any of the collections,
respecting the diluvial deposits of Australia: a class of phenomena which
is of the highest interest, in an island of such vast extent, so very
remote in situation, and of which the existing animals are so different
from those of other parts of the globe. It is remarkable, also, that no
limestone is among the specimens from the northern and western shores,
except that of the recent breccia; and although negative conclusions are
hazardous, it would seem probable, from this circumstance, that limestone
cannot be very abundant or conspicuous at the places visited. No eruptive
mountains, nor any traces of recent volcanic eruption, have yet been
observed in any part of Australia.

5. The recent calcareous breccia, of which a detailed description will be
found in the subjoined list of specimens, is one of the most remarkable
productions of New Holland: It was found, during the expedition of
Commodore Baudin, to exist throughout a space of no less than twenty-five
degrees of latitude, and an equal extent of longitude, on the southern,
west, and north-west coasts;* and from Mr. Brown's specimens it appears
to occur also on the shores of the Gulf of Carpentaria. The full account
which M. Peron has given of this formation, sufficiently shows its
resemblance to the very recent limestone, full of marine shells, which
abounds on the shores of the Mediterranean, the West India Islands, and
in several other parts of the world: And it is a point of the greatest
interest in geology, to determine, whether any distinct line can really
be drawn, between those concretions, unquestionably of modern formation,
which occur immediately upon the shore; and other calcareous
accumulations, very nearly resembling them, if not identical, both in the
fossils they contain, and in the characters of the cementing substances,
that are found in several countries, at considerable heights above the
sea.

(*Footnote. Voyage 2 page 168, 169 to 216 etc.)

Dr. Buckland has described a breccia of modern formation, which occurs
upon the shore at Madagascar, and consists of a firmly-compacted
cream-coloured stone, composed of granular fragments of shells,
agglutinated by a calcareous cement.* The stone of Guadaloupe, containing
the human skeletons, is likewise of the same nature; and its very recent
production cannot be doubted, since it contains fragments of stone axes,
and of pottery.** The cemented shells of Bermuda, described by Capta