Natural History: Mammalia/Edentata
ORDER IX. EDENTATA.
(Toothless Animals.)
The name by which this Order of Mammalia is distinguished must not be too literally understood. It was applied by Baron Cuvier, with strict reference to the incisor teeth, which are never present in these animals. Of several of the genera, however, (those constituting the Family Myrmecophagadæ) the term is descriptive in the fullest sense, they being totally deprived of teeth; and in those which possess these organs they are peculiar in their construction, being formed without a neck, and destitute of enamel.
Another character of these animals is derived from their nails or claws, which are of great size and strength, more or less hooked, generally sheathed, and directed downwards. For the most part the claws constitute a powerful digging apparatus, used either for the purpose of burrowing in the ground, or tearing away the earthen structures of various insects; or else they are so deflected as to form hooks by means of which the animal clings to the branches of a tree while devouring its fruit or leaves.
As animals of much diversity of form and habits are associated together in the present Order, the group was at one time supposed to be more convenient than natural; but recent discoveries in rapid succession of enormous fossil animals in South America have greatly increased our acquaintance with this Order, and supplied links of connection by the means of which the existing genera are bound together in a strong and well-defined relationship. Of all these animals none appeared to deviate more in structure and habits from all other quadrupeds than the slow-moving and climbing Sloths. But with the advantage of our present knowledge of the extinct Megatherioids, those anomalous creatures, which were formerly believed to be a very restricted and aberrant group, are now recognised as the small remnant of an extensive tribe of leaf-eating and tree-destroying animals, the larger extinct species of which, with their gigantically-developed but modified unguiculate (or clawed) structure, formed the lowest grade of Mammalia furnished with claws.
The Order before us is no less restricted in geographical distribution than peculiar in structure. With one or two trifling exceptions, it is confined to South America, which continent was also the great home of the extinct species.
We may consider the Edentata as containing four Families, Bradypodidæ, Megatheriadæ, Dasypodidæ, and Myrmecophagadæ; of these the second in the enumeration exists only in a fossil state.