NATURAL SCIENCES OF PHILADELPHIA. 91 



Genus CRYPTODON, Turton. 

 Brit. Bivalves, 181. 1822. 



Thyafira, Leach, Jeffreys, Mai. et Conch. Mag. ii. 42. 1829. 

 Axinus, J. Sowerb} r , Mineral Conch, t. 314. 1823. 

 Ptychina, Phil. Moll. Sicil. 15. 1836. 

 Clausina, Jeffreys, Ann. & Mag. Nat. Hist. xx. 18. 1847. 



1. C. Croulinensis, Jeffreys, Ann. & Mag. N. H. xx. 19. 1847. 



Ibid. 3dser.ii. 122,t.5,f.2. 



Skye and Shetland Islands. 



2. C. ferruginosus, Forbes & Hanley, Brit. Moll. ii. 60, t. 34, f. 1. 



1853. Reeve, Icon. Lucina, sp. 63. 1850. 

 Kellia abyssicola, Forbes, J^gean Invert. 192. 



Mediterranean to England. 



3. C flexuosus, Mont. Test. Brit. 72 (Tellina). 1803. Reeve, 



Icon. Lucina, sp. 62. 1850. 

 Axinus angulatus, Nyst. (not Sowb.) Coq. Foss. Belg. 141, t. 



6, f. 13. 

 Venus sinuosa, Donov. Brit. Shells ii. t. 42, f. 2. 

 Lucina sinuata, Lam. Anim. s. Vert. v. 543. 1818. 

 Cryptodon bisinuatus, S. Wood, Crag. Moll. 

 Ptychina biplicata, Phil. Moll. Sicil. i. 15, t. 2, f. 4. 1 836. 



European Seas. 



4. C. Gouldi, Phil. Zeit. fur Malak. 74. 1845. Gould, Invert. 



Mass. 2d edit. 100, f. 406. 1870. 

 Lucina jlexuosa, Gould (not Mont.) Invert. Mass. 1st edit. 



71,f.52. 1841. 

 Thyasira Gouldi, Stimpson, Shells. N. Eng. 17. 1851. 



Massachusetts Connecticut. 



5. C. Japonicus, Adams, Ann. & Mag. Nat. Hist. ix. 227. 1862. 



N. Japan.. 



6. C. Manchuric us, Adams, Ibid. 227. 1862. 



Manchuria. 



N. Japan.. 



N. Japan. 

 9. C. polygonus, Gould, Bost. Proc. viii. 35. 1861. 



Cape Good Hope 



7. C. oblongus, Adams, Ibid. 227. 1862. 



8. C. plicatus, Adams, Ibid. 227. 1862. 



1872.] 



