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Rh and possessing some twenty pairs of imperfectly-jointed limbs, to each of which, two claws are attached. Resembling worms in some respects, it has several features peculiarly characteristic of insects. Such are the respiratory organs, consisting of branched air-canals called trachea, ramifying through the whole extent of its body, and a pair of salivary glands for digestive purposes. It has, moreover, a pair of slime-glands, secreting a sticky substance resembling bird-lime. Thus Peripatus is the first animal in the ascending scale which has organs specially adapted for breathing air, and it stands midway between worms and insects. It is found at the Cape of Good Hope, Sumatra, Australia, and New Zealand, so that its distribution is widespread, but it is nevertheless local, or in other words the animal is confined to a small area in each of these places. In all probability it was originally widely distributed, but just as at the present day the native rat of New Zealand is being driven out by the common household rat, so Peripatus became supplanted by some stronger form, and was left in the isolated patches in which it is now found. Such distribution as this is generally found in the case of old generalized types, which represent the ancestors of existing species, and do not with any degree of nicety fit into the higher types of the present day.

Attention may here be drawn to the small maps placed near each group of animals, which give, clearly and effectively, by means of coloured patches, the regions occupied by the different species.

After Peripatus, follow in order spiders, locusts, flies, bees, and butterflies, affording many excellent examples of adaptation to the surroundings both in colouring and in form. Witness the walking-stick spider, which, by the way, is really not a spider but an insect. Its body, like a dried yellowish stick, and its legs like six spiny branches, cause it to be scarcely distinguishable from the blackberry bushes and manuka scrub, in which in New Zealand it is commonly found.

Many insects are very brilliantly coloured, others scarcely at all, while some butterflies, for example, although strikingly marked, and in a museum presenting a conspicuous appearance, are coloured and marked so completely in harmony with the leaves on which they settle, as to be with difficulty recognizable