196 GEOLOGY OF OHIO. 



the State, where only one of the members is well developed, has occa- 

 sioned much confusion. The strange assumption that the entire series. 

 of over 500 feet is essentially homogeneous paleontologically has mili- 

 tated against a correct appreciation of the nature of the problem. This 

 may be in part explained as a result of the great monoton}^ of the litho- 

 logical characters of the series and is, in part, an illustration of the doni- 

 inancy of a name. So long as collectors remained satisfied with labeling 

 specimens "from the Waverfy group of Ohio" (as adequate a datum as 

 "from the Upper Silurian of New York" would be), it is little wonder 

 that the formation was found irreconcilable to any scheme of classifi" 

 cation. 



Furthermore, the fact that the strata are almost exclusively littoral 

 and that their position is frequently complicated by sand-bar and fluviatile 

 agencies explains many perplexing complications. In the present paper 

 it will be impossible to enter into detail; in the paleontological portions 

 especially it must be admitted that a final clearing up of the synonomy 

 cannot be undertaken until the numerous species more or less fully de~ 

 scribed by the lamented Alexander Winchell shall have been reviewed 

 and illustrated. This work, which the distinguished Michigan geologist 

 left unfinished when so unexpectedly called hence, remains an impera- 

 tive need of American geolog3^. It should also be remembered that the 

 writer makes no pretense at being a professional paleontologist and only 

 ventured to describe the material collected when it was possible to ac- 

 compan}' the description by a figure which would serve to enable others 

 to use the data on which his conclusions were drawn. After some 3- ears 

 of complete neglect of this subject, to which he never expects to return, 

 it would be useless to attempt a revision of the descriptions already as 

 fully elaborated as the opportunities permitted. The accompanying il- 

 lustrations will enable the reader to determine at a glance the salient 

 characters of the several horizons. Mistakes of various sorts made dur- 

 ing these studies and incident to the method of publication have been 

 corrected as far as possible, while those which remain are recommended 

 to mere}". It remains to acknowledge the assistance afforded me in this 

 study by my revered friend, Professor Edward Orton, to whom Ohio and 

 the science of Geology, in common with hundreds of students who have 

 sat under his personal instruction during more than a score of years, are 

 deeply indebted. 



Historical. 



It will be unnecessary to attempt a complete resume of the history of 

 opinion because Professor Alexander Winchell has given a very elaborate 

 discussion of the subject in the Proceedings of the American Philosoph- 

 ical Society, vol. XI, 1869. The earliest reference to the rocks here in 

 discussion is a paper by Dr. S. P. Hildreth in the American Journal, Vol- 

 29, upon the "Bituminous Coal Deposits of the Valley of the Ohio." 



