COLEOPTEROUS INSECTS. 
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length. The colour of the upper surface is a fine 
blue, inclining sometimes to green. The thorax is 
nearly twice the width of the head, truncated be- 
fore and behind, and somewdiat heart-shaped ; the 
surface rough and granular. The elytra are oval 
and convex, covered with large tubercular points, 
which are arranged nearly in straight lines. The 
under side of the thorax and the sides of the abdo- 
men are tinged with greenish blue ; the other parts, 
as well as the legs, are black. 
The insects to which the generic appellation of 
Carabus is now restricted is of very considerable 
extent, including about 170 well-ascertained species. 
They are generally of considerable size, and most 
frequently of a dark colour, glossed with blue or 
purple. Many of them, how r ever, are of the bright- 
est metallic hues, and deserving of being ranked 
among the most ornamental of European beetles. 
Such are C . rutilans, an inhabitant of the Pyrenees, 
and our own C. nitens y found in heathy districts, 
where the soil is formed of peat, in many parts of 
Scotland and the north of England, which scarcely 
yields to any exotic insect in the brilliancy of its 
lustre. The principal seat of the Carabi is within 
the temperate zones; they become rare in very 
warm countries, and seem to disappear altogether 
within the tropics. They are most abundant in 
the old world, but a few have likewise been observ- 
ed in the northern and southern extremities of Ame- 
rica. Britain possesses about sixteen species, and 
