CONCHOLOGY. 43 



A. glabrellum. A. subtruncatum. 



A. lucinale. A. solidum. 



A. Boysii. A. cordiforme. ' 



A. lenticulare. A. rupium. 



A. cancellatum. A. lamellosum. 



A. reticulatura. A. crenulatum. 



A. duplicatum. A. punctatum. 



A. laeve. A. multicostatum. 



A. prismaticum. A. siculum. 



FAMILY VI. 



CoRBULACEA. Two genera. 



1. Genus Corbjila. 

 Animal. Unknown. 



Shell. Tolerably solid, regular, inequivalve, inequilateral with 

 a conical, flexed, ascending, primary tooth in each valve ; a cavity 

 at the side ; no lateral teeth ; ligament interior, placed in the cavi- 

 ties ; two neighbouring muscular impressions. Inhabits the 

 British seas. Nine species. Four fossil. 



Corbula australis. Corbula taitensis. 



C. sulcata. C. nucleus. 



C. erythrodon. C. impressa. 



C. ovaUna. C. porcina. 



C. semen. 



2. Genus Pandora. 



Animal. Body much compressed, somewhat elongated, in 

 form of a furrow, in consequence of the union of the edges of the 

 mantle, and its continuation with the tubes, which are united and 

 short ; foot small, thickest in front, and issuing through a tolerably 

 large cleft in the mantle. 



Shell. Regular, white, elongated, much compressed, inequi- 

 valved, inequilateral ; right or upper valve quite flat, with a fold ; 

 summits feebly marked ; hinge anomalous, formed by a transverse 

 cardinal tooth on the right ; valve entering a corresponding cavity 



