CONCHIFERA. 299 



second and third in Venus and Cytherea ; the second tooth of the left valve 

 is consequently obsolete. 



Distr. C. Islandica ranges from Greenland and the U. S. to the Icy Sea, 

 Norway, and England ; in 5 80 fm. water. It occurs fossil in Sicily and 

 Piedmont, but not alive in the Medit. 



Fossil, 90 sp. (D'Orb.) Muschelkalk . Europe. 



CIRCE, Schumacher. 



Etym. In Greek myth, a celebrated enchantress. 



Ex. C. corrugata, PL XX. fig. 2. Syn. Paphia (undulata) Lam.* 



Shell sub-orbicular, compressed, thick, often sculptured with diverging 

 striae ; nmbones flat ; lunule distinct ; ligament nearly concealed ; margins 

 smooth; hinge-teeth 3:3; laterals obscure; pallial line entire. 



Animal (of C. minima} with the mantle open, margins denticulate, 

 siphonal orifices close together, scarcely projecting, fringed; foot large, 

 heeled; palpi long and narrow. Ranges from 8 50 fms. (Forbes.) 



Distr. 37 sp. Australia, India, Red Sea, Canaries, Brit. 



ASTARTE, Sowerby, 1816. 



Syn. Crassina, Lam. Tridonta, Schum. Goodallia, Turton. 



Ex. A. sulcata, PL XX. fig. 1. (Astarte, the Syrian Venus.) 



Shell sub-orbicular, compressed, thick, smooth or concentrically fur- 

 rowed; lunule impressed; ligament external; epidermis dark: hinge-teeth 

 2:2, the anterior tooth of the right valve large and thick ; anterior pedal 

 scar distinct ; pallial line simple. 



Animal with mantle open ; margins plain or slightly fringed ; siphonal 

 orifices simple ; foot moderate, tongue- shaped ; lips large, palpi lanceolate ; 

 gills nearly equal, united behind, and attached to the siphonal band. 



Distr. 14 sp. Behrings Sea, Wellington Channel, Kara Sea, Ochotsk, 

 U. S. Norway, Brit. Canaries, ^gean (30112 fms.) 



Fossil, 200 sp. (D'Orb.) Lias . N. and S. America, Europe, Thibet. 



? Digitaria, Wood ; Tellina digitaria, L. Medit. Fossil, Crag, Brit. 



CRASSATELLA, Lamarck. 



Syn. Ptychomya, Ag. Paphia (Lam. part) Roissy. 

 Type, C. ponderosa, PL XXI. fig. 4. Etym. Crassus thick. 

 Shell solid, ventricose, attenuated behind, smooth or concentrically fur- 

 rowed ; lunule distinct ; ligament internal ; margin smooth or denticulated ; 



* This name was employed by Bolten, in 1798, for sp. of Veneridae, and by 

 Lamarck, in 1801, for Venus divaricata, Chemn. (= Circe divaricata and Crassatella 

 contraria) and Mesodesma glabratum. In 1808, Fabricius adopted the name fora 

 group of butterflies, in which sense it is now widely employed, having been aban- 

 doned by Lamarck in his later works, and by all succeeding malacologists. 



