GASTEROPODA. 169 



Ord. TECTIBBANCIIIATA. 

 Action,* Montf. 1810. 



Voluta (spec). Linn. 

 Solidula. Fischer. 

 Tornatella. Lam. 1816. 



Gen. Char. Shell ovate, convolute, subcylindrical, with a more or less elevated 

 spire ; striated or sulcated in a transverse or spiral direction ; aperture linear, narrow- 

 above, rounded below ; outer lip plain, generally sharp ; columella spiral, with tooth- 

 like projection ; operculum corneous. 



1. Action No^s. /. Sow. Tab. XIX, fig. 6, a — b. 



Action NoiE. J. Sow. Min. Conch, t. 374, 1822. 



— S. Wood. Catalogue 1842. 



Tornatella NoiE. Nyst. Coq. foss. de Belg. p. 424, pi. 37, fig. 22, 1844. 



A. Testa ovato-elongatd vel subcylindraced ; spird conoided ; anfractibus septem vel octo 

 convexiusculis, transversim slriatis ; suturis depressis, subcanaliculatis ; columella uniplicatd, 

 labro acido, intus sulcalo. 



Shell elongato-ovate, or subcylindrical, with a conical spire ; whorls slightly 

 convex, regularly striated, or rather sulcated, transversely ; suture deep, subcanali- 

 culated ; aperture linear ; outer lip sharp, with the strige visible within. 



Axis, 1 inch ; diameter, -fy. 



Locality. Red Crag, Walton Naze and Brightwell. 



This species is not very rare at the above locality, though, from its extreme 

 fragility, it is difficult to obtain in perfect condition. The shell appears to have 

 undergone a slight diminution in magnitude, and to have shrunk from the inner lip, 

 perhaps from the loss of a more than ordinary quantity of animal matter. It is 

 considered here as differing from A. tornatilis in having the spire rather shorter, 

 and a deeper and more distinct canal at the suture, which, however, might be pro- 

 duced by the shrinking of the shell ; but the upper part of the volution is more 

 rounded, and the strias are regularly distributed over the surface, sometimes single, 

 sometimes in pairs. In the recent British shell they are larger and coarser at the 

 base, and the fold upon the columella is smaller. The deep sulci of the exterior 

 are visible within at all ages from the thinness of the shell. Aperture three fourths 

 of the length of axis. 



*B" 



* Etym. Actceon, a proper name. 



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