134: Kindle — Unconformity at the Base of the 



least of the fishes credited to the Huron shale by Newberry 

 and unknown in the Cleveland, came, not from the Huron, 

 but from the Olentangy shale at the base of the Huron. This 

 conclusion is evident from the remarks concerning Callogna- 

 thus regularis on page 60 of Newberry's monograph* although 

 it is referred under the description of the species to the Huron 

 shale. With increasing knowledge of the fish fauna of the 

 Huron we may confidently expect the discovery of a consider- 

 able number of species common to both the Huron and the 

 Cleveland shales. The general resemblance of the conodont 

 faunas of the two formations seems fully to justify this pre- 

 sumption. The writer's collection from the Huron shale will, 

 when studied, it is believed, add other species of fishes to those 

 which are known to be common to the Huron and Cleveland 

 shales. 



Professor Newberry, in his latest reference to the conodonts 

 of the Cleveland shale, dismissed the evidence which these fos- 

 sils might have yielded him with the statement that " the mil- 

 lions of conodonts in it have no geological significance. "f This 

 view is evidently not shared by Dr. Bassler, who has based his 

 correlation of the Chattanooga shale of Tennessee and the 

 Cleveland shale of Ohio entirely on the similarity of the 

 conodont faunas in the two. Nor is it shared by the writer, 

 although, as previously stated, detailed discussion of the evi- 

 dence which this group will afford must wait the description 

 of the conodont faunas recently discovered by the writer in 

 the Huron shale in northern Ohio. A preliminary examina- 

 tion of the conodont fauna of the Huron shale shows that it is 

 very similar to that of the Cleveland shale. The most impor- 

 tant facts now available, as bearing directly on the question of 

 the age of the Cleveland shale, relate to the known range 

 outside of Ohio of the species which have been recognized in 

 it. Only three of the Cleveland shale species of conodonts 

 have thus far been recorded from other formations. These 

 are Prionides angidatus Hinde, Prionides erraticus Hinde, 

 and Polignathus dubius Hinde. These species are recorded 

 only from Hamilton and Genesee horizons^ elsewhere, so that 



*Mon. U. S. Geol. Survey, No. 16, 1889. 



•f Mon. U. S. Geol. Survey, xvi, page 128, 1889. 



X Hinde, George H., On Conodonts from the Chazy and Cincinnati Group 

 of the Cambro-Silurian, and from the Hamilton and Genesee-shale Divisions 

 of the Devonian, in Canada and the United States. Quart. Jour. Geol. Soc, 

 London, vol. xxxv, pp. 351-368, 1879. 



Clarke, J. M., Annelid Teeth from the lower portion of the Hamilton 

 Group and from the Naples Shales of Ontario Co., N. Y. N. Y. State Geol., 

 Sixth Ann. Eep. for 1886, pp. 30-33, pi. Al. 



Grabau, A. W., The Palaeontology of Eighteen Mile Creek and the Lake 

 Shore Sections of Erie Countv, New York. Bull. Buffalo Soc. Nat. Sci., 

 vol. vi, pp. 150-158, figs. 33A-33I, 34-46, 1899. 



