274 BIVALVE SHELLS. 



in Talva dextra dentem unicum modo simplicem, modo com- 

 })lexinn pnebente, inter denies duos obliquos in altera valya re- 

 eeptum ; deutihus lateralibns an^ustis, depressis, elongatis, in 

 utraque valva lamelliformibus ; ligamentum breve, angustum, 

 externum ; impressio pallii simplex, postice minime excavata. 



Tellina, Mull. (1/74) Verm. Hist. p. 205. 

 Cardium, Poll (1791), Test. utr. Sicil. i. 65^ 



Mont. (1803) Test. Brit. p. 8(i. 

 Cyclas, Drop. (1801) Tabl. des Moll. p. 106; (1805) Hist, des 

 Moll. p. 131. 



Lamk. (1818) An. s. Vert. v. 559, 

 Pisum, Meff. (1811) Entw. p. 57 (non Linn.). 



Gray (1847), Proc. Zool. Soc. p. 184 ; Ann. S^- Mag. N. H. 

 xi. 34. 

 Pisidium, Pfeiffer, Syst. Anord. p. 120. 



Jenyns (1832), Cambr. Phil. Soc. iv. 300. 



Gray (1840), Turt. Man. ed. 2. p. 285. 



Forbes ^- Hanley (1849), Hist, of Brit. Moll. ii. 130. 

 Galileja, Costa (1839), Corresp. Zool. 



Phil. fl844) Enum. Moll. Sicil. ii. 214. 

 Pera, Leach, 3ISS. (1819) fide Gray, Turt. Man. p. 282 (1840); 



Syn. Moll. Brit. (1852) ed. Gray, p. 291. 

 Euglesa, Leach,MSS. (1819) fide Gray, Turt. Man. p.282 (1840) ; 



Syn. Moll. Brit. (1852) p. 291, ed. Gray. 

 Cordula, Leach (1852), Syn. Moll. Brit. p. 292, ed. Gray. 



1. Synopsis Specierum. 



1. Species Europa^anae, 1-11. 



2. Africans, 12-15. 



3. Americae septentrionalis, 16-23. 



4. Americae meridionalis, 24-30. 



5. Australienses, 31, 32. 



6. Species dubia;, 33-36. 



1 . Species Europceana. 



1. Pisum amnicum. B.J\I. 



P. testa subovato-trigona, inajquilaterali, ventricosa, eleganter 

 striato-costulata, oinereo-luteola, aliquantispcr nigricante zo- 

 nata ; umbonibus parvis, obtiisis, la'viusculis ; dentibus cardi- 

 nalibus in angulum acutum dispositis ; dentibus lateralibus 



1 



