CERITIIIUM. 159 



anterior portions of the whorls. Spirals on the base of the body-whorl scarcely 

 granulated. Other indications wanting. 



Relations and Distribution. — 0. LecJcenbyl may, perhaps, be regarded as an 

 unusually fine development of G. Beanii, from which, however, it differs in its 

 greater size, more marked turriting, and in the details of its ornaments. Rare in 

 the Dogger. 



80. Ceuithium Beanii, Morris and Li/cett, 1851. Plate IX, figs. 5 a, 5 6. 



1851. Ceeithium Beanii, Jf. and L. Great Ool. Moll., p. 112, pi. xv, fig. 5. 

 1884. — — — Hudleston, Geol. Mag., dec. iii, vol. i, 



p. 59, pi. iii, figs. 10 and 11. 

 Compare also for varieties 

 Ceeithium PUPiEFOBME, Koch and Dunker. Beitr., p. 33, pi. ii, fig. 10. 



Bibliography, 8fc. — Although described by the authors of the ' Great Oolite 

 Mollusca ' as occurring near Scarborough, their type, I have very little doubt, 

 came from the Dogger at Blue Wyke. 



Description of the Dogger or type-form : 



Length varying from . . 9 — 12 mm. 



Width ..... 3—3-5. 

 Spiral angle of apex . . . 25°. 



Do., anterior portion of spire . .15°. 



The above dimensions are only approximate, regard being had to the 

 numerous varieties. 



Shell small, more or less pupoid, turrited ; whorls from ten to twelve, 

 narrow, and rather flattened. The anterior whorls are ornamented by five 

 tuberculated spirals, of which the third and fifth are least prominent. Sometimes 

 the tubercles become slightly confluent, in which case there is a tendency to the 

 formation of axial costse, especially in the upper part of each whorl. The upper 

 row of spirals is strongly tuberculated, though this feature is subject to some 

 variety. 



Body-whorl slightly compressed, and not exceeding one-third the total length 

 of the shell ; ornaments as in the anterior whorls of the spire. Base spirally 

 striated. Aperture subquadrate ; columella short, and terminated by a short 

 but rather deeply cut anterior canal. 



Relations and Distributio7i. — The Yorkshire specimens are to a certain extent 

 sui generis. Those from the Lincolnshire Limestone, and the very rare specimens 

 from the Inferior Oolite of the Cotteswolds, vary considerably from these types. 



