CONCHYLIA—DIT// Fi24. 52. 237 



Turton, Linn. Syst. iv. p. 287. 

 Chemnitz, viii. p. 106, tab. 78, fig. 71-3. 

 Dillwyn, Descript. Catal. p. 296. 

 Turton, Conch. Diet. p. 5, tig. 42, 4-3, 44. 

 Lister, Conch, tab. 211, fig. 46. 

 Mus. nosf. Found on Teignmouth beach. 



Shell nearly an inch and a quarter long, and an inch broad^ 

 convex, of a blackish horn-color, inflected and smooth at the 

 sides, longitudinally striate on the disk, with the beak of the 

 upper valve elongated curved aud pointed. 



.52. DISCW X— LAMARCK. 



Testa ina'qnivalvis ovatd-orbiculari, depressiuscula, Jixa ; 

 rated utruque disco centrali orbiculato. Discus valvoi su- 

 jjerioris medio submamillatus, inferioris rimd transversa 

 divisus. Cardo indistinctus. Ligamentum internum. 



Shell inequivalve, roundish-oval, rather flat, and fixed; each 

 valve furnished with an orbicular central disk. The disk of 

 the upper valve papillary near the middle, of the under valve 

 divided by a transverse cleft. Hinge indistinct. Ligament 

 internal. 



