ABSTRACT
INTRODUCTION Clams belong to a large group of mollusks clas-
sified as Bivalvia. This class consists of at least 7000 species (Quayle and Newkirk, 1989), but only a few are commercially important. This chapter will review seven North American species for which a significant commercial or recreational fishery exists. The taxonomy for these species is presented in Table 1 and landings data in Table 2. The commercially important Manila clam (Tapes philippinarum), an introduced species intensively cultured on the West Coast of the United States, is not included in this discussion of North American species.
