124 MANUAL OP THE MOLLUSCA. 





SiGARETUs (Adans.), Lamarck. 



Syn.^ cryptostoma, Bl. Stomatia, Browne. 



Tij^pe, S. haliotoides. PI. VIII., fig. 4. J 



Shell, striated ; ear-shaped ; spii'e minute ; aperture very Avide, oblique 1 

 (not pearly). Operculum minute, horny, sub-spiral. '. 



The flat species are entirely concealed by the mantle when living ; the J 

 convex shells only partially, and they have a yellowish epidermis. The ante- 

 rior foot lobe {ynentum) is enormously developed. J» 



Distr., 26 sp. W. Indies, India, China, Peru. ^, 



Fossil, 10 sp. Eocene — . Brit., Prance, S. America. ' 



Suh-gemis, naticina. Gray. N. papilla, pi. VIII., fig. 3. Shell ventricose, ■' 

 thin, perforated. W. Indies, Ked Sea, China, N. Australia, Tasmania. 

 Eocene, Paris. 



Lamellaria, Montagu. 



Mym., lamella, a thin plate. 



Syn., marsenia, Leach. Coriocella, Bl. 



Type, L. perspicua. PI. VIII., fig. 6. 



Shell ear- shaped ; thin, peUucid, fragile ; spire very small ; aperture f 

 large, patulous ; inner lip receding. No operc. 



Animal much larger than the shell, which is entirely concealed by t] 

 reflected margins of the mantle ; mantle non-retractile, notched in front ; eyi 

 at the outer bases of the tentacles. Lingual uncini 3, simOar ; or one vei 

 large, 



Distr., 5 sp. Norway, Brit., Medit., New Zealand, Philippines. 



Fossil, '2,%-^. Miocene — . Brit. (Crag.) 

 Naeica, Recluz. 



Syn., vanicoro, Quoy. Merria, Gray. Leucotis, Sw. 



Type, N. cancellata. PI. VIII., fig. 8. 



Shell tliin, white, with a velvety epidermis ; ribbed irregularly, and spi- 

 rally striated; axis perforated. Operc. very small, thin. 



Animal, eyes at the outer base of the tentacles; foot with wing-like lobes. 



Distr., 6 sp. W. Indies, Nicobar, Vanikoro, Pacific. 



Fossil, 4 sp. Gault— (D'Orb.) Brit., France. 

 Velutina, Pleming. 



Etyra., velidinus, velvety (from vellus, a fleece). 



Type, V. Iffivigata. PI. VIII., fig. 7. 



Shell thin ; with a velvety epidermis ; spire small ; suture deep ; aperture f 

 very large, rounded ; peristome continuous, thin. No operc. | 



Animal with a large oblong foot ; margin of the mantle developed all j 

 round, and more or less reflected over the shell; gills 2; head broad; tentacles ' 

 subulate, blunt, far apart ; eyes on prominences at their outer bases, Cami- ■ 

 vorous. Lingual dentition like trivia (flg. 15, B.). 





