oes three. It is called, therefore, ANOMOEPUS, _unequal-footed_.
These impressions are in the red shale of Hadley, and very distinct.
In some of them the lower leg is indicated, forming an impression six
or seven inches long. The feet being smaller than the legs, the
impression made by the latter is more expanded, superficial, and
broader, yet still very definite. The opinion of President Hitchcock
and Dr. Deane is, that the different impressions of five and three
toes are those of the anterior and posterior extremities of one animal,
which, from the size of the limbs, might be a frog three feet high.

On the same schist with these footmarks, are other curious
impressions. The back of the slab is almost covered with the imprints
of rain-drops. In the midst of these is a tridactylous impression,
probably of a quadruped, crossed at its root by a single depression,
nearly an inch broad, and two and a half long: this seems to form part
of another broad superficial impression of about seven by four inches,
which is probably also quadrupedal. Other parts present the
impressions of nails and worm-tracks. At the opposite end is a deep,
smooth, regular excavation, which might have been made by a Medusa.

* * * * *

GROUP SEVENTH.

The seventh group contains the impressions of the feet of Saurians or
lizards. We have a specimen of quadrupedal marks, with five toes to
each foot, about an inch long, which may have been made by these
animals. The impressions are small, but very distinct. There are
lizards of the present day with five toes, about the size of these
impressions; and these may, therefore, be set down as belonging to
this order of reptiles. Like a number of the last-named specimens,
they are in red shale.

* * * * *

GROUP EIGHTH.

The eighth group is assigned by President Hitchcock to the Chelonian
or turtle tribe. The slab bearing impressions of Brontozoum
Gracillimum has a mark about fourteen inches long and two wide, which
may be attributed to the plastron or breast-plate of the tortoise. On
the slab from Turner's Falls there is a longitudinal furrow, which
might have been made by the tail of a turtle; and in various of our
slabs are impressions which we think belong to this tribe. We shall
have occasion to notice hereafter remarkable tracks of these animals
in the old red of Morayshire, in Sc