353 Geological Survey of the State of Ohio. 



In the sandstone of the Connecticut valley, ichthyolites {Palceo- 

 thrissa inacrocephala) occur abundantly. Besides, according 

 to Professor Hitchcock, the bones of a vertebrated animal, sev- 

 eral feet in length, and not at all fossilized, have been found. In 

 addition to this, ornithichnites* are found, the occurrence of 

 which, while it draws line of demarkation between that forma- 

 tion, and the old red sandstone, must separate it from any forma- 

 tion in Ohio. For these reasons, we think that the new red sand- 

 stone of the Connecticut valley, cannot have an equivalent in 

 Ohio — that the two formations were produced at distinct geologi- 

 cal epochs, and under circumstances widely different.! 



One of the principal topics embraced in Dr. Hildreth's report, is 

 the range and extent, as well as the economical value of the buhr, 

 or, as he terms it, the calcareo-silicious deposit. " It is," he justly 

 remarks, " one of the most interesting features in the geology of 

 the coal measures of Ohio, and like the meridian line in geogra- 

 phy, will afford a valuable guide in developing the rock strata 

 which lie beneath, or are superimposed on this deposit." This is 

 a protean rock, at one time assuming a cellular aspect, with little 

 or no admixture of calcareous matter, and again passing into a 

 compact cherty limestone. Yet we are assured, (p. 29,) that 

 under every aspect it may be known by the imbedded fossils which 

 accompany this rock in its whole course. The fossils, he after- 

 wards informs us, peculiar to this deposit, are Encrini, Producti, 

 Spiriferi, Terebratulas, &c. Here we remark, that particular fos- 

 sils are characteristic of particular formations ; but we have not 

 sufficient evidence to believe that the particular members of a 

 group have their peculiar fossils. We have noticed all the fossils 

 enumerated, in the mountain or carboniferous limestone, which 

 underlies the coal measures of Ohio, in many of the iron ores in- 

 terstratified with them, in the blue limestone below the buhr, in 

 the limestone in contact with it, and some of the fossiliferous 



* Some few individuals have atteriipted to throw discredit on these discoveries of 

 Professor Hitchcock; but, for ourselves, we regard the existence of ornithichnites 

 as clearly settled as that of the orthoceratite or productus. An inspection of the 

 Professor's specimens we think, must convince the most incredulous. While we 

 regard it as one of the most interesting discoveries which has recently been made 

 in geology, we deprecate every attempt captiously, and without the examination 

 of the evidence, to detract from the well earned reputation of the author. 



t The writer has not informed us to what place he would refer this sand- 

 stone. — Eds. 



