Page:Picturesque Dunedin.djvu/121

Rh On the ground-floor, at the western side, are the duck-mole and the spiny ant-eater, the first representatives of mammals. They differ greatly from the rest of mammalia, and in many respects resemble reptiles. They lay eggs, and are destitute of teeth. In many ways they differ more from the next highest sub-class of mammals, the marsupials, than any other two do from each other.

In one of the cases at the north end, is a curious example of the canine tooth, or tusk of the pig. It has grown round and entered the cheek, piercing the lower jaw just below the teeth and even entering the tongue. Such instances of teeth with persistent pulps, growing to an abnormal length, are not infrequently seen in rats and rabbits, where the teeth in one jaw have been lost, and nothing is left to wear away those in the other.

Along the eastern side are lions, tigers, and such-like animals, after which come many varieties of monkeys. The series ends with two skeletons, the one of the powerful orangutan, the other of a man, and these are worthy of comparison. The orang usually assumes a semi-erect position, and its long arms then rest with the knuckles upon the ground.

The great majority of mammals are land animals, the bat alone is aerial. A membrane stretched between its greatly elongated fingers enables it to fly, and another curious fact about it is, that when asleep it hangs by its two hind limbs, head downwards. The few mammals which live in the sea, are represented by seals, whales, and a few others. These are shown in the enclosures, and among them, the crested seal, and gigantic sea-elephant may be noticed. The lower jaw of a whale, in the same enclosure, contains teeth, whereas in other species of whales, as in the large one suspended from the top gallery, teeth are replaced by numerous plates of baleen or whalebone.

In the other enclosures are many typical skeletons, the New Zealand skeletons forming a distinct group.

At the south end is an interesting model called an index collection. It consists of an upright stem, from which rods branch off at different heights. Along the stem and branches are placed various animals representative of groups. Most of