Many fresh specimens of Coryphella were collected from some local hydrozoan (Tubularia) colonies in Akkeshi Bay in August, 1956. They were again referred to Coryphella athadona Bergh, 1875, which had originally been recorded from the Japan Sea and later from Mutsu Bay, Akkeshi Bay and elsewhere, principally in view of the round foot-corners of the animals. This paper describes the anatomy of these animals and summarizes their specific status.