A table for the normal stages of the development of the Japanese lungless salamander, Onychodactylus japonicus, is presented. Adult males and females, collected in Hinoémata, Fukushima Prefecture, in the breeding season, were injected with frog pituitaries, and oviposition was induced. The number of eggs laid by one female was 11 on the average. The eggs are pale yellow in color and ca. 5mm in diameter. The temperature of the water in which the materials were kept was maintained at 10±1°C. The progress of development is remarkably slow. Under the present conditions, the embryos hatched at the age of 142 days on the average. In contrast to most amphibian species, the 3rd cleavage is meridional and the 4th one is latitudinal. Under field conditions, the period of larval life is fully 2 years, and the body size of metamorphosing larvae is 7-10cm in total length. The process of development from fertilization till the completion of metamorphosis is divided into 72 stages. External characteristics in each stage are described in tabular form, and illustrated with sketches.

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I obtained a group of 5 Japanese pit vipers, Agkistrodon blomhoffi blomhoffi (2 males and 3 females), from a reptile dealer in New Jersey in June 1963 and kept them in captivity. One female bred annually from 1964 to 1967, a second female bred once in 1966, and the third female bred in 1966 and 1967. Of the 7 broods born in captivity, the number of young in each litter varied from 3 to 12 with a mean of 7.0. The conditions of light and temperature in the cages were as follows: in winter, 8 hours of light, with a temperature of 19-21°C during the day and 13-15°C at night; in summer, 16 hours of light, with a temperature variation of from 21 to 29°C; the light and temperature were gradually increased during the spring and decreased during the fall.

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The existence of cyclic fluctuation in the number of habu, Trimeresurus flavoviridis, caught on Amami Oshima was examined with a computor. The spectral analysis represented statistically periodical properties of a time series. Regarding the yearly fluctuationof the number of habu caught in the period from 1954 through 1977 as a realization of a stationary time series, we tried to obtain estimates of the spectral density by two methods: (1) Blackman and Tukey's estimate, and (2) fitting to an autoregressive model. Through the latter method, we found peaks appearing at about 4 and 8 year cycles. The existence of these cycles was ascertained by simulation, notwithstanding our limited data of only 24 observations. It appears that a change of sugarcane yield at a given time negatively correlates with the number of captured of habu 7 years later.

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