GASTEEOPODA. 



Family I. — NaticidvE. 



235 



Shell globular, few-whorled ; spire, small, obtuse ; aperture 

 semi -lunar ; lip acute ; pillar often callous. 



Fiff. 95. Natica.* 



Fig. 94. Natica monilif era ("Wilton). 



Animol with a long retractile proboscis ; lingual ribbon linear ; 

 rach is 1 toothed ; uncini 3 (as in Fig. 94) ; foot very large ; 

 mantle-lobes largely deyeloped, hiding more or less of the shell. 

 Species all marine. 



Natica (Adans.), Lamarck. 



Synonym, Mamilla, Schm. Cepatia, Gray. Nacca, Bisso. 



Type, N. canrena, PL YIII., Fig. 1. 



Shell thick, smooth ; inner lip callous ; umbilicus large, with 

 a spiral callus ; epidermis thin, polished ; oj)erculum sub-spiral. 



Animal blind ; tentacles connate 

 •with a head veil ; front of the large 

 foot provided with a fold {mentum), 

 reflected upon and protecting the head ; 

 operculigerous lobe large, covering 

 part of the shell ; jaws horny; lingual 

 ribbon short ; branchial plume single. 



The coloured markings of the naticse are very indestructible ; 

 they are frequently preserved on fossils. The naticoe frequent 

 sandy and gravelly bottoms, ranging from low water to 90 

 fathoms (Forbes). They are carnivorous, feeding on the smaller 

 bivalves (Gould), and are themselves devoured by the cod and 

 haddock. Their eggs are agglutinated into a broad and short 

 spiral band, very slightly attached, and resting free on the 

 sands. 



Bistrihution, 197 species. Arctic seas, Britain, Mediterranean, 

 Caspian, India, Australia, China, Panama, West Indies. 



Fossil, 260 species. Devonian — . South America, North 

 America, Europe, India. 



Suh-genera. Naticopsis, M'Coy. N. Phillipsii. Shell imper- 

 forate ; inner lip very thick, spreading ; operculum shelly 

 (British Museum). Carb. limestone, 7 species. 



* Fig. 95. Natica Alderi, Forbes. From an original drawing, communicated by 

 Joshua Alder, Esq 



