LYELL ON THE EOCENE BEDS OP NORTH AMERICA. 



439 



Natica ostites 



Turritella 



Bulla, same as one from Shell Bluff 



Trochus agglutinans 



Infundibulum trochiforme 



Solarium canaliculatum 



Dentalium 



Crassatella 



Lucina pandata 



Cytherea 



Cardium, like one from Shell Bluff 



Chama, like one from Shell Bluff 



Cardita 



Lithodomus dactylics 



Modiola 



Mytilus 



Avicula trigona ? 



Pecten 



Ostrea panda 



c. Melania, cast. 



Cerithium Georgianum. 

 a. Nucleus. b. Cast of exterior. 



The shell named Cerithium Georgianum in the above list (figs. 

 #, b.\ is very abundant, and closely resembles C. lamellosum 

 Lam., a tertiary species of the Paris basin. Its characters are as 

 follows : — 



Cerithium, with an acuminated turreted shell, volutions 9 or 10, rounded, with 

 rather obsolete and irregular longitudinal ribs, and with 5 or 6 transverse ridges, 

 of which the three anterior are very prominent, and lamellose near the aperture. 



Of the next shell in the list, named Melania (fig. c), there is 

 only a cast of the inside preserved, so that its external characters 

 cannot be distinctly known. 



Of the Lithodomus dactylus I obtained a beautiful cast, both 

 of the exterior and interior, from the cavity of a fossil coral. It 

 resembles the West Indian variety, and is an eocene species 

 well known in the Paris basin. As, according to Philippi, it is 

 one of the most cosmopolitic of living species, we have the less 

 reason to be surprised at its great vertical range in the geological 

 series.] 



A species of Scutella differing from those found by me in other 

 places was common at Jacksonboro'. For the following descrip- 

 tion of it I am indebted to Professor E. Forbes, and it has been 

 named, after Colonel Jones of Millhaven, Scutella Jonesii : — 



