NATICELLA. 211 



C. corrugata. Lam. Eu. Meth. 248. f. 8, picta. Sw. En. Metb. 

 248. f. 6." Sw. p. 379. PI. viii. fig. 148. 



NANINIA. Gray. A genus composed of the planorbicular species 

 of Helix, with large umbilici, and outer Hp thin, included in 

 the sub-genus HeliceUa, Fer. Ex. H. citrina. PI. xiv. fig. 280. 



NASSA. Lam. A genus of small shells united to Buccinum by 

 some authors, but separated by others on account of the little 

 tooth-like projection terminating the columella. N. arcularia. 

 PI. xix. fig. 423. 



NATICA. Brug. Fam. Neritacea, Lam, Hemicyclostomata, Bl. 

 — Descr. Grlobose, thick, generally smooth ; spire short, pointed, 

 with few volutions ; aperture semilunar, entire ; outer lip thin ; 

 coliuneUar lip oblique, nearly straight, callous ; umbilicus with a 

 spiral callosity, termiaating behind the columella, and sometimes 

 fillin g up the cavity ; operculum shelly in some species, horny 

 in others ; epidermis thin, light, semitransparent. — 06s. The 

 straight, callous, smooth edge of the columella and the callosity 

 serve to distinguish this genus from Nerita, Neritina, Neritopsis 

 and Helix. PI. xv. fig. 327, 328. 



NATICAEIA. Sw. A sub-genus of Natica, thus described : 

 " Oval ; convex above ; umbilicus small, open, placed very near 

 the top of the aperture ; inner Hp reflected ; small. N. melanos- 

 toma, Mart. 189. f. 1926, 1927. cancellata, Sw, lb. 189. f. 1939. 

 bifasciata, Griff. Cuv. 1. f. 2." Sw. p. 346. 



NATICELLA. Guild. A sub-genus of Natica, thus described : 

 " Operculum horny ; shell globose, but generally depressed ; 

 umbilicus nearly filled up by a vitreous deposition of the inner 

 lip ; spire obtuse. N. aurantia. Mart. 189. f. 1934, 1935." Sw. 

 p. 345. 



NATICELLA. Lamarck, 1822. Catillus, Humphrey (named 

 in a catalogue) 1817. Cimbee, Montf. 1810. (A little ship.) 

 Fam. Neritacea, Lam. Hemicyclostomata, Bl. — Descr. Trans- 

 versely oval, symmetrical, smooth ; aperture entire, oval ; dorsal 

 surface convex ; outer lip thin ; inner lip flat, straight edged ; 

 spread over the front surface of the body whorl, and sometimes 

 hiding the apex; apex incurved; operculum testaceous, flat, 



p2 



