Page:The Zoologist, 1st series, vol 1 (1843).djvu/313

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Quadrupeds.
285
as the hand, which is of considerable breadth. Next to moles, the best diggers or burrowers are found in the order to which Megalonyx belongs, especially in the armadillo family; but the different species of that genus are not all equally well provided in this respect. The best diggers are the cabassous, among which we again recognize the same characters as in the moles; a broad hand, all the digits provided with claws, very broad and nearly equal. In the Euphractus the hand is somewhat smaller, as are also the claws, although their number remains undiminished; consequently, the species of this family cannot compete with the former as burrowers. In the true armadilloes the number of digits provided with claws is reduced to four; and they are so inferior to the first described, in the faculty of digging, as to avail themselves, for the most part, of the burrows the others have excavated."—Lund, l.c. p. 159.

Dr. Lund then compares the hand of the sloth with that of the Megalonyx, showing that the latter is adapted for climbing rather than burrowing. He describes the hand of the anteaters, showing how well it is adapted for its employ of tearing open the hills of the white ants: he maintains that these animals do not burrow, and hence concludes that the resemblance of the hand of Megalonyx to that of the anteaters, by no means goes to prove, as suggested by Cuvier, that it was a burrowing animal. He next considers the enormous strength of the hinder extremities, the prodigious claw of the middle toe, and the unusually powerful tail (which he supposes to have been prehensile) of the extinct animal; and maintains that all these conditions indicate the power of climbing. It seems however to strike the author that creatures of such enormous bulk were scarcely fitted for the trees of the present day, even as we see them, and in the stately forests of Brazil; and he therefore concludes by clothing this region of monsters with a vegetation proportionably gigantic.

"In truth, what ideas must we form of a scale of creation, where, instead of our squirrels, creatures of the size and bulk of the Rhinoceros and Hippopotamus climbed up trees! It is very certain that the forests in which these huge monsters gambolled, could not be such as now clothe the Brazilian mountains; but it will be remembered, that in the former communication which I had the honour of submitting to the Society, I endeavoured to show that the trees we now see in this region, are but the dwarfish descendants of those loftier and nobler forests which originally clothed these highlands; and we may surely be permitted to suppose that the vegetation of that primaeval age was on a no less gigantic scale than the animal creation. "In the present order of existing nature, all the mammals that are appointed to live in trees belong to the smaller kinds; which seems so essential a condition, that in the families and genera containing climbers, the development of this faculty diminishes in a ratio corresponding to the increase in size of the species. Thus, in the genus Felis, the smaller species live for the most part in trees; those of an intermediate size hunt their prey on the ground, but climb with more or less activity; while the largest species of all are entirely deprived of that power. Again, in the family of apes, the existence of the smaller kinds is indissolubly linked with arboreal habits; while the