The Moon Shells and Velvet Shells 



and "painted" moon shells, suggesting in their common names 

 their colouring and marking. 



Genus SIGARETUS, Lam. 



Shell ea-r-shaped, white, solid, flattened; spire lateral; 

 aperture oblique, flaring; operculum very small: umbilicus 

 wanting; foot very large, especially the burrowing part in 

 front. It lives in muddy sand flats of warm seas. 



S. perspectivus, Say, differs from the Naticas in form 

 and in its manners. The flattened white shell is shaped like 

 that of a Haliotis. It is called "ear shell," a good descriptive 

 name. The immense foot suggests its relation to the moon shells. 

 But the aggressive methods of the previous genus are a striking 

 contrast to the halting timidity of this one. It is a slow and 

 cautious citizen. It may well be apprehensive, for the body is 

 exposed to dangers unknown to Natica. When the foot is con- 

 tracted to the compass of the shell, the operculum is little or no 

 protection, for it is a thin button, by no means large enough to 

 cover the exposed surface of the body. 



This mollusk is a dainty morsel to the various "littoral pigs" 

 that root for their daily rations in the wet sand. In its turn, it 

 falls upon the oyster which is smothered by being enveloped 

 in the folds of the muscular body. 



Rare on northern beaches, it becomes more abundant as 

 we go down the Atlantic coast. A dotted form, S. maculatus. 

 Say, is met on the beaches of Florida. Length, i^ inches. 



Habitat. — New Jersey to Florida. 



The Frail Ear Shell (5. debilis, Gld.) is a very delicate, 

 shallow saucer of white china, with a small spire at one end. 

 The surface is beautifully cancellated. The creature lives just 

 under the sand. Its food is small bivalves. Length, i inch. 



Habitat. — Southern California. 



Genus LAMELLARIA, Montagu 



Shell ear-shaped, internal, thin, pellucid, spire small, lateral; 

 aperture large; operculum wanting. 



L. Stearnsii, Dall, is a thin, white, ear-shaped shell which in 

 life is quite swallowed up by the mantle. Length, about J inch. 



Habitat. — Monterey, Cal. 



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