II) I C I I N O L O G Y OF ANN AND ALE.
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CHELICHNLIS TITAN, JARD.
SoMK yciirs siiico, a bed was exposed in Corncockle Quarry, bearing magnificent Impressions of the footprints of
nil enormous animal. This wo liavo now bad removed and placcd under cover, where it can at any time be
examined. We originally supposed this to be the same impressions with those of C. gigm, probably an adult
01- a. very large specimen : but several discrepancies have appeared upon a later and more experienced exami^
nation. 'Hiis slab is 10 foot in length, and presents eiglit impressions upon the one side and seven upon the
other. These impressions do not present the smooth surface and shallow ring, but appear as simple depressions,
made by an enormous foot, tlio sand thrown up behind incheating the pushing back power of jjrogression. From
tlic weiolit of the animal, some of the soft substance has been withdrawn Avhen the foot was lifted, rendering
the bottom of the hollow irregular, and in one or two of the footprints we have traces anteriorly of what appear
to liavo been strong short toes, or separations in the anterior margin of the foot. These footprhits are from
0 to 10 in length by nearly the same in breadth ; the paeo is shghtly alternate, but the distance betwixt each
foot is not more than 7 or 8, or about a corresponding length of stride, and the animal must have been much
shorter limbed than that to which we have given the name of C. gigas. The impressions must have been made
by a heavy short-legged animal, progressing at a slow and deliberate pace. The depth of the impressions indicate
a heavy animal, wliile the width across the prints of both sides, 2.5 or 6, represent one of very large size.
This slab is the only one that has yet occurred, and so far as we are aware, is unique.
CHELICHNUS DUNCANI, OWEN.
PLATES II. III.
Tins is by far the most common impression in the Annandale Sandstones, and being sucli, was that which first
attracted the notice of Dr. Duncan, and formed the chief object of correspondence between that gentleman and
Dr. Bucldand, slabs from Corncockle Mnir being the originals of the first plates or representations of footprints
in the " Transactions of the Eoyal Society of Edinburgh" and in the " Bridgewater Treatise." These
also form the authority of the short notice of " The New Red Sandstone Tortoises" by Professor Owen, in
his " Report upon British Fossil Reptiles," read to the British Association in 1841, and where the name of
TfKtudo duncani is given in honour of its original discoverer.
I C I I N O L O G Y OF ANNANDAL E . H
"We meet witli this impression on almost every bod, in various states of preservation, according to what
had been the condition of the then sand and clayey layer that might bo superimposed. Tracks, several feet in
length, arc very frequently exposed, which give a good idea of the uniformity of pace at which the animal proceeded.
At one time there was a track of 30 feet in length laid bare, which proceeded first in a straiglit
line, and afterwards diverged in different directions, maintaining however durmg its progress the same uniformity
of pace or stride.
The general size and form of well marked impressions are nearly such as are represented on PLATES 1.
and II. The size of the footprint in these is from 1 . 5 in length to 1.2 or 3 in breadth, having an irregular
oval outline in front. The impressions of the two feet, upon cach side, follow near upon each other, the claws
of the hinderfoot pressing closc upon the sand, pressed back by the forefoot. The length of the stride, or the
distance between the toes of the forefoot and heel of the hinder, is not more than 1.5 or G. sometimes even
shorter, as if the animal had wallvcd more slowly; while the distance between the right and left paces is from
i . 5 to 2, or over the impressions, which would mdicate the width of the animal, if it possessed no overstretching
c.overing, to be somewhat about 4.5 or 5. These paces are generally marked with great regularity, as exhibited
on the left figm-e of PLATE III. This form and the general size is also represented upon PLATE I. which
exhibits a very interesting slab, a portion of one bed of 4 thickness being removed, and the track of another
animal being seen upon that below. On the right figure of PLATE III. wc have represented the impressions of
one side only very deeply indented, that have been produced by a larger sized anunal of the same species.
The footprints arc larger, and the length of the stride is 3.5, but wc are sorry not to be able to state the
width, the opposite or corresponding row of footprints being wanting.
From these and the many impressions which wc have seen and compared with the mode of progression
incident to reccnt Tortoises, wc have little hesitation in judging them to be, if not identical, ccrtaiiJy very close
in form ; and allowing this to be the ease, the average size of the animal would be from 7 to 8 or 9, by about
5 . 5 or 6 broad. The legs were short and capable only of restricted motion forwards and backwards, and would
force the animal forwards by that pecuhar pushing back action which wc see among the Tortoises, as weU as in
most of the Saurians and Batrachians. The foot has been of an irregularly oval form forwards, having five toes,
armed with strong but not sharp claws, the sole or pad perfectly soft and smooth. This softness we see very
distinctly by the texture of some of the impressions, where the upper layer has come clean and freely out,
leaving the surface to imagination, as of a fine and leathery feel. It has been shghtly und^dated, though not
divided into separate pads; but on the hindfoot there has been a distinct posterior pad or heel, while the
outer portion of the sole seemed to form another larger one, all preceded by very shght elevations of the five
toes. These pads and elevations appear, of course, as slight hollows in the impressions.