The seasonal movements of sika (Cervus nippon) were investigated by footprint counts on the south slope of Mt. Nyoho (2, 464m in elevation) in Omote-Nikko, Tochigi Prefecture, between June 1972 and January 1974. This area ranges from 900 to 2, 000m in elevation.
In January, sika moved down to the area below 1, 500m in elevation. In February and March, they were concentrated at 1, 200 and 1, 300m in elevation. It is probable that both were primarily affected by deep snow. In April, as the snow melted, they began to move up again. In May, the downward movement occurred, because they were probably attracted by palatable plants beginning to grow in the lower area. And then they gradually moved up, as the development of plants progressed from the lower area to the higher area. In June, the peak of calving season, they were widely and evenly scattered over the area. Since then the upward gradual movement continued till August. Since none of bucks were observed in summer in the lower area below 1, 600 m in elevation, they probably stayed in the sub-alpine zone in this season. During late August and September, the downward movement was recognized. In November, the abrupt defoliation probably caused them to move up to the ever-green coniferous forest in the sub-alpine zone.

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Twelve dead bodies of Japanese serow, Capricornis crispus crispus, were found during the period from May 1967 to May 1975 in the southern parts of the Japan North Alps, and from their stomach contents, the kinds of eaten plants were identified. The locations of the discovery are 1, 100-2, 000m high above the sea-level, and the times of death were estimated to be autumn (October-November), deep snow season (February-April), and early spring (March-May) .
Autopsy of the 12 bodies disclosed that eaten plants in the stomachs belonged to 7 species of 2 families of needle-leaf evergreen, 7 species of 6 families of deciduous broadleaf tree, 4 species of 1 family of broad-leaf evergreen, and 9 species of 7 families of herbs, totaling 27 species of 16 families (Table 1) .
Tables 2 and 3 give the species and families as classified by the seasons of death. In autumn, 9 species were eaten, and many of them are broad-leaved, only one species being needle-leaved. In the deep snow season, 8 species were eaten, and needle-leaf trees were predominant. In early spring, species of edible plants abruptly increased to 18 species, and the proportion of eaten herbs also increased.
Tables 4 and 5 give of edible plant for Japanese serows, which were confirmed by the traces of being eaten in summer. They were very numerous, and moreover herbs were predominants.
In this way, broad-leaved evergreens in autumn, needle-leaved trees in the deep snow season, and herbs in spring to summer are important food for Japanese serows. In other words, they are fond of fresh green leaves.
As the consequence, the deep-snow season is very difficult for them to live. Complete deforestation of vast mountainous tract makes it inhabitable for them, which would be forced to give damage to the afforestation areas of Japanese cypress. This is a mute resistance by serows to environment devastation. At the same time it is a warning against deteriorating miliew of the human being.
In one case, two pieces of vinyl-like synthetic resinous cloth were discovered.

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Two macerated monozygotic twins associated with two live fraternal twins in a pregnant hyrax are reported. The identical twins had a single, monozonary, infarcted placenta and corresponded to one corpus luteum in the homolateral ovary, whereas the fraternal twins with two placentas had two corpora lutea in the opposite ovary.
The Cape hyrax (Procavia capensis) has been recommended as an animal of potential value for medical research in the study of gastric ulcer (Griner, 1968) . They resemble rodents only superficially but are placed more closely to the Proboscidea in taxonomic position, in a separate Order, the Hyracoidea, because of characteristics of their feet and the large bulge of the anterior maxillary skull, placentation, etc. Most litters of the hyrax at the San Diego Zoo have been born during May and June and the gestational period of the hyrax is estimated to be 7 1/2 months (Griner, 1968) .
THURSBY-PELHAM (1924) pointed out that the hyrax placenta has a zonary form and a certain resemblance to that of the elephant. WISLOCKI and WESTHUYSEN (1940) described the placenta and fetal membranes of Procavia in greater detail and also suggest that the elephant and the manatee exhibit very close structural placental affinities. Placentation is characterized as chorioallantoic, labyrinthine and of the hemochorial type (WISLOCKI and WESTHUYSEN, 1940) .
The usual litter size of hyrax varies from one to six, the average being three (GRINER, 1968) . The distribution of the embryos in the uterus and their relationship to the corpora lutea in the ovaries of pregnant Procavia has been described as usually homolateral (WISLOCKI and WESTHUYSEN, 1940), that is to say, the number of corpora lutea in one ovary usually corresponds to the number of embryos of the uterine horn on the same side. Exceptions, however, were recorded and“internal migration”is a suggested explanation. No information concerning the occurrence of identical twins in the hyrax has been recorded.
This report describes the uterus of a pregnant hyrax in which one horn contained fraternal twins with two independent placentas, whereas the opposite horn held presumably monozygotic twin fetus papyracei with a single placenta. There were two corpore lutea in the first ovary and only one in the second.

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The Japanese otter has been protected by game law since 1928, but now it is on the brink of extinction from Japan. In the previous five years from 1923 to 1927, 325 individuals were lawfully captured as shown in Table 1.
In this paper, unknown and additional records of the Japanese otter are given from Fukushima, Ibaragi, Saitama, Tochigi, Gunma (Figs. 1-3) and Wakayama (Fig. 4) with a few suggestive informations of survival in Honshu. On the basis of the literature hitherto known and a new additional example from Gunma, the author think that the litter-size of the Japanese otter in a wild state is usually 2.

