BIVALVE SHELLS. 273 



conspicuo; cardine anp:ustissimo bitlentato, dentibus exiguis, 

 latenilibus parvis, antico [)aulo niajore. 



Sphteriura Nova^ Zelandi;c, Desh. Proc. Zool. Soc. 1854. 



Hab. Nova Zelandia ; Nova Hollandia. 



46. Sph^rium egregium. 



S. testa ventricosa, transversa, oblonga, subaquilaterali, trans- 

 versim tenui-lirata ; apicibus parum elevatis, tumidis ; epider- 

 mide viridi corneo fusco zonata, plerumque Cycl. corneae simili. 



Cyclas egregia, Gould, Proc. Bost. Nat. Hist. Soc. iii. 292 ; 

 United States Explor. Exp. Moll. p. 425. f. 526. 



Hah. In fluvio Hunteriano Novae HollandijE. 



/. Species dubi<s. 



47. C^clas globosa, il/e^rer^e (non D'Orb.),inA. SfJ. B.Villa,Disp. 



Syst. Conch. p. 44. 



Hab. Sangobard (Fi7Za). 



48. Cyclas orbicularis (non C. orbicularia, Roemer), Linsley, Cat. 

 of the Shells of Connecticut, Amer. Journ. xlviii. 276. 



Hab. America septentrionalis ; East Haddam {Linsley). 



49. Cyclas \\xte3i,Zi€gler,inAnt07i,Verz. derConch. p. 14. no. 511. 

 Hab. ? 



50. Cyclas Steinii, Schmidt, Zeitschr.f Malak. no. 8, 1850, p. 1 18. 

 Hab. ? 



51. Cyclas truncata, Linslcy, Amer. Journ. xlviii. 276. 



Hab. America septentrionalis ; Stonington, Stratford et Strat- 

 field {Linsiey). 



Genus 6. PISUM. 



Animal ovato-rotundatura, inicquilaterale, sa^pius turgidum ; 

 pallium simplex, antice inferneque aj)ertum, postice in trachea 

 unica terminatura ; pes lingaiformis, compressus, apice acutus 

 vel subcylindraceus ; labiorum apj^endices brevcs, angustas ; 

 branchia; inaiquales, lata?, transversim oblique striata^, subplicata;, 

 postice intcr se conniventcs. 



Testa miniraa, tenuis, inaequilateralis, ovata vel subrotunda, 

 subglobosa, la^vigata substriatave ; cardine angusto, dentato, 



12** 



