CORALLIOrHAGA. 439 



the anterior side; ligament external. Pallial impression 

 indistinct. 



Si/n. Libitina, Schum. Cypricardia, Lam. 



Ex. T. rostratum, Lamarck, pi. 109, fig. 5. Shell, T. 

 angulatnm, Lamarck, fig. 5, a, 5, b. 



The Australian region seems to be the chief locality for 

 the Trapezia, six species having been found in that 

 part of the globe, while but two are from Asia, and none 

 in Europe, Africa, or America. 



Species of Trapezium. 



angulatum, Lam. oblongum, Linn. 



Californicum, Conr. roseum, Gould. 



Guinaicum, Chem. rostratum, Lam. 



incarnatum, Reeve. solenoides, Reeve. 



liratum, Reeve. vellicatum, Reeve. 

 obesum, Reeve. 



Genus CORALLIOPHAGA, Blainville. 



Shell transversely oblong or sub-cylindrical, thin, slightly 

 gaping posteriorly ; valves white, with rather distant, 

 elevated lamelhe. Hinge with two primary teeth in each 

 valve, and a lamellar posterior lateral tooth. Pallial lino 

 with a wide, shallow sinus. 



St/n. Lithophagella, Gray. 



Ex. C. coralliophaga, Gmelin, pi. 109, fig. G, G, a. 



The species of this genus are found living in coral, or 

 imbedded in other shells. 



Species of Coralliophaga. 



coralliophaga, (riuel. lithophagella, Lam. 



decussata, Reeve. serrata, Reeve. 



laminata, Reeve. 



