220 • Cincinnati Society of Natural History. 



It is still doubtful to what period the formations belong. 

 The yellow clay is unquestionably of post-glacial origin, while 

 the bowlder-clay (Hard Pan) is as certainly glacial. They 

 both contained small fragments of carbonized wood and rare 

 traces of vegetable matter. The yellow clay, which was 

 rather uniform, extended to a depth of five feet eight inches, 

 where it graduated somewhat unevenly into the blue clay, 

 which had an average depth of seven feet three inches. The 

 blue clay passed gradually from a smooth even consistency 

 above, through all the intermediate stages, to a decidedly 

 gravelly condition below. Sand was found at different depths 

 and of different kinds, in each instance being a clearly marked 

 pocket of greater or less extent. Yellow sand was only found 

 in the north-west corner of the second shaft and in one large 

 pocket. The bones that were in contact with it were very 

 badly decayed. The other sand pockets contained a rather 

 uniform fresh-water sand. In two instances, however, the 

 sand contained numerous minute shells with a quantity of 

 fragments.* In these cases the surrounding clay, particularly 

 that above, contained similar mollusks. 



The peculiarity of the horizon w r as so perplexing that Dr. 

 Edward Orton was requested to visit the diggings and assist 

 in reaching some decision. 



This decision hinged entirely upon the relation of the blue 

 clay to the remains. If all or even a good portion of the clay 

 had been above the bones, they naturally would have been 

 termed inter- or even preglacial. But as it is, it is a much 

 more difficult problem. The bones reached to the bottom of, 

 and, at least once, below 7 the bowlder-clay; while the latter 

 did not entirely cover them, for a few small fragments w 7 ere 

 found in the yellow clay, and, in one instance, a tusk, which 

 at its base rested at the bottom of the blue clay, pierced the 

 latter and penetrated the overlying yellow clay for a short 

 distance with its tip. 



It seems as if the Hard Pan was either deposited after or 

 during the heaping up of the bones from the neighboring 

 swamp. The evidence being somewhat questionable and con- 

 trary to all former discoveries of mastodon and mammoth 



*Physa aricillaria, Say ; Planorbis Gyraulus parvus, Say ; and Anculosa cos- 

 tata, Anth. were present in abundance, but of a small size. 



