1864. ] DR. P. P. CARPENTER ON THE PANDORID&. 601 
centrali prelongo, postice flecto; d. antico minore a margine 
remoto, lamina totius longitudinis ad centralem juncto. 
Long. °65, lat. °3, alt. -05 poll. 
Hab. in China et Borneo (Mus. Cuming.). 
This species is the Eastern representative of P. rostrata, as is C. 
delicatulus 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. CaLopon FLexvosus, Sby. (Pandora f.), Sp. Conch. f. 13, 
14,15; Hanl. Rec. Shells, p. 49 (diagn. auct.). 
...cardine v. dextra dente postico prelongo, a margine separato, 
usque ad cicatr. adduct. porrecto; fossa cartilaginea curta, 
inter dentes post. et centr. sita ; d. centr. curtissimo, maxime 
extante, retrorsum deflecto ; d. ant. minimo, pene obsoleto: v. 
sinistr. suleo prelongo postico; fossa cartilaginea separata, 
curtiore ; d. centr. extante, curtissimo, supra cavernam pyri- 
Sormem, 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 Arca. It is swollen and twisted, and, by its 
long clavicle, forms an interesting transition to Clidiophora. 
4a. ?Ca@.Lopon unGuicutus, Sby. (Pandora u.), 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. flecuosus, and, though the shape is somewhat different, perhaps 
it 1s only a variety. 
Genus Panpora, 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 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 inequalis of Linnzus. 
1. Panpora rostrata, Lam., Forbes & Hanl. et auct. plur.= 
P. inequalis, 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, 
aplatie, bifurquée, dont la portion antérieure, plus longue, se prolonge jusqu’a 
Vimpression musculaire antérieure ”—a character which only belongs to the sec- 
tion Celodon. 
