GASTEROPODA. 113 



Shell thin, globosely conical, subtrochiform, or rather turbinated ; spire slightly 

 elevated ; whorls 4 — 5, convex, rounded ; suture deep ; aperture circular ; peritreme 

 sharp, continuous ; umbilicus moderate, deep. 



Elevation, \ of an inch ; diameter of base, the same. 



Locality. Mam. Crag, Bramerton. Recent, Britain. 



This shell I believe to be rare ; two specimens of it were given to me by 

 Mr. Lyell, and a few others sent for description by Mr. Wigham are all that I have 

 seen. This species has also been found plentifully in the Fluviatile deposits of 

 Grays, Clacton, and Stutton ; and from the former locality a shell was described by 

 Mr. Morris and Mr. Sowerby, under the name of antiqua, which was larger, more 

 elevated, and with less convex or rounded volutions ; and it was considered by 

 those gentlemen a distinct species. Specimens have been since found possessing 

 an intermediate character, some of which are in my own cabinet ; and it is now 

 generally considered by most conchologists only as a variety. 



Vermetus,* Adanson, 1757. 

 Serpulorbis. Sassi. 



Gen Char. Shell elongate cylindrical, tubular, spiral in its young state, after- 

 wards twisted without regularity ; aperture small and circular, adherent generally 

 by the apex or upper volutions ; operculum corneous, circular, and multispiral. 



This approaches so near to the testaceous Annelides, that it cannot be 

 distinguished by the shell alone. By the examination of the animal, malacologists 

 have, however, determined it to be a true Mollusc, approaching, in many of its 

 characters, to the genus Turbo. 



1. Vermetus intortus. Lam. Tab. XII, fig. 8, a — b. 

 Serpula intorta. Lam. 

 Vermetus intortus. Brown. Lethea Geogn. p. 990, Taf. 36, fig. 18, a, b, c, 1837. 



— S. Wood. Catalogue 1842. 



— Phil. En. Mol. Sic. vol. ii, p. 144, 1844. 

 Dale. Hist, and Antiquities of Harwich, t. 13, fig. 1, 1730. 



V. Testa plerumque gregarid, tereti, subquadratd, arete spiratd, fere tola qffixd, repente ; 

 striis transversis undulato-rugosis ; lineis tribus longitudinaliter instructis, extremitate 

 anticd aliquando libera, porrectd. 



Shell generally gregarious, tubular, subquadrate, literally affixed for a con- 

 siderable length, closely and regularly spiral in the young state, transversely 



* Etym. Vermis, a worm. 



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