PAL.EONTOLOGICAL REPORT OF GEOLOGICAL SURVEY. 563 



half of the last whorl, and have not been found to exceed twenty -five; 

 whereas L. De Koninck reports on the B. Urei, from thirty-six to 

 thirty-eight. Dimensions — Diameter .~ T of an inch ; proportional 

 increase of the last whorl . T 4 -J T to .—„■ of an inch ; including the wings 

 of the mouth ; transverse diameter of the mouth . T Vo °f an inch. 



Remains of fishes, that have not yet been determined, are also 

 found in the shales of this coal. 



COAL NO. 11. 

 This is the next coal in the series, in which we found the remains of 

 mollusca,. For the most characteristic, see plate vin., figs. 1 to 11, 

 and plate ix, fig. 1. They are as follows : Pecten Providencesis, 

 Loxonema regularis, Chimnitgia parva, Pleurotomaria Bonharlorensis, 

 P. depressa, Area carbonaria, Gervillia longispina, Plicatula striato* 

 costata, Myalina pernaformis, Cardinia (?) fragilis, Macrocheilus, 

 gracilis, Orfhis resupinoides, Pedm, species undetermined, Avicula 

 rectalateraria, (not so abundant as in No. 9,) Loxonema Hallii, Loxo- 

 nema, species undetermined, Macrocheilus whabilis, Macrocheilus, spe- 

 cies undetermined, Productus muricatus, rare, P. Bogersii, P equicos- 

 tatus, Athyris subtilita, large and abundant, Cardium, species undeter- 

 mined, Spirifer Meusebachanus, Solenimya, species undetermined, Nu- 

 cula, species undetermined, Orthis, species undetermined, Orthoceratite, 

 species undetermined, Griffithides, species undetermined. 



This coal is usually separated into two members, by a clay parting 

 from one to four inches in thickness, and is overlayed by a limestone. 

 The upper part of this bed of coal is sometimes cannel, and the lower 

 bituminous. It is best developed in Hopkins county — where it at- 

 tains a thickness of nine feet — on the line of the Henderson and 

 Nashville Railroad. 



On the mining property of Edward and William Hawes, at Hawes- 

 ville, Hancock county, No. 11 is found near the top of the hill, a few 

 rods west of their entry into the main Hawesville coal, No. 1, B ; well 

 characterised by its peculiar fossils, and proves a remarkable thinning 

 out of the measures near the eastern boundary of the basin. The ver- 

 tical space between the two is here only two hundred and ten (210) 

 feet, but may be somewhat increased, by the existence of an at pres- 

 ent unknown fault. 



