C. Lyell on causal §e. 25 
pte HL —On the Boilenes of Fossil Pinte of a Pt She 
_ allied to the Cheirotherium, in the Coal Strata of Penns ylva- 
nia; by Cuarues Lye, Esq., F. R. S., FG. S., &e. 
(Communicated by the Author.) 
Ox my way from Pittsburg to Philadelphia, I visited the rocks 
in which Dr. King, of Greensburg, first discovered, in 1844, the 
footmarks supposed to have been made by a large reptile, and 
which stand out in relief from the lower surface of slabs of sand- 
stone, resting ona thin layer of fine clay. Having visited the 
quarry and enquired into all the circumstances of the discovery, 
having seen almost every specimen hitherto obtained, and con- 
sidered the relations of the sandstone with the rocks lying above 
and below it, I have no hesitation in declaring my conviction, 
first, that the footprints are genuine, and were made by a quad- 
ruped nearly alhed to the Cheirotherium of Europe, if not the 
same ; secondly, that they occur in the middle of the carbonifer- 
ous formation, having both above and below them seams of coal 
and strata containing Lepidodendron, FoF Stigmaria, Cala- 
_ mites, é&c. . 
Great praise is due to Dr. King for the exertions which he has 
made in bringing these fossils to light, and duly appreciating from 
the first their extraordinary importance and value. A young man, 
engaged in an extensive medical practice in a remote town, act- 
ing under every discouragement which want of sympathy. in 
those immediately around him, and of access to scientific books 
or museums could produce, he has persevered and succeeded in 
forming a fine collection of the fossil tracks, and become acquainted 
with the relations and organic remains of the contiguous strata.* 
I shall begin by describing the first locality to which the at- 
. tention of Dr. King wascalled in 1844, a stone quarry about five 
miles S. E. of Greensburg in Westmoreland county, Pennsylvania. 
The slabs of argillaceous sandstone are extracted here for paving, 
but the excavation begun in the bank of a small stream was soon 
desisted from in cqnnergsante of the increasing thickness of the 
* Three papers have somenta shie Seni from Dr. King. The first de- 
scribes and figures the footmarks from five miles S. E. of Giovtshoay, vol. xlviii, 
p. 343; the second, those of Derry, vol. xlix, P- 216; and lastly, the supposed 
hoofed:prints at Connelsville, second series, vol. 3, p. 268. 
Sxconp Serizs, Vol. IH, No. 4—July, 1846. 4 
