96 Prof. E. Hitchcock: on a new Fossil Fish. 
Art. XI.—On a new Fossil Fish, and new Fossil Footmarks ; 2 
by Prof. Epwarp Hircucocx, of Amherst College. 
1, History of the Discovery and general character of the Jaw | 
of anew Family of fossil fishes. oes 
Tuts specimen was presented to the American Association for 
the Advancement of Science, at its meeting in Providence in 
August, 1855. I received it from Rev. John Hawks, of Monte- 
me, by Dr. S. B. Bushnell of the same place. Mr. Hawks says, 
“it was found in Park County, Indiana, near the Wabash river, 
in a layer of slate, about one foot beneath the surface of fe 
ground. Immediately beneath the layer Pes slate, which 
about one foot in thickness, was a coal bank 
Having stated to the Association that this beautiful specimen 
was evidehttly the jaw of a shark, but of most peculiar structure, 
I had not the presumption to throw out my crude suggestions 
concerning it, when a gentleman present to whom the intricacies | 
of fossil ichthyology were as familiar as household words. I 
therefore requested Professor Agassiz to give his views of the : 
8 
) 
imen 
That gentleman expressed his conviction that the ime’ 
was the jaw of a new and extraordinary family of sharkes| allied 
to the sword fish, or Pristis. He stated that the sword of the 
Pristis was originally composed of more than one bone, which <4 
became united. If those bones were to be permanently separa- | 
tod and armed with teeth only on one side, they would resemble 
the fossil specimen, except that the latter is curved. Such an 
arrangement he supposed to have existed in the fish from which 
this jaw was taken: that is, it had two swords, armed on the 
outer side with sharp serrated teeth. The supposition seemed 
ee reasonable that it was received by the Association with er 
plause. 
Prof. Agassiz said that such an animal would not only form 
new genus of fossil fishes, but a new family. And he regard 
the discovery of as great importance almost, in fossil ichthyology, 
as was that of the Ichthyosanrus and Plesiosaurus in fossil Her- 
petology. The specimen will be committed to him for descrip- 
tion. But it seemed desirable, on several accounts, to give this 
brief history of its discovery, and a popular description of its 
characters. The whole of it is a good deal mineralized, being 
converted mostly into black limestone ; and from its weight, 
aaipert the presence of iron in some form. 
