Mineralogy and Geology. 125 
I have discovered the foot-prints, in bas-relief, of a reptilian quadru- 
ped, lower in the series than has yet been observed. On the 5th of 
April last, in the examination of the strata in the gorge of the Sharp 
Mountain, near Pottsville, Pa., where the Schuylkill breaks through it, 
a large mass of remarkably fine old red sandstone attracted my atten- 
tion. Imprinted upon it, | was surprised to find six distinct impressions 
of foot-marks, in a double row of tracks, each mark being duplicated 
by the hind foot falling i into the impression of the fore foot, but a little 
more advanced. The strata here are tilted a little over the vertical, 
and the surface of rock exposed was about twelve feet by six, the 
whole of which surface was covered with ripple marks and the pits of 
rain bid aa Lmaemibis displayed in the very fine texture of the deep 
red sandst 
The six ecaeh impressions distinctly show, in the two parallel rows 
formed by the left feet on the one side and the right feet on the other, 
that the animal had five 
tues on the fore feet, 
three of which toes were 
unguinal endages. 
The length aie double 
my 
The mark of the drag- ae. : ~ 5. 
ging of the tail is dis- —~e&. SS a” wae 
tinct, and occasionally et 
slightly obliterates we 
AN 
‘ 
Nang 
aN 
Ae 
Ate 
marks. The ripple 
marksare seven toeight 4 
x 
in 
se 
Similate remarkab! 
those of the recent fas tc a and are diets some- 
what analogous to the Cheirotheriu 
The geological position of this copii pa Te is of great inter- 
est, from the fact that no such animal remains have heretofore been 
discovered so low in the series. Those deieiliad by Dr. King, in the 
great western coal field, are only eight hundred feet below the surface 
of the coal cena -(No. 13, of Prof. Rogers, the State Geologist.) 
* The figure is rather more than half the natural size of the impression. 
