Lo 
To these last remarks there is one exception: the 
deep impression in which the bird slipped in a lateral 
direction corresponds with an elevation on the lower 
surface, in which the impression of these toes is very 
distinctly displayed, and even the articulations. 
Moreover, one of the tracks on the inferior surface 
interferes with the outer track in the superior, and 
tends in an opposite direction, so that this last- 
described footstep must have been made before the 
other. It is also observable, that, while all the other 
tracks are superficial, this last penetrates the whole 
thickness of the slab; thus showing that the different 
deposits continued some time in a soft state. | 
On the surfaces of this slab, particularly on the 
upper, there are various marks besides those of the 
feet, some of which seem to have been made by straws, 
or portions of grass, or sticks; and there is a curved 
line some inches in length, which seems to have arisen 
from shrinkage. 
In the collection of Mr. Marsh,* there were two 
* Mr, Marsh was a mechanic of the town of Greenfield, and procured his 
subsistence by his daily labor. Being employed by Dr. Deane in obtaining 
the sandstone slabs of Ornithichnites, he acquired a taste for the pursuit, 
entered into it with extraordinary ardor, and accumulated by his own labors a 
great collection of fine specimens. He unfortunately fell into a consumption, 
and died in 1852. The collection was sold at public auction for a sum 
between two and three thousand dollars. The specimens were purchased by 
the Boston Society of Natural History, by Amherst College, and by various 
colleges and scientific associations in this country. 
