such it undoubtedly was in this county some five-and-twenty years since, when it was to be found abundantly on various kinds of showy flowers, particularly roses and white lilies, and four or five at a time might be taken from a single head of flowers of the mountain-ash in suburban gardens around Norwich. It is however now many years since the writer saw a living example of this fine species. One of the beetles most familiar to the ordinary observer of Nature is the ' dor-beetle,' ' dumbledor,' or ' clock ' [Geotrupes stercorarius), a plump shining black insect about an inch in length, often found flying about roadways at dusk with a loud humming noise. When in full flight its steering powers appear to be defective, as it not unfre- quently comes into collision with pedestrians ; and, when the point of contact is the face, a stinging blow is the result. On the underside the black colour of the insect is relieved by metallic reflections of blue, purple, and green. When taken in the hand and forcibly detained the dor-beetle endeavours to bring about its release either by feigning death, in which case it stretches out its legs to their utmost extent in the most awkward and unnatural positions and then remains absolutely motionless for some time, or it sets up a feeble squeak, standing still and moving the hind part of its body up and down. The mechanism by means of which it produces this noise is worthy of notice. On that side of the basal joint of the hind leg which lies nearest to the body is a con- spicuous oblique ridge, the surface of which bears a number of ex- ceedingly fine transverse ridges, thus forming a sort of file, whilst the hinder edge of the cavity in which the joint works bears a fine smooth ridge ; the friction between the latter and the file when the hind III