114 MANUAL OF THE MOLLUSCA. 



Bistr., 1 sp. Sicily, adhering to corals. Closely allied to ptirpura\ 

 madrejiorarum, Sby. Chinese Sea. 



RicixuLA, Lam. \ 



Etym., dimunitive of ricmns, the (fruit of the) castor-oil plant. \ 



Ex., R, arachnoides. PI. VI., fig. 9 (=niiu-ex ricinus L.). ' 

 Shell, thick, tuberculated, or spiny ; aperture contracted by callous pro- \ 



jections on the Kps. Operc. as in purpura. ; 



Distr. 25 sp. India, China, Philippines, Australia, Pacific. ; 

 Fossil, 3 sp. Miocene — . France. 



Plan AXIS, Lam. | 



Ti/pe, P. sulcata. PI. VI., fig. 6. Si/n., quoyia and leucostoma. j 



Shell, turbinated ; aperture notched in front ; inner lip caUous, channel-J 

 led behind ; operculum suhspiral (quoyia) or semi-ovate. PI. VI., fig. 7- 



Dish'., 11 sp. W. Indies, Red Sea, Bom'bon, India, Pacific, and Peru, j 



Fossil, miocene ? 



Small coast shells, resembling perimnkles, with which Lamarck placed | 

 them. 



Magill-s, Montf., 1810. 



Syn., campulote, Guettard, 1759. Leptoconclius, RiippeU. 



Type, M. antiquus. PL V., figs. 19, 20. 



Shell, wheri young, spiral, thin; apertm-e channelled in front; adult,r 

 prolonged into an irregular tube, solid behind ; operculum lamellar. 



Distr., 1 sp. ? Red Sea. Mamitius. 



The magUus lives fixed amongst corals, and grows upwards with the I 

 growth of the zoophytes in which it becomes immersed; it fills the cavity of | 

 its tube with solid shell, as it advances. 



Cassis, Lam. Helmet-sheU. 



Syn., bezoardica, Schmn. Levenia, Gray. C}-pr0ecassis, Stutch. • j 



Ty2)e, C. flammea. PI. VI., fig. 14. ,j 



Shell, ventricose, with irregular varices ; spire, short ; aperture long, J 



outer lip reflected, denticulated ; inner lip spread over the body-whirl ; canal i 



shai-ply recm'ved. Operculum small, elongated ; nucleus in the middle of the ( 



straight inner edge. ' 



Distr., 34 sp. Tropical seas; in shallow water. W. Indies, Medit., 

 Africa, China, Japan, Australia, New Zealand, Pacific, Mexico. ! 



Fossil, 36 sp. Eocene — . Chile, France. ' 



The queen-conch (C. madagascariensis) and other lai-ge species, are used i 

 in the manufactm-e of sheU cameos, p. 46. The periodic mouths {varices) 

 which are very prominent, are not absorbed internally as the animal grows. 



OxisciA, Sowerby. 

 Etym., oniscns, a wood louse. Syn., morum, Bolten. 



