LUCINAD^. 



65 



Astarte (SowerLy). Shell roundish, flattened, 

 thick; Imiule distinct; hinge-teeth |.; the front 

 tooth in the right valve large and thick. Animal 

 with the siphojis not fringed. 



A. arctica. 



compressa. 

 crebricostata, 

 elliptica. Fig. 96 ; n. s. 



A. Scotica. 

 sulcata, 

 triangularis. 



98 



^Jd 



100 



Circe (Schum.). Shell nearly as Astm-te.hvii the 

 hinge-teeth |. Animal with fringed siphonal ori- 

 fices, scarcely projecting ; foot large, heeled. 



C. minima. Fig. 97 ; n.s. 



Cyprina (Lamk.). Shell oval, large, strong; 

 ligament prominent ; no Imiule ; teeth y, f' o • Ani- 

 mal with fringed siphons, short, but projecting. 



C. Islandica. Y\g.^'^\ \u.s. 



Family II. Lucinad^. 



Shell roundish, closed ; interior dull, obliquely 

 furrowed ; ligament inconspicuous or sub-internal; 

 muscular impressions lengthened, rough ; pallial 

 line simple. Animal with the mantle-leaAX-s 



F 



