Ecological study of the feral cat (Fells catus LINN.) was conducted in a small island, Ainoshima, Fukuoka Prefecture. Radio-tracking and direct observation were employed to investigate the daily activity. Cats spent larger part of a day in resting except for rutting male. They showed high activity at dusk and dawn, and this pattern was fixed both among individuals and through the year. Highly active time in a day shifted seasonally. Cats showed a nocturnal habit in summer and a more diurnal habit in winter. This fluctuation is closely related to air temperature; as the air temperature became higher, active time shifted from daytime to nighttime. The rain also influenced upon the activity of them. Mating activity also changed seasonally; mating season was monomodal from January to September in this island. These characteristics of the activity of the feral cat is discussed with reference to comparison with some other carnivorous mammals.

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Studied on the growth of young and parental care of the raccoon dog, Nyctereutes procyonoides viverrinus TEMMINCK, in captivity.
Offspring weaned at 30 days old and developed their behaviour from 30 to 80 days old under parental care. Body weights of offspring reached adult size at 150 days old. They lived relatively independent at this time.
The male took part of pup caring up to 80 days from delivery, but the female played a greater part of it.

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Classifications of the Japanese bats (Table 1) contained within the socalled Siebold's specimens preserved in the Rijksmuseum van Natuurlijke Historie, Leiden were reexamined. On these specimens differences of classification, sex and adult or young between the descriptions in the catalogues of JENTINK (1887) and (1888) and the observations of the present author were summarized in Table 1, and the preserved conditions of these specimens were also added in this table. The main differences were as follows : The specimens of number 15 and 16, and also number 22 and 23 are distinct individuals respectively against JENTINK (1887) and (1888) . The number 26 labeled as “d” but unknown in JENTINK (1886), seems to be the skull of skin specimen of the number 25. The bat of number 21 is Nyctalus noctula from Europe, not N. lasiopterus from Japan. The number 22 is Nyctalus leisleri from Europe, not Pipistrellus abramus from Japan. The specimens of number 35 and 36 are Pipistrellus abramus from Japan, not P. pipistrellus from Japan.

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Reproduction status was compared between large Japanese field mouse (Apodemus specious) and house mouse (Mus musculus molossinus), which were predominant on fallow fields in Nagoya City (35°03'N, 135°57'E, alt. 5 to 20 m) . The main breeding season in the field mice was spring (March to May) and fall (September to December) . Although the house mice were not trapped on May to October, it may be considered that they bred on October to May to say the least, and were able to breed throughout the year. The house mice had a significantly larger mean number of normal embryos per litter than the field mice (6.0 versus 4.6) . The field mice had the significantly smaller number of embryos in spring than in fall (3.2 versus 5.6), whereas the house mice did not show significantly differences between the spring and winter ones (5.3 versus 6.2) . It may be concluded that the house mice, as compared to the field mice, have the higher reproductive capacity, in the respects of their longer breeding season and larger embryo sizes.

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Territorial behavior of the Japanese serow (Capricornis crispus) was studied in Kusoudomari, Wakinosawa Village, Aomori Prefecture, from March 1976 to December 1982. Inhabited ranges of adult males and females were overlapped in many cases, and males expelled other males, and females did the same, all the year around. Severe chase of a serow against an intruder was often observed. This behavior has been seen as a male against a male, a female against a female, an adult male against a male yearling, and an adult female against a two year old female in cases when they encountered with others in their own home range overlapped with others. This sort of chase has not been seen between an adult male and a female, an adult male and a female yearling, and an adult female and a male yearling if they en-countered in similar situations. Consequently it seems that territorial exclusion only appears against other serow of identical sex. Serows' territory exists bascally for protecting their own feeding areas, and for keeping stable pair-bond. They do not show tendency of having a united territory of family like groups or pairs. Territorial protection and dispersal of youngs away from it might be for stability of serow's population density.

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Total 182 wild wood mice, Apodemus speciosus, were collected with snap traps during the period from August 1981 to January 1983 at Miasa village (alt. 830 m) in Nagano Prefecture. Their hearts were dissected and separated into the right (RVW) and the left (LVW) ventricular walls. Ratio of the right ventricular weight against the total ventricular weight (RVW/TVW) was obtained and used as an index of the right ventricular hypertrophy. The values seemed to be related to the seasonal changes of air temperature in the animal habitat.
The results are as follows : TVW, LVW, RVW and RVW/TVW of the wood mice collected in late autumn and winter were apparently greater than those collected in summer. From this study, it became clear that the cause of hypertrophy in cold seasons was the ventricular hypertrophy in both sides, particularly, hypertrophy was more progressed in the right ventricles.
Those changes of weight are considered to be a physical aspect caused by the metabolic adaptation to the seasonal temperature changes, especially to the low temperature in late autumn and winter.

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