Food habits of sika (Cervus nippon) were studied in Fudakake, Tanzawa Mountains, Kanagawa Prefecture from 1972 to 1975. This area was situated from 370 to 870m in elevation. Eaten plants by sika, 53 families, 80 genera and 106 species were recorded; 72 species of them were trees and shrubs, and 34 species were forbs and grasses. Few plant species, eaten all the year round, were observed. Rather, highly utilized plants, wide-spread and dominant species in this area, successively appeared every season. In winter intensive utilization of sasa (Sasa purpurascence) was exactly effective for sika survival through the critical season of winter when most food plants were unavailable. Parts eaten varied widely with the season and the plant species; especially from late autumn to early spring, barks of a few species, such as Clero-dendrum trichotomum, Aralia elata and Zanthoxylum piperitum, were intensively taken. Since the winter of 1973/1974, new food-taking behaviors, such as“branch breaking”and“culm breaking”, have conspicuously occurred. Simultaneously, not a few plants, which had been utilized at low level or not, became to be taken conspicuously. Those trends were seemingly dependent on sika density and plant succession in the study area.

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Variations, age, sexual, or altitudinal, of Soriculus caudatus, S. baileyi, S. nigrescens, Mus cervicolor, Rattus fluvescens, R. niviventer, and R. nitidus from central Nepal were studied, and taxonomic reviews were made. Two subspecies with allopatric distributions were recognized in S. caudatus, and M. cervicolor from central Nepal, respectively. Additonal diagnostic characters of R. fluvescens and R. niviventer were given. New collecting data on S. baileyi and R. nitidus were recorded.

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To be able to reproduce the vole (Microtus montebelli) intentionally, the authors observed litter sizes and vaginal smears of female voles under the different social conditions (isolated, adjacent to a male, lived in a same cage with a male) . 1) There was little influence of the inbreeding (4 generations) and the seasons on litter sizes. Therefore, it seemed that the vole was able to reproduce throughout the year under the room condition (20-25°C) . 2) From the presence of cornified cells in the smears at copulation and with PMS treatment, these cells seemed to be an index of estrous in the female vole. 3) In the isolated feeding, leucocytes and nucleated cells were predominantly observed in the smears. Regardless of the presence of these cells, females showing a recurrent appearance of cornified cells were found in half the number (5/10 heads) . When females were lived in a same cage with males (1: 1), the recurrent females showed the same appearence rate as that of isolated feeding (13/24 heads) . Thus, the vaginal smear in the vole did not show a definite pattern by reason of individual difference.

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The social organization and habitat use of Japanese serow (Capri-cornis crispus) were studied in Kasabori, Niigata Prefecture from July 1970 to October 1974. Through the observation of 17 identifiable serows, 4 social units were classified. The pair, consisting of a male and a female, was formed from late autumn to early winter and maintained till parturition in late May and early June of the next year. The family, consisting of a pair and its young, appeared after parturition and was maintained till early autumn when the male left. Then, the mother-child group appeared, and lasted till the next summer. Members of those units did not necessarily act together. In a family and a pair, a male took a role as a leader. The solitary was also observed. Although several serows moved in or out of the study area in early summer and autumn, they each stayed in a certain area when their social bonds were maintained. Home range sizes were also calculated; they apparently enlarged as members were added. Vegetation communities, found on thirteen home ranges, were oak shrubbery, Japanese white pine forest, grassland and rocky ground; the first and the second were essential habitats. Since chases after intruders and signpost behavior were observed, the possibility exists that serows are territorial.

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Mensural differences of the external characters and the skulls between the fresh and the formalin-preserved specimens were studied in Bent-winged bats, Miniopterus schreibersi. These differences were compared within each age group.
In all of the skull characters examined as well as in the other external ones except forearm length and hind foot length, the f ormalin-preserved specimens were smaller than the fresh ones as the result of the formalin preservation. The above-mentioned tendency was conspicuous especially in the dimensions of skull characters examined.
In the external characters, an increase in size according to age was not observed. But in all other characters of skull apart from mastoid width, brain case width and lower tooth length, variations with age were suggested to exist, granting the above tendency was not conspicuous.

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The authors had an oppotunity to observe a fresh nest containing four youngs of the Ryukyu wild boar, Sus riukiuanus KURODA, 1924, on October 23th, 1975, at Iriomote Island, Okinawa Prif., Japan. The nest was found in grassland of the tall miscanthus, Miscauthus floridulus, at the foot of Mt. Nakama in the east of the island. It was made of many stems and blades of these grass mowed by their mother pig. The external form was similar to the large muskrat mound, 60cm in height, 1.8m in diameter. The mound contained a main entrance, an estimated emergency exit and a nest chamber. The main entrance was measured 30×30cm in height and width, and seemed to be used generally by the family. The other one was about 7cm in width and was estimated to be an emergency exit. The nest chamber was about 35 cm in height and 65 cm in diameter, and no bedding was found in it.
The young mother pig was dead outside of the nest near the entrance. The youngs were found in the nest silently, but when we approached the nest they ran away through the small exit of the mound, not the main entrance.

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[in Japanese]

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