546 PAL.&0NTOLOGICAL REPORT OF GEOLOGICAL SURVEY. 



and not so easily separated into slabs. The remains of shells are gen- 

 erally much more numerous, and the number of species much greater. 

 This bed can generally be recognized by its parting. But it should 

 be observed that when the vein thickens much the clay partings are 

 double, and when it thins to two or three feet, there is, ordinarily, none; 

 but this last 1 case is very rare. 



Curlew mine, Union county, Kentucky. At this place, about one hun- 

 dred feetaboVe the main coal, wehad the first good opportunity of study- 

 ing the coal No. 11, and of collecting the fossil shells of its shales. 

 All the characters above described are found there. The coal at Cur- 

 lew, as of Shawneeton Company, Illinois,- is mostly bird-eye. In 

 the anthracite coal-fields of Pennsylvania, there is also a peculiar bed, 

 in which this kind of coal is generally seen. It would be very inter- 

 esting to ascertain if both these beds are on the same geological level. 

 This I was unable to do, since I saw only specimens of the coal in 

 cabinets, but never the place where they had been taken. 



At the Curlew mine, above the shales of No. 11, there is a bed of 

 fossiliferous limestone. 



Thompson's mine, Union county, Kentucky. Coal No. 11, is open at 

 this place. It is six feet thick, has a clay parting, and the shales 

 contain the remains of fishes, and some of the above mentioned shells. 

 There is above it a bed of limestone, passing into brown ferruginous, 

 hardened clay, fall of fossil shells of the same species as in the lime- 

 stone. 



Llewellyn mines, Union county, Kentucky. Same coal at this place, 

 about six feet thick, with clay parting, and limestone above the shales. 

 The shales, though thin, have the same fossil remains as the for ner. 



Providence, Hopkins comity, Kentucky. At this place the coal No. 

 11, crops out around the hill, on which the town is built. Its charac- 

 teristics are exactly the same as at Thompson and Llewellyn, viz : 

 coal five to six feet thick, with clay parting, covered with black slabby 

 shales, with remains of fishes, and some shells, and above them the 

 limestone, passing into rotten ferruginous brown stone or shale, full of 

 fossil shells, especially of a Prodactus Boyersi, marked with short 

 spines. About one mile west of the town, among the hills, there has 

 been opened a bed of coal, four to six feet thick, which has the same 

 shales, but wants the limestone above them. Nevertheless, the place 



