periodic collection of shallow water stony corals in Puerto Rican waters has yielded thirty eight species which are briefly described. All species can be found on the reefs at La Parguera. At La Parguera. two lines of barrier type reefs lie offshore and parallel to the shore. Patch reefs are found close to shore; most of the species are found near the east ends of the liner reefs in the open back reef waters. Off the northeastern tip of Puerto Rico, a line of small cays have well developed fringing reefs on their northeast sides and patch reefs on their southwest sides. Incomplete collecting in this area has yielded twenty species.