280 Mr. E. A. Smith on the Genus Sphenia. 
hinge. He says, “In every respect, except the position of 
the lamellar tooth in the hinge of the left valve instead of the 
right, the shell appears to be a true Sphenia.” In Mr. Blan- 
ford’s figure the “ lamellar tooth” is properly depicted in the 
left valve; in specimens of this species in the British 
Museum it is also in the left, and in every other species and 
specimen examined by the writer it is in the same valve. 
7. Sphenia pacifica, De Folin. (PI. XV. A. fig. 7.) 
Sphenia pacificensis, De Folin, Les Méléagrinicoles, p. 15, pl. ii. 
meget TKO WL 
Sphenia pacifica, Martens, Zool. Rec. 1867, p. 586. 
Hab. Panama, on pearl-oysters. 
8. Sphenia Sowerby?, sp.n. (Pl. XV. A. fig. 8.)  B.M. 
Testa paulo inequivalvis, postice rostrata, et anguste hians, antice 
rotundata, elongata, transversa, alba, epidermide tenui preecipue 
marginem versus induta; valve tenues, mediocriter convexe, 
concentrice striate, carina obliqua ab umbone usque ad extremi- 
tatem posticam decurrente instructz ; margo dorsianticus obliquus, 
arcuatus, posticus concavus, ventralis late curvatus; umbones 
prominentes, fere mediani, ad apicem antrorsum inclinati; valva 
dextra subedentula, sinistra dente compresso subquadrato mar- 
ginali pone umbonem instructa; linea pallii infra cicatricem 
posteriorem oblique descendens, vix sinuata. 
Longit. 104 millim.,, alt. 6, diam. 43. 
Testa junior minus elongata, haud rostrata. 
Longit. 7 millim., alt. 5, diam. 33. 
Hab. Aviancoupan, near Pondicherry. 
In the right valve the hinge-margin immediately in front 
of the umbo is somewhat thickened, but the incrassation is 
hardly enough to be termed a tooth, 
Specimens of this and the following species have been 
presented to the British Museum by Mr. G. B. Sowerby, 
after whom I have much pleasure in naming that now 
described. 
9. Sphenia similis, sp. n. (Pl. XV. A. fig. 9.) B.M. 
Testa S. Sowerbyt similis, sed minor, angustior, carina umbonali 
postica acutiore instructa, magis inequilateralis, postice in rostro 
longiore et latiore terminans, margine dorsali postico minus incur- 
vato, ventrali minus arcuato. 
Longit. 8 millim., alt. 5, diam. 33. 
Hab. fa 
Although very like the preceding species, I believe that the 
resent form is quite distinct. It is a longer and narrower 
shell, with a longer, straighter, and broader rostrum, and the 
