PELECYPODA. 33 



Mytillus hamatns Say, Journ. Acad. Nat. Sci. Phila., 1822, ser. 1, 

 vol. 2, p. 265. 



R. I. — Narragansett Bay. 



Conn. — New Haven Harbor (Perkins, 1870). Introduced in 

 the planting of southern oysters in these waters. 



*Modiolus modiolus (Linne). 



Lamarck, Prod. Nouv. Class. Coq., 1799, p. 87. 

 Mytiliis modiolus Linne, Syst. Nat., ed. 12, 1767, vol. 1, p. 1158. 

 " M. Mediterraneo, Norvegico." 

 Modiola modiolus Gould, Inv. Mass., 1870, p. 186, fig. 485. 



Me. to Conn. — Common, from low water to 80 fathoms, 



*Modiolus (Brachydontes) demissus plicatulus (Lamarck). 



Dall, Trans. Wagner Free Inst. Sci., 1898, vol. 3, pt. 4, p. 795. 



Mytilus demissus Dillwyn, Catalogue, 1817, vol. 1, p. 314. 

 " Virginia." 



Modiola plicatula Lamarck, Hist. Nat. Anim. sans Vert., 1819, 

 vol. 6, pt. 1, p. 113. No locality. Gould, Inv. Mass., 1870, p. 

 188, fig. 486. 



Modiola plicahda truncata Davis, Apteryx, 1905, vol. 1, p. 117, 

 pi. 9, fig. D. 



Me. — Casco Bay; mouth of the Kennebec River. 



Mass. — Salem; Revere; Chatham; Woods Hole; Edgartown. 



R. I. — Oakland Beach; Buttonwoods; Wickford. 



Conn. 



*Musculus substriatus (Gray). 



Modiola laevigata var. /S. substriata Gray, Suppl. to Appendix to 

 Parry's Voyage 1819-20, 1824, p. ccxlv. [Northwest Passage.] 



