Abstract
Shijuhachi-numa Pond consists of about 45 pools on rock terrace of the Nagatoro Park, Saitama prefecture. Numeral samples of crustacean plankters were collected from the main 11 ponds with plankton-net of 64μm mesh during the survey from 1989 to 1992. They were referred to 9 copepods and 18 cladocerans including some rare species such as Acanthocyclops vernalis, Rynchotalona rostrata and Chydorus barroisi. Thermocyclops dybowskii was newly added to the carcinological fauna of Japan.
