rnalous conditions are so far from being defects,
or sources of inconvenience in the Sloth, that
they afford striking illustrations of the varied
contrivances, whereby the structure of every
creature is harmoniously adapted to the state in
which it was destined to live. The peculiarities
of the Sloth, that render its movements so awkward
on the earth, are fitted with much advantage
to its destined office of living entirely upon
trees, and feeding upon their leaves: so also, if
we consider the Megatherium with a view to its
province of digging and feeding upon roots, we
shall, in this habit, discover the explanation of
its unusual structure, and apparently incongruous
proportions; and find, in every organ, a relation
of obvious convenience, and of adaptation to the
office it had to discharge.*
It will be my present object to enter into such
a minute investigation of some of the more remarkable
parts of this animal, viewing them with
a constant reference to a peculiar mode of life, as
may lead to the recognition of a system of well
* The remains of the Megatherium have been found chiefly in
the southern regions of America, and most abundantly in Paraguay
; it appears also to have extended on the north of the
equator as far as the-United States. We have, for some time,
possessed detailed descriptions of this animal by Cuvier, Oss.
Foss. vol. 5. and a series of large engravings, by Pander and
D ’Alton, taken from a nearly perfect skeleton, sent in 1789 from
Buenos Ayres to Madrid. Dr. Mitchell and Mr. Cowper have
described, in the Annals of the Lyceum of Nat. Hist, of New
York, May, 1824, some teeth and bones found in the marshes of
connected contrivances, in the mechanism of a
creature apparently the most monstrous, and
seeming to present the most ill-assorted proportions,
that occur throughout the entire range of
the animal kingdom.
We have here before us a gigantic quadruped,
(see PI. 5, Fig. 1 ), which at first sight appears
not only ill-proportioned as a whole, but whose
members also seem incongruous, and clumsy, if
considered with a view to the functions and corresponding
limbs of ordinary quadrupeds : let us
only examine them with the aid of that clue,
which is our best and essential guide in every
investigation of the mechanism of the animal
frame; let us first infer from the total composition
and capabilities of the machinery, what was
the general nature of the work it was destined to
perform ; and from the character of the most important
parts, namely, the feet and teeth, make
ourselves acquainted with the food these organs
were adapted to procure and masticate; and we
shall find every other member of the body actthe
Isle of Skiddaway, on the coast of Georgia, which correspond
with the skeleton at Madrid. Cuvier, Vol. V. part 2, p. 519.—
In the year 1832, many parts of another skeleton were brought
to England by Woodbine Parish, esq. from the bed of the river
Salado, near Buenos Ayres: these are placed in the museum of
the Royal College of Surgeons in London, and will be described
in the Trans. Geol. Soc. Lond. Vol. III. N. S. Part 3, by my friend
Mr. Clift, a gentleman from whose great anatomical knowledge,
I have derived most important aid, in my investigation of this
animal.