142 AMERICAN MARINE CONCHOLOGY. 



Family SOLENID^. 



Animal with a veiy large, more or less cylindrical foot ; siphons 

 short and united (in the typical species, with long shells) or longer 

 and partly separate in the shorter and more compressed genera; 

 gills narrow, prolonged into the branchial siphons. 



Usually living buried vertically in the sand. 



Synopsis of Oenera, 

 Shell very long, nearly straight, ends gaping, hinge terminal. One pri- 

 mary tooth in each valve. Pallial impression with a short square sinus. 



SOLEN. 



Shell very long, gaping and rounded at each end, beaks nearly terminal. 

 Hinge with two teeth in one valve, and three in the other. PalUal line 

 with a small, truncate sinus. Ensis. 



Shell transversely oblong, curved, rounded and gaping at the ends with a 

 rugose epidermis. Beaks sub-central, hinge teeth 2, 3. Sinus of pallial 

 impression very deep, extending beyond the umbo. Siliquakia. 



Shell transversely oblong, epidermis polished, ends rounded and gaping. 

 Hinge anterior to the middle, with three teeth in each valve. Pallial line 

 with a short, rounded sinus. Siliqua. 



Genus SOLEN, Linnaeus. 

 Syst. Nat., edit. x. 673. 1758. 



1. S. viRiDis, Say. Figs. 329, 330. 



Journ. Philad. Acad., ii. 316. 1822. 



Shell transversely oblong, compressed. Hinge margin nearly 

 straight; basal margin curved ; postex'ior end obliquely truncated, 

 a little reflected and rounded near the base ; anterior end rounded. 

 Smooth, with very slight concentric growth lines. Epidermis pale 

 green. 



Length 2 inches, height .4 inch. 



Neio Jersey Coast, soutJiwards. 



Genus ENSIS, Schumacher. 

 Essai, Nov. Gen. 143. 1817. 



Solen (part) Auct. 



1. E. Amertcanus, Gould. Fig. 331. 

 Invert. Mass., edit. ii. 42. 1870. 



Shell elongated, cylindrical, slightly curved, ends truncately 

 rounded. Epidermis glossy, with a long triangular space marked 

 by concentric growth lines, above and below covered with lines 



