抄録
Age of sexual maturation and clutch frequency of Rana porosa porosa were estimated from the seasonal changes of SVL distribution, ovary weight, and ovum size distribution. SVL of the smallest adult female was 52mm in Toyono of Nagano Prefecture, and 49mm in Ebina of Kanagawa Prefecture. A few females in Ebina laid eggs after their first hibernation. In Toyono, where the rice fields were irrigated in late May, at least some adult females laid eggs three times in a breeding season. The egg-laying pattern of R. porosa porosa was essentially similar to that of R. porosa brevipoda, though the former prepared second and third clutches more rapidly.
