130 SPECIFIC 



Lister Conch. Tab. 351. Fig. 189. 



Specimen clear white ; gape of the posterior 

 slope lanceolate, the circumference of which is 

 tumid and crenate; margin of the shell deeply 

 crenate ; hinge furnished with an anterior tooth 

 besides the usual callus. 



Inhabits the Indian Ocean. 



Fig. 3. Hinge of Arca granosa. 



Fig. 4. Arca tortuosa. 



Shell parallelopiped, striate ; larger valve ob- 

 liquely carinate. 



D'Argenville Conch. Tab. 19. Fig. 1. 



Specimen white; striated longitudinally and 

 transversely ; valves dissimilar, much twisted ; 

 margin subcrenate. 



Inhabits the Indian Ocean. 



Fig. 5. A. Nocc. 



Shell oblong, striated, emarginate at the apex, 

 beaks remote, margin gaping. 



Lister Conch. Tab. 368. Fig. 208. 



Specimen white and brown, rhomboidal ; exter- 



