CHAPTER XIV: THE DOVE SHELLS 



Family CoLUMBELLiD/t 



Shell solid, small, ovately oblong or triangular, sometimes 

 fusiform; spire exserted; anterior canal short; columella arched, 

 tubercled below; outer lip thickened, uncurved at middle, toothed 

 on inner face; epidermis present; operculum horny; headlong, 

 eyes at base of tentacles, foot prolonged in front; mantle not 

 enfolding shell. Radula present, degraded, behind the head. 

 A family of few genera and many species. Little is known con- 

 cerning the living mollusks. Their distribution extends into both 

 warm and cold seas. 



Genus COLUMBELLA, Lam. 



Characters of the family. These handsome little mollusks 

 crawl upon sand flats and on gravelly and rocky shores in the 

 tropics and southward and northward to cold waters, in many 

 parts of both hemispheres. There are upwards of eight hundred 

 species named, but singularly, these have been erected upon shell 

 characters chiefly; few of the living mollusks have even been seen, 

 still fewer studied and figured. Lacking adequate knowledge, 

 conchologists are throwing into the genus Columbella shells having 

 the outer lip thickened and toothed on the inner edge. Study 

 of the soft parts of various species will doubtless make radical 

 changes in classification. 



The Common Columbella (C.mercatori a, Linn.) lives in sand 

 two to four feet below water level, The shell is solid, broad- 

 shouldered, with strong revolving ridges crossed by faint longi- 

 tudinal ones. The usual form is marked with streaks of brown 

 and white across the whorls. Pink specimens occur, of plain 

 colour or marked with fawn in irregular spots. In some forms 

 yellow, in others chocolate prevail. The aperture is white or 

 yellowish. Length, * to i inch. 



Habitat. — Florida and the West Indies. 



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