126 CONTRIBUTIONS 



Observations. Smaller than the above, this species has 

 some resemblance to it. It differs in being a flatter shell, 

 in being highly polished, and in having the outer lip thick 

 ened where it is in contact with the whorl. Immediately 

 below the umbilicus there is usually a slight impression on 

 the- lip. 



T. lineata. Plate 4. Fig. 116. 



Description. Shell rather depressed above, rounded be 

 low, nearly covered with transverse elevated lines, smooth 

 round the umbilicus ; substance of the shell thin ; suture 

 furrowed; umbilicus rather large, round; whorls four; 

 mouth round ; outer lip edged. 

 Length .1, Breadth 3-20ths, of an inch. 



The smaller figure is of the size of nature. 



Observations. This minute species differs from the pre 

 ceding, in having transverse lines and a wide furrow 

 along the suture. The whorls are also more rounded. 



The genus Turbo has been observed in Great Britain, 

 as low down as the Mountain Limestone, and through 

 nearly all the superincumbent strata to the Crag. Eigh 

 teen species are mentioned by Sowerby, Phillips and Bran- 

 der, two only being in the London Clay. M. Deshayes s 

 Tables give thirty-four for the Tertiary, sixteen being in 

 the Eocene of the Paris basin alone. In this country 

 there have not been before, that I am aware of, any of the 

 Turboncs noticed in our formations. 



