MARINE MOLLUSCA OF THE UNITED STATES. 17 



Family STROMBID^E. 



Animal furnished with large eyes, placed on thick pedicels ; 

 tentacles slender, rising from the middle of the eye-pedicels. Foot 

 narrow, ill-adapted for creeping. 



The strombs are carrion-feeders, and for molluscous animals, 

 very active ; they progress by a sort of leaping movement, turn- 

 ing their heavy shells from side to side. Their eyes are more 

 perfect than those of the other gasteropods, or of many fishes. 



Genus STBOMBUS, Linn. 

 Syst. Nat., edit. ii. 64. 1740. 



Shell rather ventricose, tubercular or spiny ; spire short ; aper- 

 ture long, with a short canal above and truncated below ; outer 

 lip expanded, lobed above, and sinuated near the notch of the 

 anterior canal. 



The fountain-shell of the West Indies, S. gigas, L., is one of 

 the largest living gasteropods, weighing sometimes four or five 

 pounds. Immense quantities of it are annually used for the manu- 

 facture of cameos, and for the porcelain works; 300,000 were 

 brought to Liverpool from the Bahamas in one year. There are 

 about seventy -five species ; inhabiting all tropical seas. 



1. S. ALATUS, Gmelin. Fig. 16. 



Syst. Nat. 3513. 1790. 

 Strombus pyrulatus, Lamarck, Anim. s. Vert. vii. 205. 1822. 



Shell ovately conical, rather stout, spire acuminated, whorls 

 smooth, conspicuously grooved at the base and towards the apex, 

 concave round the upper part, noduled at the angle, nodules 

 rather small, columella very callous, lip winged, interior of the 

 aperture wrinkled towards the lip ; chestnut-brown, columella, and 

 interior of the aperture deep blackish-chestnut, sometimes carne- 



lian-red. 



Beaufort, North Carolina, to West Indies. 



Genus APOKRHAIS, Dillwyn.* 

 Philos. Trans., ii. 395. 1823. 



Shell with an elongated spire; whorls numerous, tuberculated; 

 aperture narrow, with a short canal in front ; outer lip of the adult 

 expanded and lobed or digitated ; operculum pointed, lamellar. 



* On the authorship of this name see W. M. Gabb in Am. Journ. Conch. , 

 iv. 143. 1868. 

 2 



