Some new Upper Greensand Gasteropods. 283 



to distinguish between them. The chief differences are, that 

 the angle is placed much higher up on the body-whorl, that 

 there is an obscure keel below it, that the columellar lip is 

 enormously thickened, and the aperture in consequence nar- 

 rowed, and, finally, the labial tooth. This and the following are, 

 I believe, the first tuberculated species which have been ob- 

 served. 



Rare. Coll. J. Carter, Esq. 



Pterodonta longispira. PI. XL fig. 3. 



Shell elongated, spirally striated. Spire formed of six or seven 

 whorls, which are twice as wide as high, round, and ornamented 

 with about ten longitudinally elongated tubercles. Body-whorl 

 of moderate size, with a sharp angular keel on the upper part, 

 and on the lower part a wide elevated obtuse keel or inflation ; 

 between these the shell is very concave ; and near the mouth, 

 on this intermediate space, is placed the transversely oval 

 tooth ; this space is considerably wider than that above, 

 which is flat and oblique. Columellar lip moderately thick- 

 ened. Mouth elongated, rather narrow. 



This species is easily distinguished from every other by its 

 keel and the inflated ridge of the body-whorl. It almost as 

 closely resembles Rostellaria Orbignyana (P. & R.) as the pre- 

 ceding shell does R. marginata. The principal distinctions are 

 the keels not nodulated, the columellar lip thickened, and 

 the labial tooth. The spire also is more elongated than in 

 English specimens of R. Orbignyana. 



Not common. Coll. J, Carter, Esq. ; University. 



Pyrula [Myristica) Sower bii. 

 Inflated, ovately fusiform, striated ; spire one-third the length of 

 the shell. Whorls rounded, with two obtuse angles, between 

 which is the line of suture ; crossed on the most tumid part 

 with numerous longitudinal ridges. Mouth half as wide as 

 high. 



This is the Pyrula Smithii, described by J. Sowerby in Dr. 

 Fitton^s paper (Trans. Geol. Soc. 2 ser. vol. iv. t. 11. fig. 15 b). 

 That name having been previously applied to another species, I 

 have proposed for it one commemorative of its describer. 



Very rare. Coll. University ; Mr, W. Farren. 



Fusm tricostatus. PL XI. fig. 4. 

 Ovately fusiform ; composed of few whorls, apparently four. 

 Spire about one-fourth the length of the shell, exclusive of the 



19* 



