410 GASTEROPODA OF THE INFERIOR OOLITE. 



Description : 



Height . . . . .13 mm. 



Basal diameter . . . .18 mm. 



Spiral angle . ... . . 84°. 



A single specimen from Crewkerne station (? Parkins om-zone) corresponds well 

 with the description in the " Terrains Jurassiques." The spire is very convex, 

 and the ornaments similar. The peculiarity of the sinus-band, which is wide and 

 placed in a groove towards the middle of the whorls, further helps the 

 identification. In d'Orbigny's figure the base is somewhat fuller than in my 

 specimen, and the aperture more oblique. 



347. Pleurotomaria, species or variety. Plate XXXV, figs. 5 and 5 a. 



Description : 



Height . . . . .18 mm. 



Basal diameter . . . .20 mm. 



Spiral angle ..... 66°. 



Shell conical, not umbilicate. Spire regular, with apex slightly obtuse. 

 Whorls (about seven) flat or scarcely convex, with close sutures, spirally striated, 

 and with conspicuous radial ornamentation in the posterior areas. There is a 

 small granulated belt at the base of each whorl. 



The sinus-band is anterior, and situated in a slight groove. In the body- 

 whorl, which is relatively large, the basal belt at the periphery become very 

 conspicuous ; base inclined to be flat, spirally striated and radially decussated, 

 rising towards the columella. There is no umbilicus whatever. Aperture 

 rhomboidal inclining to square, wi^h a nearly straight inner lip. 



Hitherto I have failed to identify this form, which differs from all the small 

 conical species previously described in the anterior position of the sinus-band. A 

 single specimen, believed to come from the Parhinsoni-zone of Burton Bradstock. 



348. Pledrotomaria (Leptomaria) sulcata, Sowerby, 1818. Plate XXXV, figs. 6, 



6 a, 6 b ; and obconical variety 

 figs. 7, 7 a, 7 b. 



1818. Titocntrs sulcatus, Sowerby (Miller's MS.). Min. Conch., pi. ccxx, fig. 3. 

 1854. Pleurotomaria sulcata, Sowerby. Morris, Cat., p. 272. 

 is":}. — — — Tawney, Dundry Gasteropoda, p. 43 



(35). 



