GASTEROPODA. 31 



128. S. Isevigata, Lamark, Anim. sans vert., v., p. 584 ; Ver- 

 inetus roseus, Quoy, I.e., iii., p. 300. Shell small, cylindrical, obsoletely 

 ribbed, loosely convoluted, rugose. Pink or whitish. 



129. S. auStraliS, Quoy, I.e., \\\.,p. 302. Shell irregularly spiral, 

 sub-cylindrical, transversely rugose and obsoletely longitudinally 

 striated. White or yellowish white. 



FAMILY ONUSTIDJE. 



Shell conical, depressed; operculum large, sub-annular, horny; 

 muzzle conical, produced, eyes sessile ; foot small, dilated in front. 



PHORUS. 



Shell trochiform, concave beneath ; whorls flat, with foliaceous 

 margins to which stones, &c., are attached ; aperture very oblique, not 

 pearly, outer lip thin, much produced ; operculum imbricated, nucleus 

 external. 



Tropical seas. 



130. P_ onustus, Reeve ; T. agglutinans, Lamark, I.e., ix., p. 161. 

 Base finely spirally striated, umbilicus covered, margin waved ; upper 

 surface covered with stones, shells, corals, &c. Dirty white, base 

 brownish. Diameter of base about 2 inches. 



Pacific. 



FAMILY 



Shell limpet-like, with the apex more or less spiral ; interior 

 simple or divided by a shelly process, to which the adductor muscles 

 are attached. 



CALYPTRJSA. 



Shell obliquely conical, depressed ; apex sub-central ; whorls well 

 developed, covered with a horny lamellar periostraca ; nucleus spiral ; 

 base oblong, concave ; aperture very large, oblong, four-sided, not 

 quite so wide as the shell ; axis deeply concave on the right side of the 

 base. 



"West Indies. Chili. Europe. India. China. Japan. Philip- 

 pines. 



131. C. maCUlata, Quoy, I.e., iv., p. 422 ; O. dilatata, Gray, 

 Die/ 1 . N.Z., ii., p. 243. Shell .convex, oblique, conical, rather solid, 

 transversely striated. White, with a purple spot in the centre of the 

 interior ; outside covered with a brown rough periostraca. Diameter 

 of base, l - 5 inch. 



Common. Chatham Islands. 



TROCHITA. 



Shell conical, circular, spiral, thin. Apex central ; whorls several, 

 well developed. Base concave, circular. Mouth large, oblong, four- 

 sided. Axis central, imperforated, spiral, exposed to the apex of the 

 cavity. Periostraca horny, thin, lamellar. 



Magellan Straits. Falkland Islands. 



