36 THE VOYAGE OF H.M.S. CHALLENGER. 



Section B. — Subgenus Cardiomija , A. kA-M\\s = Spathophora, Jeffreys. 



Teeth. — Same as in {Necera proper) Section A. 

 Cartilage. — Less oblique than in the above. 

 Surface. — Eadiately costate or Urate. 



NecBva goukUana, Hinds. 

 costeUata, Deshayes. 

 fallax, n. sp. 

 pectinata, Carpenter. 

 costata, Sowerby. 



Section O. 



Necera concinna. Hinds. 

 striata, Jeffreys. 

 curta, Jeffreys. 

 multicostata, Verrill and 

 Smith.* 



Teeth of right valve, Cartilage-Pit, and Sculpture, the same as in Section A, but a 

 small erect posterior lateral tooth is present in the left valve. 



Necera pulchella, H. Adams. 



Section D. 



Teeth. — One small lateral tooth on each side near the beak in both valves (the 

 anterior in the left being feeble). 



Cartilage and Surface as in A and B. 



Necera singaporensis, Hinds. 



Section E. 



Teeth. — A short lateral tooth on each side in the right valve, with coiresjjonding pits 

 in the hinge-margin of the left, more conspicuous on the anterior side than behind. 

 Cartilage. — Obliquely inclined towards the posterior end. 

 Surface. — Concentrically striated. 



Necera teres, Jeffreys. 



Section F. 



Teeth. — A short erect lateral tooth on each side, and a small dentiform projection of 

 the hinge-margin in front of the apex in the right valve, and a single tubercular denticle 

 in front of the apex (but no laterals) in the left. 



