MOLLUSC A. 31 



The whorls of this species are concave and arcuately ribbed, the ribs being characterized 

 by two rows of nodules at the upper part, and one below. 



9. OLIVA, Bruguiere. 



1. Oliva fulgurata. PI. X. Kg. 12. Oliv. testa fusiformi, laevissinia, nitente, spira acuminata, 

 columella arcuata, parurn sulcata, truncata, apertura oblonga, labro subdilatato ; albida, castaneo longitu- 

 dinaliter conspicue fulgurata, columella castaneo-rufo fasciata. 



Hab. China Sea. 



A highly polished shell, very conspicuously painted with longitudinal, zigzag, chestnut 

 bands upon a whitish ground, the columella having a reddish tinge of colour. 



10. ANCILLARIA, Lamarck. 



The animal of Ancillaria is voluminous, covering the entire shell, with the exception of the 

 spire. The head, which is entirely concealed by the reflected portions of the foot, consists of 

 a short, inflated, cylindrical, annulated proboscis, above which is a semilunar veil formed by 

 the dilatation and union of the tentacles ; there is no indication of eyes. The mantle lines the 

 shell, and is produced anteriorly into a long siphon. The foot is large and bursiforin, the 

 side-edges being greatly extended and reflected over the shell, meeting in the middle on the 

 back. As in Oliva, it is deeply fissured anteriorly, forming a semilunar disc before the head, 

 divided by a deep longitudinal groove into two lateral, triangular lobes, acuminated transversely; 

 posteriorly it is bilobed, and is either without an operculum, or is provided with a thin, 

 horny, unguiform one, with apical nucleus, semilunar striee, and an oval muscular impression. 



1. Axcillaria obttjsa. PI. XIII. Pig. 6 a, b. Swainson, Journ. Sci. Lit. and Arts, vol. xviii. p. 2S2. 

 Sowerby, Species Conchyliorum, Anc. p. 5. Pig. 24, 25. 



Hab. East coast of Africa, below Port Natal. 



The specimen taken alive at the above-named locality was of a dirty white colour, 

 marked with dull brown, elongated blotches, distributed with scarcely so much regularity as 

 represented in our figure. Fig. 6 b represents the operculum. 



The Ancillarice resemble the Oliva in their habits, dwelling among the smooth sands in which they 

 frequently bury themselves. They crawl with a quick sliding motion, and, as they glide briskly along, the 

 tubular cylindrical siphon only is visible, directed backwards and upwards, and even laid flat upon the 

 back ; the alar expansions of the foot slightly overlap each other in the middle, and, extending considerably 

 beyond the spire, form posteriorly a loose open sac. It is possible that the dilated lobes of the foot 

 are sometimes extended and serve for swimming, as D'Orbigny has observed in Oliva Tehuelchana, Yoy. 

 Amer. Me'rid. Moll. p. 419. A. A. 



