Niviventer bukit (BONHOTE, 1903) from Thailand was compared with N. fulvescens (GRAY, 1847) from Nepal and the former was regarded as a subspecies of the latter, N. fulvescens bukit, retaining larger body and skull, smaller tail ratio, smaller relative size of bulla, larger relative zygomatic width, and larger relative depth of braincase. N. rapit orbus RoBINsoN & KLoss, 1914, in Thailand was a synonym of N. fulvescens bukit. Taxonomic relationships among rats of Niviventer group in Thailand were discussed and certain problems were pointed out.

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Small mammal fauna was studied in an agricultural land at Nishi-obihiro, the Tokachi District, Hokkaido in 1982. Clethrionomys rufocanus bedfordiae was dominant in open areas, especially in bogs dominated by sedges. Apodemus speciosus ainu occurred in the natural deciduous wood, while Apodemus peninsulae giliacus occupied mainly man-made habitats such as cultivated fields and shelterbelts away from natural woods. Sorex unguiculatus was common in the study area, whereas Sorex caecutiens saevus was few in numbers. Other species observed included Sciurus vulgaris orientis and Tamias sibiricus lineatus.

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Measurements and the coefficients of variability of classificatory characters on seven male, two female and three sex-unknown adult specimens and two male and female young specimens (Table 1) of the Bonin flying fox, Pteropus pselaphon, preserved in the British Museum (N. H.) (BM), US National Museum (USNM), Forsch-ungsinstitut Senckenberg (SencM) and Rijksmuseum van Natuurlijke Historie, Leiden (RML) were shown (Table 2) and compared with those of the preceding studies.
The coefficients of variability of the lengths of upper tooth row (i-m³) and (c-m³), the width of brain-case and the lengths of lower tooth row (i-m₃) and (c-m₃) were below 2.5, and in the post-orbital width the coefficient of variability was especially large, 8.35. The length of upper tooth row (c-m³) and the width across upper molars of the young were about the same size as the adults and the young post-orbital width was significantly (P<0.01) larger than the adult one. The measuring methods of the length of upper tooth row (c-m³), the rostral width and the length of mandible were presumed to be different between Andersen (1912) and the present author. The sizes of the greatest length of skull and the condylobasal length measured by the present author were very smaller than those by the others, and it certainly seems to be caused by the accidental small size of the examined two specimens.

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For the feral house mice (Mus musculus molossinus) which were trapped in fallow fields of grasslands (dominated by Panicum bisulcatum, Setaria viridis or Digitaria adscendens) in Nagoya city (35°03'N, 136°57'E, alt. 5-20 m), the individuals trapped were determined age in days based on lens weight. The mice were trapped in 1979 (Dec.), 1980 (Jan, Feb., Apr., Nov., Dec., ) and 1981 (Jan.-Apr.) . It is shown that the stable age distribution has been maintained for most of the priods, and both sexes have been trapped at random. Therefore life and fertility tables for the post-weaning mice of both sexes can be determined, based on the age distribution of the trapped individuals.
It is estimated that mortality is 0.65, mean expectation of life (ecological longevity) is about 2 months for age group 0 (predicted age; 15-51 days) . Most individuals are thought to die by 8 months after birth, for observed oldest mice (2 females) were 5.5 months old (95% confidence interval; 3.7-8.3 months) .
It is shown that one average female produces 1.20 female youngs for her life, this population is increasing. In spite of their high mortality, their high reproductive rate enables the population to maintain their numbers.
Comparison of the result of this work with that of other areas suggests that mortality and reproductive rate change with areas.
Predators, such as Mustela sibilica coreana play probably little part on high mortality of this population. Other important determinants of mortality are not yet known but it is suggested that the dispersal of an excessive number of individuals is an important factor in affecting their mortality.

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Habitat selection by Sika deer (Cervus nippon) on Kinkazan Island, northeastern Japan, was assessed by direct observation along routes tracked on foot between October 1973 and October 1977. A total of 791 deer groups (3, 237 deer) were found through 121 trackings. Around the shrine, the vegeration was dominated by the Zoysia japonica community, and the deer were tame whose density was highest (ca. 800 deer/km²) . Other deer were wild or semi-wild, and they were more frequently found in openlands than in woodlands. Selection index (S.I.) for each plant community was highest for the Pleioblastus chino community and the Zoysia japonica community, followed by the Miscanthus sinensis community, the Pteridium aguilinum community, and deciduous broad-leaved forests including the Carpinus tschonoskii community and the Fagus crenata community, and lowest for evergreen coniferous forests such as the Abies firma community, the Pinus thunbergii community, the Cryptomeria japonica community and others. Habitat selection by Sika deer on the island is primarily determined by the forage productivity of habitats, though cover requirements and innate socio-behaviorological factors are also important.

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Pair-bond and mother-offspring relationships of Japanese serow (Capricornis crispus) were studied in Kusoudomari, Wakinosawa Village, Aomori Prefecture from March 1976 to December 1982. In most cases home ranges of a male, a female and its youngs were overlapped each other, and the pair-bond and family like group among them were clearly recognizable. Ten dispersals (male 4, female 6) of youngs to establish a new home range were observed during from twenty-four to fifty months after their births. Aggressive behaviour of mother to its offsprings to drive them out of its home range was not recorded. In some cases, severe chases of adult male to two-year-old male in the same family like group which seemed to expell young out the home range were observed. But on the other hand non-agonistic interactions between them were commonly seen in similar circumstances. Dispersals of offspring were thought to be young's voluntary preference primarily. Affinitive relation between a pair were maintained for years regardless of which rutting season (September-November) or non-rutting season (February-June) . Both male and female live a solitary life and they need not any others' help for territory defence, protection against enemies and nursing. Pair-bond and family like group of serows were thought to be a secondary social relationships rather than essential units in their social structure.

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The ages of 320 trapped raccoon dogs, Nyctereutes procyonoides viverrinus TEMMINCK, were determined by the cementum layer method. The animals were collected during the hunting seasons (December to January) of 1974-75 and 1975-76 in the central and north regions of Okayama Prefecture.
Analysis of the age data showed the following results. There was no significant difference in the number of animals between the two sexes. The oldest was age class VI (5.5 years old) in males and age class VIII (7.5 years old) in females. Mean±standard error of ages was 1.18±0.10 years in males and 1.20±0.11 years in females; the difference of mean between the two sexes was not significant statistically. Animals in the first age class were 68.4% of the total. The present sample had lower mean ages and higher percentage of first age calss animals than in the data previously reported by other authors. These differences may be caused by hunting pressure that is specially heavy on the raccoon dog population.

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[in Japanese]

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