226 



MANUAL OF THE MOLLUSCA. 



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

 tralia, Pacific. 



Fig. 87.* 



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



Sub-genus, Malea, Yalenc. (D. personatum), outer lip 



thickened and denticulated ; inner lij) with callous prominences. 



Habpa, Lam. Harp-shell. 



Type, H. Tcntricosa. PI. YI., Fig. 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 hy 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. 



Distribution, 12 species. Mauritius, Ceylon, Philippines. 

 Pacific. 



Fossil, 4 species. Eocene — . France. 



COLTJMBELLA, Lam. 



Etymology, diminutive of columba, a dove. 



Type, C. mercatoria. PL VI., Fig. 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. The 

 1 roto.scis is exserted, and the siphon recurved over the front of the shell. 