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The male and female karyotypes of Cricetulus triton nestor THOMAS, 1907 (greater long-tailed hamster) obtained from Wontong-myun, Rinje-kun, Kangwon-do (northeastern part of Korea) are analyzed by using conventional, G-band and C-band method.
The diploid chromosome number is 28 in the bone marrow preparation. Eleven autosome pairs are a graded series of acrocentric, and remaining 2 pairs are metacentric chromosomes. The X chromosome is large size subtelocentric and the Y chromosome is medium size metacentric.
The opinion of ELLERMAN and MORRISON-SCOTT (1951) that Tscherskia albipes is a synonym of Cricetulus triton nestor could be supported by comparing the present data and the previously reported ones (VORONTSOV and RADJABLI, 1969) .

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From December, 1972, to November, 1973, wood mice, Apodemus argenteus, were captured monthly by snap traps in the mountain zone (1000m above sea level) on Tobira Pass in Honshu. The total number of captured wood mice was 108. The hearts were removed and carefully separated to right ventricular wall and left ventricular wall (including interventricular septum) . Then they were dried and weighed. Measurements were analyzed in relation to seasonal temperature changes in the habitat. Seasonal changes in ventricular weights were observed in wood mice with significantly heavier total ventricular weights, left ventricular weights and right ventricular weights occurring during late autumn and winter than in summer. These changes are considered to be one aspect of metabolic acclimation to seasonal temperature changes, especially to decreasing temperature in late autumn and winter.

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In recent years, colonies of nutria have established in wide range in Okayama Pref.. Some damages have occurred on the rice crop by eating the shoot in this prefecrure.
This report deals with histrical process of the introduction and the dispersal of nutria, based on records of annual kill and informations from legal game watchers through a questionnaire.
This animals have been bred for their valuable pelts. At least 48 fur farms existed widely in Okayama Pref. from 1938 to about 1955. Because of decreasing in a demand of pelt, these farms appear to have discontinued. Then, a large number of nutrias were released. Most of them succeeded in establishing their colonies with low densities in the network of Yoshii- and Asahi-river. But they did not attract attention. The animals, settling in the reclaimed land of Kojima area, have been increasing in numbers. This area is favored condition for the animals. This population has been expanding their range gradually in two directions: to the north along Yoshii- and Asahi-river, and to the west along Oda-river.

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This study was aimed to examine surviving populations of field mice in small groves isolated by turning the land into housing lots.
Study areas were selected on the hills around Mt. Takatori (139m), near Yokouka city. Here, new housing is rapidly progressing splitting original wooded hills into isolated groves. (Fig. 1)
For one survey, 60 snap-traps were set through 3 nights, and this was repeated 7 times during Sept. Oct. and Nov. in 1973. (Table 2)
At Oppama and Taura study areas of less than 10 hectare groves, no mice were collected. At those small isolated groves the mice population had apparently died out during winter, since judging by other field studies, small isolated population of Apodemus would not be able to survive the winter if the area is less than 7 hectare.
Three times trappings of mice at Jimmuji showed that in this district most of Apodernus speciosus were living in damp places or swamps and were not evenly distributed but localized at certain places.
By microscope analysis of stomach contents of A. speciosus many bacae and arthropods (river crabs and insects) were found, but there was no trace of acorn. (Table 3)

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The estimation of the population size of wild Norway rat (Rattus norvegicus) was carried out in Gotenba City, from 11 to 14, September, 1974. In the present test, number of rats inhabited in the yard was estimated 203 individuals by ZIPPIN's method. The body weight of 52% of individuals of the total number was less than 70 grams. The fertility of the rats collected may be held assumed during July and August in the summer.

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Five pregnant females of Pipistrellus abramus (TEMMINCK) were collected at Zentsuji City in Kagawa Pref., June 9, 1973.
The parturition and external, cranial and dental characters of embryos and litters were studied. The results can be summarised as follows:
1. The period of parturition was June, 9-13.
2. The embryo-size varies from 2 to 4 with an average 3.0.
3. There was a considerable difference in absolute size of the external characters between embryos and litters. But, their proportions to the size of adults were nearly same between them.
4. The skull in embryos and litters was in a stage more advanced than that of the external characters.
5. The sutura of occipitals in embryos or litters attains to perfection more rapidly than that of frontals.
6. The order of eruption in milk teeth was as follows; first: there are two upper and two lower incisors and one canine in each side of the jaw; second: one premolar erupts both on upper and lower jaw; third: one incisor on lower jaw; fourth: one premolar on lower jaw; and fifth: one premolar on upper jaw.
7. The each crown of dig, di3, dc, dpml, DI1 and DI2 was divided into three lobes. That of DC was L-shaped and that of dpm2, DPM1 and DPM2 was wedge-shaped. The crown of dil with two lobes was observed.

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Distribution, fighting behavior, ecological niche and some breeding habits of Myotis pruinosus YOSHIYUKI, 1971 are noted. Three pregnant females exam-ined by the author are shown in following table.

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