From February to October, 1981, the heart rate of a Japanese rat snake, Elaphe climacophora, was measured with a clinic electrocardiograph. The ECG electrodes were made of fishhooks and attached subcutaneously. After attachment of leads the snake was put in a box covered with a black curtain and placed in a room without airconditioning. The body temperature was monitored with a thermistor thermometer, and ranged from 0 C in February to 33.5 C in July. Based on 22 data derived from 274 records, the smoothed curve follows the equation of T=-7.263+10.873 ln H (r=0.983) where T equals temperature and H equals heart beats per minute. The logarithmic regression was also proved in some other snakes for the heart rate-temperature relationship.

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Growth and egg-laying of the two Japanese pond frog species, Rana brevipoda and R. nigromaculata, were studied in Tatsuda and Saya of Aichi Prefecture. In R. brevipoda, some fast-growirng females matured in autumn of the year of metamorphosis, and laid eggs after the first hibernation. The large adult females laid eggs twice in the breeding season, which ranged over two months or more. The allocation rate of matter for eggs was estimated to be relatively large. On the other hand, females of R. nigromaculata matured in autumn of the year following metamorphosis. They allocated less matter for eggs, and laid eggs only once in the breeding season, which was much shorter than that of R. brevipoda. Both R. brevipoda and R. nigromaculata began to lay eggs in late April or early May, and no seasonal barrier for crossing was observed between the two species.

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