COLUMBELLIDAE AND NaSSARIIDAE 161 



more than half of height, sutures distinct; fine equidistant spiral 

 striations, much stronger over lower portion of shell; aperture nar- 

 row, length of body whorl; outer lip thickened, its inner margin with 

 a central convexity, crenulate with purple stain in intervening 

 sulci; columella curved, deep notch near base, denticulate below 

 with dark stain between teeth; operculum corneous, small. 



Shallow water. Often among grasses and about old pilings. 



Family NASSARIIDAE 



The family Nassariidae is represented in all seas. They are 

 small animals but none the less destructive of other molluscan life 

 through their carnivorous appetites and predatory habits. Animals 

 of Nassarius vibex have been seen by Perry to pierce the egg cap- 

 sules of Cantharus jloridanus and devour the contents. 



The shells are ovate, more or less rotund with acuminate spire, 

 short anterior canal and extensive columellar callus. The operculum 

 is corneous, unguiculate, its edges often irregular or serrate. 



Genus NASSARIUS Dumeril, 1806 

 Jfassarias ambiguus antillamm^s^ (d'Orbigny) PI. 32, fig. 229 



Alt., 15 mm.; spire, 9 mm. Shell conic-ovate, cream-white with 

 scattered brown markings in interrupted spiral bands, often a dark 

 band at sutures; thin epidermis; seven whorls, shoulders almost at 

 right angles to vertical axis of shell; whorls strongly ribbed from 

 apex to base, 11 ribs on body whorl; overlaid spiral sculpture of 

 closely placed ridges; aperture oval, outer lip thick in adult, thin 

 in juvenile specimens, sharply crenate within, with smaller marginal 

 denticulations; columella arcuate, small horizontal plications, pro- 

 nounced callus; anterior canal open, recurved. 



Dredged in four to six fathoms. 



Nassarius consensus^ss (Ravenel) PI. 32, fig. 230 



Alt., 12-14 mm. Cream-white with faint markings of purplish 

 brown, darkest between ribs; spire half height of shell; seven ribbed, 

 convex whorls; about nine ribs on body whorl; fine spiral threads 

 cross ribs and interspaces; aperture oval, strong varix posterior to 



-^'^ Lat., nassa, a basket for catching fish; ambiguus, wavering; of the 



Antilles. 

 298 Lat., consensus, agreement. 



