The Top Shells and Dolphin Shells 



columella. The surface is white overlaid with brown and purplish 

 spots; the ribs set with rows of small white enameled beads. 

 It occurs as far north as Cape Hatteras, and follows the coast 

 to Texas and Vera Cruz. 



Many other species occur on our Atlantic coast, but they are 

 either rare or are deep sea forms, not often collected. 



C. granulatus, Born., of European seas is a thin, delicate 

 species, with exceedingly sharp peak, inflated base, and whorls 

 closely sculptured by thread-like riblets; those next to the sutures 

 are set with fine beading, which gives the surface a granular 

 appearance. It is also shiny, with pinkish ground freckled with 

 brownish yellow. The pearly substance is easily exposed by 

 rubbing off the outer layer with a rag dipped in dilute acid. An 

 inch or more in altitude, it is the largest granular species to be 

 found in Europe. 



The Tiger Top Shell (C iigris, Martyn) is two inches in 

 altitude, and banded with tawny colour on the paler and fine 

 granular whorls. It has a depressed spire with an abruptly sharp 

 point, and flares at base into an unusually large body whorl. 

 The bright colouring and striking pattern of the shell will keep 

 it always a cabinet favourite. New Zealand, Australia. 



Genus MARGARITA, Leach 



Shell very small, thin, depressed, globose, with smooth or 

 cross-striated whorls; aperture circular. 



The^A^avy Top Shell (M.undulata, Shy.) is a tiny mollusk, 

 scarcely J inch high. It exists in quantities along the New 

 England coast where it is appreciated as an edible mollusk by 

 the codfish and its relatives. It is abundant in their stomachs 

 at various seasons. At times of very low tide the collector may 

 look for this species among the rocks of sheltered coves. The 

 flattened dome is made of four rounded reddish whorls. The 

 columella has a deep, wide umbilicus; the body whorl has many 

 folds along its outer edge. 



M. cinerea, Couth., is a tiny dull greenish shell with fine 

 lines on the lower edge of the square-shouldered whorls and strong 

 ridges on the upper edge. Very fine and close-set oblique lines 

 cross the ridges throughout. It is found from Cape Cod north- 

 ward in shallow water. 



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