The karyotype of a torrential ranid, Staurois latopalmatus from Sabah, Borneo, is analyzed from gutt epithelium. The karyotype is of ancestral ranid type, 26 chromosomes consisting of sharply disjunct 5 large and 8 small pairs.

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A young female Rana nigromaculata with a supernumerary forelimb was collected in a paddy field. The administration of testosterone to this frog induced the development of the thumb pads on the normal forelimbs as well as on the supernumerary limb. The skeletal structure of the manual region and histological structure of the thumb pads are described. Studies of this kind seem to be effective in solving the mechanism inducing pad development on a specific part of the fingers.

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Egg-laying of the Rana nigromaculata-brevipoda complex was studied in Jimokuji and Kiyosu of Aichi Prefecture (for R. b. brevipoda), Mabi of Okayama Prefecture (for R. b. brevipoda and R. nigromaculata), and Konko of Okayama Prefecture (for R. nigromaculata) by the observation of ovaries. The rice fields of these places were well-drained, and were dried up in early spring. R. nigromaculata was thought to lay eggs even in small streams among dried rice fields. On the other hand, R. b. brevipoda laid eggs in the rice fields filled with water by irrigation. In Jimokuji, R. b. brevipoda began to lay eggs in mid- or late May. Larger females were thought to lay eggs twice. In Kiyosu and Mabi, however, the egg-laying was started in mid-June. The second egg-laying seemed difficult in these places. R. b. brevipoda in Mabi, which is referred to the Okayama brevipoda race of Moriya, showed a development pattern of ovaries similar to that of the Nagoya brevipoda race.

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Time required for larval Onychodactylus japonicus to swallow prey was measured for various prey items differing in type and size under laboratory conditions. Handling time varied markedly from 10 to 1, 640 seconds according to prey type and size. The relationship between handling time and prey size is described for three prey types.

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Temperatures of body (oesophageal) and surrounding environment of 1434 Elaphe quadrivirgata were measured in the fields between May 1958 and October 1969. From these data the following became clear. Body temperature (BT)is 28.7°C on the average, and has a correlation more close to substratum temperature (ST) than to air temperature (AT). Mean BT, 25.4°C in March, gradually increases toward August (31.7°C) and then decreases in December (21.4°C). Monthly mean BTs are almost constant from June (30.7°C) through September (30.7°C), except in August when the mean is slightly higher than in other months. Monthly maximum BTs are similar from April (35.6°C) throughout October (34.4°C). Mean BT of females (29.2°C) is slightly higher than that of males (28.2°C). There is a significant difference in BT between snakes with prey (29.2°C) and without prey (28.6°C) in their stomachs. From the relationship between ST-AT and BT-ST, thermoregulation of snakes is discussed.

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[in Japanese]

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