centrali prcplongo, pnsfice Jfpcto ; d. antico minore a margine 

 remoto, lamina totius lonyitudinis ad centralem juncto. 



Long, -(ia, lat. "3, alt. -0.) poll. 



llah. ill China et Borneo {Miis. Cuming.). 



This species is the Eastern representative of P. rostrata, as is C. 

 delicahdus of P. obtusa. It has the reverse dentition, the central 

 tooth being very long, and the anterior short, bridged over to meet 

 it at the whole length. In the Borneo shell, which is larger, the 

 anterior tooth is rather longer, with the front margin of the ceiling 

 more incurved ; but the diiferences are probably due to increased 

 age only. 



4. CcELODON FLEXuosus, Shy. {Pandora/.), Sp, Conch, f. 13, 

 14, 15; Hani. Rec. Shells, p. 49 (diagn. auct.), 



• . . cardine v. dextra dente postico prcelongo, a margine separata^ 



usque ad cicatr. adduct. porrecto ; fossa cartilaginea curia, 



inter denies post, et centr. sita ; d. centr. curtissimo, maxime 



extante, retrorsum dejiecto ; d. ant. minimo, pene obsoleto : v, 



sinistr. su/co prcBlongo postico; fossa cartilaginea separata, 



cvrtiore ; d. centr. extante, curtissimo, supra cavernam pyn- 



formem, in dentem anticum usque ad cicatr. adduct. prolonga- 



tum, porrecto. 



This long-known but rare Red Sea species is to Pandora what 



Trisis (Gray) is to Area. It is swollen and twisted, and, by its 



long clavicle, forms an interesting transition to Clidiophora. 



4 a.? CcELODON uNGuicuLtrs, Shy. {Pandora «.), Sp. Conch,' 

 f. 16, 17; HanL Rec. Shells, p. 49. 



The type has not been found of this species, which was described 

 from a convex valve only. It clearly belongs to the same section as 

 C fexuosus, and, though the shape is somewhat different, perhaps 

 it is only a variety. 



Genus Pandora, Lam. 



It is proposed to limit this genus according to the diagnosis of Sow- 

 erhv, founded on Lamarck's. Succeeding naturalists have adopted 

 the diagnosis, while they have included in it species to which it did 

 not af)ply*. It presents a very simple type of hinge, as though the 

 Pandorid idea were gradually fading away towards Myodora. The 

 P. wardinna is the finest species in the group ; but it is scarcely 

 tvpical, having the radiating grooves of the section Kemierlia. The 

 Lamarckian ty])e is the Tellina incequalis of Linnaeus. 



1. Pandora rostrata, Lam., Forbes & Hani, et auct. plur.= 

 p. incequaiis, Linn., Gray, Add. 



* Chenu, however (Man. Conch, ii. p. 51), gives an original and extended 

 diagnosis, in which he accredits to the whole genus " une dent triangulaire, 

 aplalie, bifurqiiee. dont la portion anterieure, plus longue, se prolonge jusqu'a 

 Timpression musculaire auteiieure " — a character which only belongs to the sec- 

 tion Cteludou, 



230 



