RISSOA. 39 



D. SiDirally striated, or smooth ; outer lip plain. 

 19. R. PRox'iMA"^, Alder. 



E. pro.vima (Alder), F. & H. iii. p. 127, pi. Ixxv. f. 7, 8, 



Body brilliant and almost clear white, dotted with minute 

 opaque-white flakes : mantle even, and (as well as the next 

 species, R. vitrea) not exhibiting the usual filamental process : 

 snout somewhat cylindrical and extensile, quite smooth and 

 rounded at its extremity, where it forms a rose -like disk ; when 

 fully extended it is blotched at the sides and on the tip with 

 claret-red : tentacles rather short, flat, strong, tapering, and 

 minutely bulbous at the tips, each of which is clothed with 

 six comparatively long and fine needle-shaped hairs : eyes re- 

 markably lai^ge, black, and placed on minute and nearly 

 semicircular lateral excrescences at the outer bases of the ten- 

 tacles, which are so amalgamated with them as scarcely to 

 present any prominence : foot large, fleshy, grooved and slightly 

 labiated in front, with a deep notch^or indentation, and ex- 

 panded into large, long, arched, and pointed auricles ; it is 

 divided behind into two long distinct and diverging tails or 

 streamers : opercular lobe close to the point of such bifurcation, 

 and destitute of a caudal cirrus. (Clark.) 



Shell closely resembling the next species {R. vitrea) in 

 shape and size ; but it is never lustrous ; and when examined 

 with even a low magnifying power, instead of being smooth 

 it is seen to be encircled by numerous distinct and rather spiral 

 striae; the colour is snow-white beneath a pale-yellowish 

 epidermis ; the spire tapers more gradually, and has a some- 

 what abruptly truncated apex ; the whorls are compact, and 

 not loosely coiled ; the inner lip is more closelj' attached to 

 the pillar ; and the operculum is white, formed of 4 or 5 volu- 

 tions, and marked w4th delicate striae in the line of growth. 



Habitat : Exmouth, eight miles from shore, in 15 f., 

 on a bottom of shells and mud (Clark) ; Torbay and 

 Plymouth, in 15-20 f., with R. vitrea (J. G. J.) ; Fal- 

 mouth (Barlee) ; Helford (Hockin) ; Cork, Bantry, and 

 Dul)lin (J. G. J. and others). Mr. Searles Wood has 

 lately found two specimens in the Coralline Crag at 



* The nearest, i. e. to E, vitrea. 



