328 Mighels' Catalogue of 



of opinion this is the utmost northern linait of the species. It 

 however occurs in a fossil state, of a large size, in a post-ter- 

 tiary bed, on the coast of Cumberland, ten or twelve miles 

 east of Portland. 



I am at a loss to conceive how any living species of oyster 

 of the United States, should have been confounded with Ostrea 

 eduUs, Lin. I say living species, because I have received 

 fossil specimens of O. edulis, from the banks of the Potomac, 

 near Washington, which perfectly accord with those of Europe, 

 but differ widely from all our living species. 



Captain Walden has presented me with the lower valve of 

 an oyster, (or Efheria) which he dredged somewhere east of 

 Portland, which I cannot make out. It certainly cannot be 

 confounded with the species found at the Green Islands. It is 

 four inches long, one inch wide, and appears to have been 

 fixed upon the convex surface of a stone of soft texture, per- 

 haps limestone. 



Genus Anomia. Lam. 



A. ephippium, Lister. Lin. Distorted, dwarfish speci- 

 mens of this species are occasionally found on our shores. 

 Whether it has colonized our stormy coast from choice or acci- 

 dent, I am unable to say ; one thing is clear, however, what- 

 ever its motive has been, that it has found an uncongenial 

 climate. 



A. aculeata, Gmelin. Shell pelagic. This species is often 

 found attached to the roots of marine plants, pebbles and 

 other shells, which are thrown ashore by storms. I have, also, 

 often found it fastened to the backs and claws of the larger 

 Crustacea. 



Besides these, there are several others found in the State, 

 which I doubt not are distinct species ; not, however, being 

 able to ascertain whether they have been described, or indeed 

 to separate them definitely, I have deemed it best to pass by 

 them. They all occur as far north and east as Passamaquoddy 

 Bay. 



