emain a day at Buree; and I therefore
determined on a visit to the limestone caves, by no means the least
remarkable feature in that country. The whole district consists of trap
and limestone, the former appearing in ridges, which belong to the lofty
mass of Canobolas. The limestone occurs chiefly in the sides of valleys
in different places, and contains probably many unexplored caves. The
orifices are small fissures in the rock, and they have escaped the
attention of the white people who have hitherto wandered there. I had
long been anxious to extend my researches for fossil bones among these
caves, having discovered during a cursory visit to them some years before
that many interesting remains of the early races of animals in Australia
were to be found in the deep crevices and caverns of the limestone rock.
How they got there was a question which had often puzzled me; but having
at length arrived at some conclusions on the subject, I was now desirous
to ascertain, by a more extensive examination of the limestone country,
whether the caves containing the osseous breccia presented here similar
characteristics to those I had observed in Wellington Valley.

OSSEOUS BRECCIA.

The first limestone we examined had no crevices sufficiently large to
admit our bodies; but on riding five miles southward to Oakey creek we
found a low ridge extending some miles on its left bank which promised
many openings. We soon found one which I considered to be of the right
sort, namely a perpendicular crevice with red tuff about the sides. Being
provided with candles and ropes we descended perpendicularly first, about
six fathoms to one stage, then obliquely, about half as far to a sort of
floor of red earth; Mr. Rankin, although a large man, always leading the
way into the smallest openings. By these means and by crawling through
narrow crevices we penetrated to several recesses, until Mr. Rankin found
some masses of osseous breccia beneath the limestone rock but so wedged
in that they could be extracted only by digging. Unlike the same red
substance at Wellington Valley where it was nearly as hard as the
limestone, the red calcareous tuff found here was so loose that the mass
of bones was easily detached from it; but none of them were perfect,
except one or two vertebrae of a very large species of kangaroo. Pursuing
this lode of osseous earth we traced it to several other recesses and in
the lower side of an indurated mass (the upper part h