226 MANUAL OF THE MOLLUSCA. 



Bistrihution , 14 species. Mediterranean, Ceylon, China, Aus- 

 tralia, Pacific. 



Fig. 87.» 



Fossil, 7 species. (? Chalk. Britain). Tertiary. South Europo. 



Suh-genm, Malea, Yalenc. (D. personatum), outer lip 



thickened and denticulated ; inner lip with callous prominences. 



Harpa, Lam. Harp-shell. 



Type, H. ventricosa. PL Yl., Pig. 11. (— Buc. harpa, L.) 



Shell ventricose, with numerous ribs, at regular intervals ; 

 spire small ; aperture large, notched in front. No operculum. 



The animal has a yery large foot, with the front crescent- 

 shaped, and divided by deep lateral fissures from the posterior 

 part, which is said to separate spontaneously when the animal 

 is irritated. Mostly obtained from deep water and soft bottoms. 



Distrilution^ 12 species. Mauritius, Ceylon, Philippines. 

 Pacific. 



Foseily 4 species. Eocene — . Prance. 



CoLUMBELLA, Lam. 



Etymology^ diminutive of columha, a dove. 



Type, C. mercatoria. PL VI., Pig. 10. 



Shell small, with a long narrow aperture ; outer lip thickened 

 (especially in the middle), dentated ; inner lip crenulated. 

 Operculum very small, lamellar. 



Distribution, 205 species. Sub-tropical. "West Indies, Medi- 

 terranean, India, Gallapagos, California. Small, prettily- 



* D. perdix, L. species. § natural size (after Quoy). Vanicoro, Pacific. Tlie 

 1 tobo*cis is exserted, and the siphon recurved over the front of tlie shell. 



