LORIPES. 233 



A. Shell concentrically ribbed and slightly decussated by lon- 

 gitudinal striae ; lateral teeth indistinct. 



1. Loripes lac'teus *, Linne. 



Tellina lactea, Linn. Syst. jSat. p. 1119. Lucina leucoma, F. & H. ii. 

 p. 57, pi. xxxv. f. 2 (as L. lactea). 



Body whitish : foot cylindrical, and swollen in the upper 

 part. 



Shell usually of a somewhat globular form, but varying in 

 comparative length and breadth, rather solid and opaque, not 

 glossy: sculpture, distant lines of growth and fine, irregular 

 and close-set concentric striae, as well as equally fine and irre- 

 gular but less numerous longitudinal striae or scratches, which 

 radiate from the direction of the beak, and cause the surface to 

 be partly decussated : colour white, with a tinge of yellow : 

 epidermis forming a mere film, and slightly iridescent : margins 

 rounded and sometimes indented or sinuous on the anterior 

 side, curved in front, and slightly truncate although rounded on 

 the posterior side : beaks small, rather prominent, much in- 

 curved and close together ; they are placed very nearly in the 

 middle of the dorsal margin : lunule deep and heart-shaped : 

 hinge-line flexuous, occupying about one-fourth of the circum- 

 ference : cartilage yellowish-brown, shaped like a lance -head, 

 divided into two semicylindrical portions, each of which fills a 

 groove on the hinge-plate in either valve, sloping obliquely 

 downwards from the beak within the line of the posterior 

 lateral tooth, and terminating abruptly in the interior of the 

 shell : hinge-plate broad and strong : teeth, in the right valve 

 one triangular cardinal, and occasionally a small denticle, be- 

 sides two indistinct laterals (one on each side), which are more 

 or less raised and pointed at the end ; in the left valve a 

 double cardinal, which receives that of the opposite valve in 

 an intermediate socket, and two laterals as in the other valve ; 

 the posterior lateral is much the longer : inside somewhat 

 nacreous, but of a dull hue ; margin smooth and plain : scars 

 large and remarkably distinct. L. 0*7. B. 07. 



Yar. Desmarestii. Shell flatter and thinner. Lucina Des- 

 marestii, Payraudeau, Cat. Moll. Corse, p. 44, pi. i. f. 19, 20. 



Habitat : Muddy gravel and sand on the coasts of 



* Milk-white. 



