CLINTON GROUP. 
35 
them should have been numerous, but only that the conditions should have been favorable for 
their preservation. Therefore in looking at these and the other trails, we are not to regard the 
paucity or abundance of any particular class in order to account -for their having been made. 
Throughout all the other strata, there are probably few situations where the conditions have 
been such as to preserve similar markings if made. It required not only the yielding material, 
but that it should be so exposed as to become partially hardened previous to the deposition of 
another layer upon it. We have in this group all these conditions; and therefore such markings 
as, under other conditions, would have been obliterated; are here preserved. 
PLATE XV. Figs. 1, 2, 3, 4, 5, 6. 
Several of the tracks represented upon this plate are distinctly tridactyle, or even present 
four and five distinct radiating impressions as of toes Or claws. The sand seems, not as if pressed 
by a foot, but as if drawn backwards, and the impression thus produced leaves a small elevation 
or knob of sand behind it. Others present only a simple pit with an elevated point of stone 
behind, leaving no marks like toes. 
Fig. 1. The small fragment of stone figured presents a surface marked by about six distinct 
tracks, each one showing the radiating impressions like toes very clearly. Parallel to these are 
three deep single tracks, having no marks of toes. Almost in the same line is a row of shallow 
oblique cuts, also without marks of toes, but which unfortunately are not represented in the 
figure. The exact parallelism of the two ranges, though of different character, induces a belief 
that they were made by the same animal. The range of tracks at the right hand, which escaped 
the observation of the artist in the figure, may have been partially obliterated after being made, 
as they now lie in a kind of depression or channel in which water flowed ; while those on the 
left hand, preserving the impression of toes, are on a slightly more elevated surface. 
The same specimen is marked in other parts by tracks less distinct than those given, but 
nevertheless clearly due to impressions made in the soft sand. 
Fig. 2. This figure is from a specimen marked by parallel ranges of tracks, which are more 
or less distinctly preserved throughout. A row of tracks on the left hand is preserved nearly 
entire, with the marks of toes or appendages in almost every one. The righthand range is less 
perfectly preserved, but still distinctly marked. Towards the lower side are some deep sharp 
pits, as if made by a single spine or claw. Near the base of the figure are three or four ranges 
of tracks, crossing the others obliquely. These; tracks are slightly different in their character 
from the others, but still appearing as if made by sharp spines or claws impressed into the mud 
and withdrawn, leaving sharply elevated ridges on both sides. 
Near the .centre of the specimen, the tracks are partially obliterated by another range of 
shallow pits or tracks made in a double parallel series. ; 
Fig. 3, is a part of a specimen which shows a double parallel series of tracks, all of which 
are marked by toe-like appendages, and appear as if made by two animals travelling in parallel 
lines i 
