centrali preelongo, postice fccto ; d. antico minore a margine 

 remoto, lamina totias longitudinis ad centralem juncto. 



Long. -()5, lat. 3, alt. -05 poll. 



Hub. in China et Borneo (Mus. Cuminy.). 



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

 ddicatulus 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 differences are probably due to increased 

 age only. 



4. CCELODON FLEXUO*US, Sby. (Pandora /.), Sp. Conch, f. 13, 

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



. . cardine v. dextra dente postico prcelongo, a margine separato t 

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

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

 ex t ante, retrorsum dejtecto ; d. ant. minimo, pene obsoleto : v. 

 sinistr. sulco prcelongo postico ; fossa cartilaginea separata^ 

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

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

 turn, porrecto. 



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

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

 long clavicle, forms an interesting transition to Clidiophora. 



4 a. 1 CCELODON UNGUICULUS, Sby. (Pandora u.), Sp. Conclu 

 f. 16, 17; Hani. 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.flexuosus, and, though the shape is somewhat different, perhaps 

 it is only a variety. 



Genus PANDORA, Lara. 



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 apply*. 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 type is the Tellina in&qualis of Linnaeus. 



1. PANDORA ROSTRATA, Lam., Forbes & Hani, et auct. plur.= 

 P. inagualis, Linn., Gray, Add. 



* 



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

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

 aplatie, bifurquee. dont la portion anterieure, plus longue, se prolonge jusqu'a 

 1'impression musculaire anterieure " a character which only belongs to the sec- 

 tion Ccelodou, 



230 



