GASTEROPODA. DBF 
LAMELLARIA, Montagu. 
Etymology, lamella, a thin plate. 
Synonyms, Marsenia, Leach. Coriocella, Bl. 
Type, L. perspicua. Pl. VIII., Fig. 6. 
Shell ear-shaped ; thin, pellucid, fragile; spire very small ; 
aperture large, patulous; inner lip receding. No operculum. 
Animal much larger than the shell, which is entirely con- 
cealed by the reflected margins of the mantle; mantle non- 
retractile, notched in front; eyes at the outer bases of the 
tentacles. Lingual wncini 3, similar; or one very large. 
Distribution, 10 species. Norway, Britain, Mediterranean, 
New Zealand, Philippines. 
Fossil, 2 species. Pliocene—. Britain (Crag). 
Narica, Recluz. 
Synonyms, Vanicoro, Quoy. Merria, Gray. Leucotis, Sw. 
Type, N. cancellata. Pl. VIII., Fig. 8. 
Shell thin, white, with a velvety epidermis; ribbed irregularly 
and spirally striated; axis perforated; operculum yery small, 
thin. 
Animal eyes at the outer base of the tentacles; foot with 
wing-like lobes. 
Distribution, 26 species. West Indies, Nicobar, Vanikoro, 
Pacific. : 
Fossil. 4 species, Gault—. (D’Orbigny.) Britain, France. 
VELUTINA, Fleming. 
Etymology, velutinus, velvety (from vellus, a fleece), 
Type, V. levigata. Pl. VIII., Fig. 7. 
aN 
Fig. 96. Velutina levigata (Warington). 
Shell thin, with a velvety epidermis ; Spire small; suture 
deep; aperture yery large, rounded; peristome continuous, 
thin. No operculum. 
Animal with a large oblong foot; margin of tae mantle 
developed all 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. Carnivorous, Lingual 
dentition (Fig. 96). It resembles that of trivia (Fig. 15, B); 
