170 BIVALVES. 



]y heart-shaped ; slightly striated transversely ; 

 posterior depression cordiform ; inner margin 

 crenated ; the outside is greyish or brownish, the 

 inside is white, with a violet-coloured spot at the 

 anterior side ; the length is about two inches and 

 three-quarters, the breadth about three inches 

 and a half. 



The Indians of North America cut these shells 

 into beads, some white and some black ; of these 

 they form their wampum, or treaty-belts, which 

 are symbolical of friendship. They also string 

 them together and use them for money. The 

 females cover the shoes they wear in dancing with 

 these shells, which in their movements being 

 struck together produce a sound resembling the 

 tinkling of the bells used by the Israelitish 

 women, and mentioned in Isa. iii. 16. 



VENUS Dysera* 



RIBBED VENUS. 



Specific Character. Shell triangular, convex, 

 heart-shaped, marked with distinct concentric 

 raised ridges, which are closely cancellated ; -f 

 the longitudinal striae are also crossed by fine 



* Plate VIII. figure 8. 



f Cancellated, crossed like the bars of a window, from 

 the Latin cancelli, lattice. 



