116 



MANUAL OF THE MOLLUSCA. 



Fossil, 7 sp. (PChallv. Brit.) Miocene—. S. Europe. \ 



Stih-'jenus, mcdea, Valenc. (D. personatum) outer lip thickened and denti- 

 culated ; inner lip with callous prominences. 



Harpa, Lam. Harp-shell. 



T>/pe, H. ventricosa. PI. VI., fig. 11. (=Buc. harpa, L.) ! 



Shell, ventricose ; with numerous ribs, at regular intervals; spi]-e smaU ; j 

 aperture large, notched in front. No operc. 



The animal has a very large foot, with the front crescent-shaped, and I 

 diidded by deep lateral fissures fr-om the posterior part, which is said to sepa- < 

 rate spontaneously when the animal is irritated. Mostly obtained fr'om deep- ] 

 water, and soft bottoms. 



Distr., 9 sp. INIam-itius, Ceylon, Philippines, Pacific. 



Fossil, 4 sp. Eocene — . Prance. 



CoLUMBELLA, Lam. 



Eti/m., diminutive of colmnha, a dove. 



Tyi^e, C. mercatoria. PI. VI., fig. ] 0. 



Shell, small ; with a long narrow aperture ; outer lip thickened (especi- ^ 

 ally in the middle), dentated ; inner lip crenulated. Operculum very small, \ 

 lamellar. 



Bistr., 200 sp. Sub-tropical. TV. Indies, Medit., India, GaUapagos, , 

 California. Small, prettily-marked shells ; li\dug in shallow water, on sandy ( 

 flats, or congregating about stones. (Adams.) •; 



Fossil, 8 sp. Miocene — . (The Brit. sp. are pisanice) . ■ 



Suh-gemcs. Columhellina, D'Orb. 4 sj). Cretaceous. France, India. 1 



Olr^a, Lam. Olive, rice-sheU. 



Type, 0. porphyria. PI. VI., fig. 16. Syn., strephona. Brown. 



Shell, cylindiical, polished ; spire very short, sutm-e channelled ; aper- 

 ture long, narrow, notched in front ; columella callous, striated obliquely ; 

 body whirl fiuTowed near the base. No operc. in the typical sp. 



Animal, with a very large foot, in which the shell is half immersed; 

 mantle lobes large, meeting over the back of the shell, and gi^^ng off filaments 

 which lie in the sutm-e and furrow. The eyes are placed near the tips of the 

 tentacles. 



The olives are very active animals, and can turn over, when laid on their 

 back ; near low water they may be seen gliding about or burying in the sands 

 as the tide retires ; they may be taken with aniuial baits, attached to lines. 

 They range downwards to 25 fms. 



Distr., 117 sp. Sub-tropical, W. and E. America. W. Africa, India, 

 China, Pacific. 



Fossil, 20 sp. Eocene — . Brit., France, &c. 



