Page:Natural History (1848).djvu/239

Rh 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&#59; of these the second in the enumeration exists only in a fossil state.

Until recently, naturalists laboured under much ignorance of the natural habits of these strangely formed animals: and hence rash and unfounded