137 



Family Peiricolidce. 



Petricola PHOLADiFORMis, Lamarck. 



Petricola pholadijormis, Lamarck (1818) ; and Say (1834). 



Petricola fornicata, Say (1822). 



Petricola dactylus, Say (1834) ; and Gould (1841 and 1870). 



St. Mary's Bay, N.S. (Verkruzen) ; Sable Island, rare (Willis); south 

 coast of Prince Edward Island, burrowing in reefs of red sandstone and 

 shale (Sir J. W. Dawson, and F. Bain) ; Shediac Bay, and elsewhere in 

 Northumberland Strait (Whiteaves). 



Family Diplodoniidos 



Cryptodon Gouldii, Phillippi. 



iMcina fiexuosa, Gould (1841) ; non Montagu, sp. 



Lucina Oouldii, I'hilippi (1845). 



Thyasira Gouldii, Stimpson (1851). 



Cryptodon Gouldii, H. and A. Adams (1858) ; et auct. 



Widely but apparently very sparingly distributed through the whole 

 region, from the Bay of Fundy, Atlantic coast of Nova Scotia and Gulf and 

 mouth of the River St. Lawrence, to Labrador and Greenland, at depths of 

 about 10 to 313 fathoms. 



According to Sir J. W. Dawson, shells of this species are rare in the Leda 

 clay pf Montreal. 



Cryptodon obesus, Yerrill. 



1872. Amer. Journ. Sc. and Arts, Third Series, vol. in., p. 287. 



Off Nova Scotia, Verrill ; who says also that he has detected one specimen 

 of this species among the shells, etc., dredged by Packard in 1864 on the 

 Labrador coast. 



Cryptodon planus, Verrill and Bush. 



. 1898. Proc. U.S. Nat. Mus., vol. xx., p. 788. 



"Found in 8 to 100 fathoms, north of Cape Cod, in the Gulf of Maine, 

 Casco Bay, Bay of Fundy and Halifax Hnrbour, 1872, 1885 " (Verrill and 

 Bush). 



