hese,' says Sir
William, 'gradually grow fainter and less distinct as they reach the
top of the beds, which would be the margin of drier sands nearer the
land.' He adds: 'In several instances, the tracks on one slab which we
consider to have been impressed at the same time, are numerous, and
left by different animals travelling together. They have walked
generally in a straight line, but sometimes turn and wind in several
directions. This is the case in a large extent of surface, where we
have tracks of above thirty feet in length uncovered, and where one
animal had crossed the path of a neighbour of a different species. The
tracks of two animals are also met with, as if they had run side by
aide.'

With regard to the nature of the evidence in question, Dr Buckland has
very justly remarked, that we are accustomed to it in our ordinary
life. 'The thief is identified by the impression which his shoe has
made near the scene of his depredations. The American savage not only
identifies the elk and bison by the impression of their hoofs, but
ascertains also the time that has elapsed since the animal had passed.
From the camel's track upon the sand, the Arab can determine whether
it was heavily or lightly laden, or whether it was lame.' When,
therefore, we see upon surfaces which we know to have been laid down
in a soft state, in a remote era of the world's history, clear
impressions like those made by tortoises of our own time, it seems a
legitimate inference, that these impressions were made by animals of
the tortoise kind, and, consequently, such animals were among those
which then existed, albeit no other relic of them may have been found.
From minute peculiarities, it is further inferred, that they were
tortoises of different species from any now existing. Viewing such
important results, we cannot but enter into the feeling with which Dr
Buckland penned the following remarks:--'The historian or the
antiquary,' he says, 'may have traversed the fields of ancient or of
modern battles; and may have pursued the line of march of triumphant
conquerors, whose armies trampled down the most mighty kingdoms of the
world. The winds and storms have utterly obliterated the ephemeral
impressions of their course. Not a track remains of a single foot, or
a single hoof, of the countless millions of men and beasts whose
progress spread desolation over the earth. But the reptiles that
crawled upon the half-finished surface of our infant pla