THE HYÆNA FAMILY.[61]
This group contains the single genusHyæna, one species of which, the Striped Hyæna (H. striata), inhabits North-east Asia and Northern Africa; the others (H. crocutaandH. brunnea) inhabiting South Africa.
Externally, the Hyænas have something the appearance of extremely ugly and unattractive-looking Dogs. They are somewhat larger than a Shepherd’s Dog, and are covered with coarse bristly hair, short over the greater part of the body, but produced into a sort of mane along the ridge of the neck. The mode of progression is entirely digitigrade, the legs having much the same proportion as in an average Dog, except for the fact that the hind legs are shorter than the fore legs, so that the body slopes from the withers to the haunches. The claws resemble those of the Dog in that they cannot be retracted in sheaths of skin: here, therefore, we have a great and marked difference from all the Cat tribe.
SKULL OF HYÆNA.
SKULL OF HYÆNA.
TEETH OF HYÆNA.a, First lower molar.b, Last upper premolar.
TEETH OF HYÆNA.
a, First lower molar.b, Last upper premolar.
The tail is bushy, the snout long, but blunt, giving the beast a snub-nosed appearance and a horridly vulgar expression, quite different to that of most of his relatives. The long-nosedness is partly, however, only a matter of external appearance, for the skull, although nothing like as short as a Cat’s, is yet very far from being as long as that of a Dog or a Civet, and it is still more Cat-like in the immense width of the cheek-arches, and the great development of bony ridges for the attachment of muscles. The great longitudinal ridge on the top of the skull is indeed far larger than in even the Lion or Tiger, and forms a great shelving crest, like that of an old-fashioned helmet. As we have already mentioned, this ridge is for the attachment of the great cheek muscles which close the jaw-muscles which, in the Hyæna, are of such power, that the animal’s favourite way of attacking Dogs is to bite their legs off, and one of its choicest titbits is the marrow of bones, which can only be obtained by cracking the bone across, as we should crack a nut. Any one who has examined a Horse’s or an Antelope’s thigh-bone will have some notion of the power of jaws capable of smashing such a tough morsel.
LOWER JAW OF HYÆNA.
LOWER JAW OF HYÆNA.
But something more is required than strong muscles for work such as this; and the Hyæna isfurnished with a set of tools which, when worked by such mighty power, are simply irresistible. The large grinding-teeth, instead of the scissor-blade form they have in the Cats, have great conical crowns, the base of the cone being belted by a strong ridge which defends the subjacent gum (see figure on preceding page). One has only to look at these teeth to see their perfect adaptation to their purpose. Sir Richard Owen remarks, “An eminent civil engineer, to whom I showed the jaw of a Hyæna, observed that the strong conical tooth, with its basal ridge, was a perfect model of a hammer for breaking stones for roads.”
The canines of the Hyæna are proportionally much smaller than in theFelidæ, and the outermost incisor—that nearest the canine—is much larger than in the Cats, so that it approaches towards the canine in size. This, as we shall see, is even more the case in the Dog.
Then, the number of the teeth is different; the Hyæna is a less specialised animal than the Cats, that is, departs less from the average structure of a Mammal, and, in correspondence with this, we find that its jaws are longer and its teeth more numerous; it has, in fact, one more premolar, or false grinder, on each side of each jaw, bringing the total number of teeth to thirty-four, instead of thirty. (See p. 13.)[62]
SKELETON OF HYÆNA.
SKELETON OF HYÆNA.
In speaking of the Cat family, we mentioned that the characters of the floor of the skull, and particularly of the swollen, bulb-likebulla tympani, were of great importance in determining the position of an animal in the series. Now thisbullain the Hyæna is large and rounded, as in Cats, but differs in the fact that it is not divided by a bony partition into two compartments. The external opening of the cavity, too, is quite flush with its outer wall, and the clamp of bone (see figures onpp. 11and79) is quite close to its hinder wall.
In these characters, as well as in certain matters of internal structure, such as the presence of a smallcæcum, or “blind-gut,” the Hyænas approach to the Cats and Civets, being connected with the latter group by the curious Aard-Wolf. In other respects they approach the Dog family, their nearest ally in that group being the Cape Hunting Dog.[63]