On advancing from the temperate regions to the line, we find the insects gradually increasing with the multiplicity of plants, and at length attaining the greatest size, brilliancy of colour, and variety of form in those tropical lands where moisture combines with heat in covering the ground with a dense and everlasting vegetation. Our largest insects are indeed mere pygmies when compared with their tropical relatives. We have no tiger-beetle to equal the ferocious Mantichora of South Africa, which, hiding beneath stones from the terrible glare of the sun, darts quickly from its place of concealment upon its ill-fated prey; nor a stag-beetle of the size of the Odontolabris Cuvera of China and Northern India. Our largest dung-feeding Lamellicorns look but small near the African Copris Hamadryas; and our cockchafer, though conspicuous among our native insects, is a dwarf when confronted with the Leucopholis bimaculata of India, which, if it be voracious in proportion to its size, must destroy a vast amount of vegetation in the course of its long larval existence. The Goliath beetles of the coast of Guinea, are truly deserving of their name, and in torrid America the colossal Hercules beetle attains a length of five, or even six inches. Though but little is yet known of its economy, it most likely subsists upon putrescent wood, and evidently leads a tree life, like its relations--the Elephant, the Neptune, the Typhon, the Hector, and the Mars beetles-- whose very names indicate that they are ‘first-rate liners’ in the insect world. All these beetles excavate burrows in the earth, where they conceal themselves during the day, or live in the decomposed trunks of trees, and are generally of a dark rich brown or chestnut colour. On the approach of night they run about the footpaths in woods, or fly around the trees to a great height with a loud humming noise. Resembling the large herbivorous quadrupeds by their comparative size and horn-like processes, they are still further like them in their harmless nature, and thus deserve in more than one respect to be called the elephants among the insect tribes. [Illustration: ODONTOLABRIS CUVERA.] [Illustration: COPRIS HAMADRYAS.] [Illustration: LEUCOPHOLIS BIMACULATA.] Many of the tropical dragon-flies, grasshoppers, butterflies, and moths are of no less colossal dimensions in their several orders than the giants among the beetles. The Libellula lucretia, a South American dragon-fly, measures five inches and a half in length, and the cinnamon-eating Atlas-moth of Ceylon often reaches the dimensions of nearly a foot in the stretch of its superior wings. The names of many other species conspicuous by their size might be added; but these examples suffice to show the enormous proportions attained by insects in the warmer regions of the globe.