512 GEOLOGY OF OHIO, 



Devonian habitus of the Cuyahoga and not for any strict chronological 

 parallelism. 



The upper fifty feet of the Cuyahoga shale in central Ohio (that por- 

 tion previously called "Waverly shale" 1 ) has a remarkable and very dis- 

 tinct fauna. This has apparently not been fully studied by any previous 

 observer. The typical exposures are between Granville and Newark and 

 a few other localities in Licking county. The same fossils are found near 

 Loudonville, at Gann, at the water's edge below the dam at Ports- 

 mouth, etc. ; in all these cases these fossils are within a few feet of con- 

 glomerate I. Most of the species are limited to the horizon, not extend- 

 ing more than thirty feet below this conglomerate, which may be sought 

 below the freestone everywhere quarried in picking and adjacent 

 counties. It is a noteworthy fact that this stratum contains a very large 

 portion of the Waverly species which have also been described in Michi- 

 gan. Ctenodonta iowensis, Edmondia burlingtonensis, Grammysia fam- 

 elica, Nuculana spatulata, N. similfs, Orthonota rectidorsalis, Palceoneih 

 elliptica, P. plicatella, P. elegantula, P. marshallensis ; P. allorismiformis, 

 P. attennata, Sanguinolites unioniformis , S. senilis, S. naiadiformis, 

 Schizodus prolongatus, Streblopteria squama, S. media, Betlerophon cyrto- 

 lites, B. galericulatus, Orthoceras rushensis, and many others give an 

 unmistakable habitus to the assemblage. Many of these or allied forms 

 occur in the Kinderhook and Marshall groups and quite a number are 

 found above the conglomerate in the freestone of the middle Waverly. 



Division II — Kinderhook Group — Waverly Freestone — Lower 

 Part of the Logan Group — Waverly Conglomerate. 



This period was one of greater activity and slight fluctuations in 

 level. The distance between the two conglomerates is only about 60 feet 

 in a normal section and the conglomerates vary from a few inches to sev- 

 eral feet. The writer has attempted to show that many of the difficulties 

 in the way of a clear understanding of the middle Waverly arise from the 

 local eccentricities of these conglomerates. That there are two such 

 bands seems not to have been suspected. Both are subject to great local 

 variations. They may take the place of the whole series. On the other 

 hand, they may be absent or only represented by a few pebbles of quartz. 

 Fortunately both are indicated by the remarkably persistent associated 

 fauna. That of the lower conglomerate has been recognized near the 

 top at Weymouth. 



A number of 'fossils are characteristic if not exclusively restricted to 

 the freestone of this division, viz: Proetus auriculatus, Allorisma 

 nobilis, A. cooperi, Dexiobia ovata, Crenipecten winchelli, Leiopteria ortoni, 

 Microdon reservatus, Modiola waver lensis, Modiqmorpka hyalea, Myalina 

 michiganensis, Oracaraia cornuta, Pholadella newberryi, Sanguinolites 



•The Cuyahoga shale and the Waverly problem. Bui. Geol. Soc. America, vol. 

 II, p. 37, Jan., 1891. 



