CARDIAD^E. 



67 



small ; margins smooth ; ligament internal ; teeth 

 t? i> i, or T, f, |. Animal with one siphon. 



K. suborbicularis. Fig. 102 ; n. s. 

 rubra. 



Turtonia (Hanley). Shell oblong, unequal- 

 sided ; ligament concealed between the valves ; 

 hinge-teeth f . Animal with one siphon, lengthened. 

 T. minuta. Fig. 103 ; mag. 



Diplodonta (Bronn.). Shell roundish, smooth ; 

 ligament double, rather long, sub-marginal ; hinge- 

 teeth f , the front tooth in the left valve, and the 

 hind one in the right, cleft ; muscular impressions 

 polished. Animal with the mantle-edges plain, 

 united ; siphons two, unfringed. 



D. rotundata. Fig. 104 ; n. , 



104 



Lucina (Bruguiere). Shell round, white; beaks 

 depressed; lunule distinct ; ligament oblique, semi- 

 internal ; teeth fc f , f , the laterals sometimes want- 

 ing; muscular impressions rough. Animal with 

 the mantle open ; siphons two, simple ; foot cylin- 

 drical, pointed, slightly heeled. 

 L. borealis. L. flexuosa. 



divaricata. leucoma. 



ferruginosa. spinifera. Fig. 105 ; 



n. s. 



FAMILY III. CAEDIADJE. 



Shell regular, heart-shaped, marked with alter- 

 nate ribs and furrows, radiating from the beaks ; 



F2 



