J. P. Smith — Periodic Migrations. 229 



Table showing Living Species common to the West Coast and Japan. 



Barbatia gradata Sowerby — 



Cardium blandum Gould 



Cardium corbis Martyn 



Chlamy do chiton annulatus Pallas. — 



Crepidula grandis Midd 



Cryptochiton Stelleri Midd 



Diplodonta orbella Gould 



Dentalium hexagonum Sowerby 



Haliotis Kamtschatkana Jonas 



Laqueus californicus Koch 



Lascea rubra Montagu _ 



Leptothyra Carpenteri Pillsbry 



Lima orientalis Adams 



Littorina sitkana Philippi 



Lucina borealis Linne 



Macoma edulis Nuttall _. 



Macoma inquinata Gould 



Macoma nasuta Conrad 



Macoma secta Conrad 



Modiola flabellata Gould 



Macron Kelletii A. Adams 



Mopalia muscosa Gould 



Murex foliatus Gmelin 



Mya arenaria Linne 



Mytilus edalis Linne ._ 



Nuonla Cobbeldiae Sowerby 



Natica clausa Broderip 



Panopaia generosa Gould '. 



Pecten caurinus Gould 



Pecten jessoensis Stimson 



Pecten hericeus Gould 



Pecten islandicus Muller 



Placuanomia macroschisma Deshayes 



Purpura crispata Chemnitz 



Purpura lapillus Linne 



Sanguinolaria Nuttalli Conrad 



Saxidomus Nuttalli Conrad 



Siphonalia Kelleti Hinds 



Siliquapatula Dixon _. 



Solen sicarius Gould 



Tapes staminea Conrad . 



Tellina bodegensis Hinds . 



Terebratulina caput-ser^pentis Linne.. 



Tresus Nuttalli Conrad 



Tritonium oregonense Redneld 



Trophon orpheus Gould 



Velutina laevigata Pennant 



Venus Kennerlyi Carpenter _ . 



Japanese Province. 



West American 

 Province. 



Plio- 

 cene. 



Pleis- 

 tocene. 



Living. 



Plio- 

 cene. 



Pleis- 

 tocene. 



Living. 





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1 





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But in lat. 42° N., off Hakodadi, Japan, it is met by the cold 

 current from Bering Sea along the coast of Kamchatka, and 

 from there on the current is merely temperate, being reduced 



