eevfrnfi prrpJnvgn, pn.^ficf forto ; &. anttro r.rinnre a margins 

 remoto, lamina totius lomjitiidinis ad centralem juncto. 



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



Jlah. ill China et Borneo {Mas. Cuming.). 



Tills species is the Eastern representative of P. rostrafa, as is C. 

 delicafiilus of P. ohtusa. It has the reverse dentition, the central 

 tooth beiiie; 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. CfELODON FLEXUo?us, Shy. {Pandora/.), Sp. Conch, f. 13, 

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



• . . cardine v. dextra dente posfico prcelongo, a margine separato, 

 usque ad cicatr. addnct. porrecto ; fossa cartilaginea curta, 

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

 extante, retrorsum dejlecto ; d. ant. tninimo, pene obsolete : r. 

 sinistr. sulco prcelongo postico ; fossa cartilaginea separata^ 

 cirrtiore ; d. centr. extante, curtissimo, supra cnvernam pyrt- 

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

 turn, porrecto. 



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

 Trisis ((jray) is to Area. It is swollen and twisted, and, by ita 

 long clavicle, forms an interesting transition to Clidiophora. 



A a. 1 CcELODON UNGuicuLUS, Sby. {Pandora «.), Sp. Conch; 

 f. 16, 17 ; Ilanl. 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.fexiiosus, 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- 

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

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

 not afiply *. It presents a very simple type of hinge, as though the 

 Pandorid idea were gradually fading away towards Myodora. The 

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

 typical, having the radiating grooves of the section Kennerlia. The 

 Lamarckian ty])e is the Teltina "ttqualis of Linnaeus. 



1. Pandora rostrata. Lam., Forbes & HauL et zt, plur.^ 

 P incequalis, Linn., Gray, Add. 



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

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

 aplatie, hifurquee. dont lu portion anterieiire, j)lus tongue, se prolonge jusqu'a 

 rimpression niusculaire auttncure " — a character which ouly hclonjjs to the sec- 

 tion Cte/oi/oq. 



230 



