70 



curved, thick, wrinkled ',fossule visible ; cardinal 

 tooth striated ; apices slightly prominent, decorti- 

 cated ; nacre smooth, saffron colour. 



REMARKS. 



When the ligament is mentioned in the prece- 

 ding pages, the great posterior one is alluded to ; 

 there is also an anterior membranous and folia- 

 ceous ligament in all these shells, which is very 

 small and short, in the elongated or rounded, 

 and larger or oblong, in the elliptical or dilated 

 shells. 



Having more carefully examined the species, 

 No. 48. Obovaria pachostea, vide page 51, I 

 have discovered that it belongs to the genus 

 Amblema, to which it must be united, its charac- 

 ters are as follow : 



Amblema antrosa, very thick, somewhat ven- 

 tricose, rounded, flexuous with a small lateral 

 sinus inferiorly ; epidermis brown, lamellar ; 

 nacre violaceous, pale, undulated, and a large 

 cavity under the bilobed (cardinal) tooth. Breadth 

 f diam. |- of the length ; axis almost terminal. 



