22 BULLETIN OF THE LABORATORIES 



decided carboniferous habitus. At Rusville the following section is 

 exposed : 



Shale, with Productus semireticulatus and 



Spirifcr striatifoimis loo ft. above congl. II. 



Shales and thin bands of freestone 30 ft. 



(Pleurotomaria, etc.) 



Nodules of lime (fossiliferous) 61^ ft. above congl. II. 



Shales. 



Freestone, 40 feet above congl. II. Nau- 

 tilus sp., Hemipronites, Productus 

 arcuatus, eic about to ft. 



Shales . about 30 ft. 



Conglomerate and sandy freestone 5 ft. 



" Conglomerate II '" forms the basal, iS inches or so, and here is not very 



coarse. 

 Shale>^, with Allorisma vvinchelli, Prothyris meeki, Sanguinolites obliquus, 

 Grammysia ventricosa. and Pholadella newberryi. 



'Ihis last is the lowest horizon seen in this part of the state and cor- 

 responds to the shales overlying the freestone in Licking county. 

 The fauna found at the highest horizon of Waverly in Licking county, 

 is here encountered here near the top and the various species can be al- 

 lotted to their position in the series with unexpected ease and cer- 

 tainty. 



The little excursion thus made into Muskingum and Perry coun- 

 ties enables us to complete the series in its normal condition. How- 

 ever, the moment we turn our attention to our allotted task in Licking 

 county, we discover that the series is imperfect at one point. While 

 conformity between the upper Waveriy and lower Chester does not 

 exclude the idea of a considerable interval of time between the fossil- 

 iferous bands of the two groups, it is apparent that in Licking county 

 the Chester interval is unre-presented and that much of the upper Wa- 

 verly is generally absent, so that the white sandstone or conglomerate 

 of the coal-measures lies unconformably on one or other of the Waverly 

 beds and the upper surface of the Waverly itself has obviously suffered 

 erosion. The amount of the erosion varied in different places and where 

 greatest is covered by coarse quartz pebbles of granitic origin mingled 

 with coal measure trees of large size. The suggestion of extensive erosion 

 been heretofore made, but absolute proof has been wanting. It is has 

 our privilege to complete the evidence and to point out in general the 

 amount of loss thus incurred. It has been quite generally supposed 



