A VERY large and important order is that of the ungulates, or hoofed mammals. They may be divided into two sections, the odd-toed and the even-toed. The first division includes the rhinoceros and the horse tribes. Though these groups are widely separated from each other by many important characteristics, the intervals between them have been bridged by many forms now extinct.
The Indian rhinoceros has one horn and deeply marked folds in the skin. Like all rhinoceroses, it suggests a type of the very distant past, when such heavy, slow-thinking beasts were very common. In Africa both species, the white and the black, carry two horns. The white rhinoceros is the larger of the two—in fact, after the elephant, it is the largest living land mammal. Another point of difference is the square-shaped muzzle of the white variety, as compared with the finger-like lip possessed by the black rhinoceros.
In speaking of the ‘horn ‘of a rhinoceros, it should be stated that this is not the usual structure of horn on a bony core, as in the case of other ungulates, but is a collection of hairs, adhering together, and making a very strong and resilient substance which is, however, only loosely attached to the head.
The tapirs are gentle, inoffensive animals, inhabiting tropical forests, vegetarian in diet, with a short, flexible proboscis used for feeding. There are several South American species, which are dun-coloured, pig-like animals, many of them being aquatic in their mode of life, and usually nocturnal in habits. The Malay tapir is the largest of this family and differs strikingly in colouration, as it has a large, saddle-shaped patch of white on the back. This may be taken as a case of natural colour
protection, since it breaks up the outline of the body and makes it difficult to distinguish.
An interesting fact about the pigmentation of this animal is that it is of a free nature, and can easily be rubbed off on the hand if touched. Also the young of both the South American and Malay species do not at birth resemble their parents in marking, but in both cases are striped and spotted, thus pointing to a common ancestry. It does not take them long, however, to lose their spots and become replicas of their respective parents.