Utriculus. 



MOLLUSCA. 



iOl 



5. Bulla attendata. — The Attenuated Bulla, pi. XLVII. 

 fig. 24. 



Bulla attenuata. Sowerby, V. p. 97, pi. 464, fig. 3. Fle- 

 ming, p. 295. 



Elliptical, narrow above, ventricose in the middle, with an 

 expanded, well rounded base ; aperture long, curved, narrow 

 above, expanded below ; outer lip extending beyond the top of 

 the body, which is truncated above, with a deep perforation ; 

 surface covered with fine, transverse stria;, which are narrower 

 and less conspicuous in the middle, and close set and deep 

 above, more numerous below, but rather indistinct. About 

 twice as long as wide. 



London Clay at Hordwell. 



6. Bulla acuminata The Acuminated Bulla, pi. 



XLVII. fig. 15, 16. 



Bulla acuminata. Sowerby, V. p. 98, pi. 464, fig. 5. 



Elongated, cylindrical ; vertex acuminated ; aperture linear, 

 narrow, a little wider at the base ; outer lip rising a little above 

 the vertex, and produced to a point ; surface with fine, regular, 

 transverse striae, which are somewhat obscure in the middle. 

 Length equal to thrice its diameter. 



London Clay, Barton Cliff. 



7. Bulla constricta The Constricted Bulla, pi. 



XLVn. fig. 17, 18. 



Bulla constricta. Sowerby, V. p. 96, pi. 464, fig. 2. 



Subcylindrical, with a central constriction ; vertex truncated, 

 and deeply perforated ; aperture linear, contracted above, and 

 considerably widened below ; base rounded ; superior portions 

 of the exterior smooth; base with obscure, spiral striae. Length 

 three times its diameter. 



London Clay at Barton Cliff. 



8. Bulla Mantelliana — Mantell's Bulla, pi. XXXIII.* 

 fig. 31. 



Bulla Mantelliana. Sowerby, Geo. Trans. IV. 2nd series, 

 p. 346, pi. 22, fig. 3. Mantell, Geo. S.E. of England, p. 249. 



Cylindrical, smooth ; truncated at both extremities, but not 

 umbilicated ; aperture contracted above, and considerably 

 widened below ; outer lip a little inflected in the centre. 

 Length nearly double its diameter. 



Hastings Sand, Tilgate Forest. 



Genus IL—UTRICULUS.— 5/-o?f;K. 



Shell small, oblong-ovate; body very large; spire very 

 short, with rounded volutions ; aperture frequently as 

 long as the body, and others not, narrow above, wide, 

 and rounded at the base; lips continuous; outer lip thin, 

 and slightly inflected ; inner lip not reflected on the 

 columella. 



SECTION I aperture NOT SO LONG AS THE BODY. 



1. Utriculus humekalis The Shouldered Utriculus, 



pi. XLVII. fig. 26. 



ActcEon humeralis. Phillips, I. p. 129, pi. 11, fig. 34. 



Subcylindrical, smooth ; body long, a flat space on its superior 

 margin ; spire short, consisting of four subturreted volutions, 

 flattened above, and ending in an acute apex; apex oblong-oval, 

 a little compressed above, and rounded below ; outer lip with a 



slight flexure near its centre; inner lip narrowly reflected on 

 columella. 



Blue Wick of the Inferior Oolite. 



2. Utriculus crenatus. — The Crenated Utriculus, pi. 

 XLVn. fig. 21, 22, 23. 



Acteon crenatus. Sowerby, V. p. 87, pi. 460, fig. 1. Tor- 

 natella crenetics, Fleming, p. 336. 



Oblong-ovate ; body large, a little ventricose ; spire small, 

 acute, with four very slightly inflated volutions, and a shallow 

 sutural line ; aperture elongated, narrow, about two-thirds the 

 length of the body, contracted and pointed above, gradually 

 widening below, and terminating in a rounded base ; outer lip 

 sharp, almost straight ; columefla with a series of minute cre- 

 nulations. Fig. 23 is the natural size of the shell. 



London Clay, Barton Cliff. 



3. Utriculus elongatus — The Elongated Utriculus, pi. 

 XLVII. fig. 27, 28, 29. 



Actceon elongatxis. Sowerby, V. p. 88, pi. 460, fig. 3. Tor- 

 natella elongatus, Fleming, p. 337. 



Greatly elongated, subcylindrical; body long; spire of me- 

 dium length, with four gradually tapering volutions, defined by 

 a narrow sutural line, and ending in an obtuse apex ; aperture 

 short, about half the length of the body, slightly oblique, con- 

 tracted above, and rounded and widened beneath ; outer lip a 

 little expanded, and slightly inflected in the centre ; whole sur- 

 face covered with very fine spiral stria, which are very indistinct 

 on the spire and superior portion of the body. Fig. 28 is the 

 natural size of the shell. 



London Clay, Barton Cliff. 



section II — aperture as long as the body. 



4. Utriculus glaber The Smooth Utriculus, pi. 



XLVIL fig. 30. 



Utriculus glaber. Brown, Elts. Foss. Conch, p. 64, pi. 5, 

 fig. 9. Actceon glaber, Phillips, Geo. of Yorkshire, I. p. 129, 

 pi. 9, fig. 31. 



Cylindrical, oblong ; body very large ; spire very short, 

 depressed, consisting of three slightly inflated, gradually dimi- 

 nishing volutions, the apicial one obtuse ; aperture elongated, 

 narrow, extending the whole length of the body, straitened 

 above, gradually expanding as it descends, and pretty wide 

 below ; outer lip nearly straight ; columellar lip destitute of a 

 thickening ; whole surface smooth, with wide-set, indistinct, 

 nearly equidistant, transverse striae; base rounded. 



Grey Limestone of the Cave Oolite at Cloughton. 



FAMILY IL_CALYPTRACEA. 



The branchise of the animal situated in a dorsal cavity, 

 or projecting beyond its shell, which is invariably exte- 

 rior. 



Genus IIL— ANCYLUS.— Mw/Zer. 



Shell thin, obliquely conical, patelliform ; vertex some- 

 what pointed, short, turned backwards, and slightly 

 inwards, but not spiral ; aperture oval, or oblong, with 

 the margins simple and entire. 

 2c 



