280 Mr. E. A. Smith on the Genus Sphenla. 



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 bp. 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 pacijica, De Folin. (PI. XV. A. fig. 7.) 



Sphenia pacificensis, De Folin, Les M6leagrinicoles, p. 15, pi. ii. 



figs. 10, 11. 

 Sphenia iiacijica, Martens, Zool. Rec. 1867, p. 586. 



Hah. Panama, on pearl-oysters. 



8. Sphenia Soioerhyi, sp. n. (PI. XV. A. fig. 8.) B.M. 



Testa paulo inaniuivalvis, postice rostrata, at aiigiiste hians, antico 

 rotundata, elongata, transversa, alba, epidermide tenui ]ira3cipue 

 margiuera versus induta ; valvse temies, mediocriter convexae, 

 coucentrice striata?, carina obliqua ab umbone usque ad extremi- 

 tatem posticam decurrente instructs ; margo dorsianticus obliquus, 

 areuatus, posticus concavus, ventralis late curvatus ; umbones 

 prominentes, fere mediani, ad apiccni antrorsum inclinati ; valva 

 dextra subedentula, sinistra dente compresso subquadrato mar- 

 ginali pone umbonem iustructa ; linea pallii infra cicatricem 

 posteriorem oblique descendcns, vix sinuata, 



Longit. 10| millim., alt. 6, diam. 4|. 



Testa junior minus elongata, baud rostrata. 



Longit. 7 millim., alt. 5, diam. 3g. 



Hob. Ariaucoupan, 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 iu naming that now 

 described. 



9. Sphenia similis, sp. n. (PI. XV. A. fig. 9.) B.M. 



Testa S, Soiverbyi similis, sed minor, angustior, carina umbonali 

 postica acutiore instructa, magis inajcjuilateralis, postice in rostro 

 longioreet latiore terminans, margine dorsali postico minus incur- 

 vato, ventrali minus arcuato. 



Longit. 8 millim., alt. 5, diam. 3^. 



Hah. ? 



Although very like the preceding species, I believe that the 

 present form is quite distinct. It is a longer and narrower 

 shell, with a longerj straighter, and broader rostrum, and the 



