MARINE PROVINCES. 16T 



The pi'esence of the same genera gives a veiy similar aspect to 

 the West American and Japonic faunas ; especially the develop- 

 ment of special forms, such as Saxidomus, Siphonalia, Chloros- 

 toma, etc. A few circumpolar species occur in Japan, several of 

 them being common to the Boreal province on the Atlantic coast 

 of the United States, and to Great Britain. Among them are : 



Saxicava arctica. Lassea rubra. Cardita borealis. 



Mya arenaria. Crenella faha. Puncturella Noachina. 



Modiola modiolus. Nucula tenuis. 



To complete the story of the intermixture of species, the 

 following Mediterranean forms are also encountered : 



Triton oleariua. Turbo sanguineus (var.). 



Lima squamosa. Lithodomus caudigerus. 



XI. Aleutian Province. 



The species of the Boreal province are well represented on the 

 nofthern coasts of the Pacific ; in addition to which there are 

 manj^ Californian and Japanese forms. 



The influence of the Asiatic coast-current is shown in the 

 presence of two species of Haliotis. whilst affinity with the fauna 

 of W. America is strongly indicated \iy the occurrence of Patella 

 (Scurria), three species of Crepidula, two of Fissurella, and 

 species of Bullia,Placumonia, Cardita, Saxidomus, and Petricola, 

 which are more abundant, and range farther north than their 

 allies in the Atlantic. 



The proportion of peculiar species in this Province is already 

 surprisingly small, and is becoming smaller: it has but little 

 claim to rank as a distinct fauna. 



Provinces on the Western Coast of America. 



The mollusca of the Western coast of America are equally 

 distinct from those of the Atlantic and those inhabiting the 

 central parts of the Pacific, but by no means so peculiar as 

 Woodward supposed. I quote him to show how prepossessions 

 will mislead naturalists : 



" Mr. Darwin states in his Journal (p. 391) that ' not one single 

 sea-shell is known to be common to the Islands of the Pacific 

 and to the west coast of America,' and he adds that ' after the 

 comparison by Messrs. Cuming and Hinds of about 2000 shells 

 from the Eastern and Western coasts of America, only one 

 single shell was found in common, namely the Purpura patula, 

 which inhabits the West Indies, the coast of Panama, and the 

 Gralapagos.' Even this single identification has since been 

 doubted. Mr. Cuming, who resided many years at Valparaiso, 

 did not discover any West India specimens on that coast, and 



