As one of the studies of human posture, the author noticed abnormal muscle tones of cerebral palsy children and measurements were conducted on levels of acceleration of muscle tones in the relaxed posture. Ten types of chairs with different seat tilts and back rest inclinations were chosen and changes in muscle contraction were mentioned electromyographically. Nine subjects all severely involved cerebral palsy children.
Angle of each type of chair is as follows: A type: Seat at an angle of 10 degrees to the horizontal line and back rest at a level of 5 degrees from vertical line to the front. B type: Seat at an angle of 15 degrees to the horizontal line and back rest at a level of 10 degrees from vertical line to the back. C type: Seat at an angle of 10 degrees to the horizontal line and back rest at level of 10 degrees from vertical line to the back. D type: Seat at an angle of 5 degrees to the horizontal line and back rest at a level of 10 degrees from vertical line to the back. E type: Seat is same degree with horizontal line and back rest at a level of 10 degrees from vertical line to the back. F type: Seat at an angle of 15 degrees to the horizontal line and back rest at level of 20 degrees from vertical line to the back. G type: Seat at an angle of 10 degrees to the horizontal line and back rest at a level of 20 degrees from vertical line to the back. H type: Seat is same degree with horizontal line and back rest at a level of 20 degrees from vertical line to the back. I type: Seat at an angle of 10 degrees to the horizontal line and back rest at a level of 30 degrees from vertical line to the back. J type: Seat at an angle of 10 degrees to the horizontal line and back rest at a level of 40 degrees from vertical line to the back.
As a general tendency of the relationship between EMG level and the ten types of chairs, it was found that EMG decreased as the angle of the relaxation chair increased.
The effects on the EMG level of three factors such as type of chair, sample muscles, and subject were tested by the analysis of variance. The results were as follows:
Factor of type of chair: F=3.984(f₁=8, f₂=64), factor of muscle: F=10.723(f₁=5, f₂=40), and factor of subject: F=21.38 (f₁=8, f₂=320). These values were significant at the 1% level. The EMG level was compared between the above 10 types of chairs and the sum of the EMG levels of different muscles in percentages to that of A type was B type 64%, for C type 50%, for D type 62%, for E type 60%, for F type 42%, for G type 30%, for H type 32%, and for I type 42%. The EMG level in case of G and H types was decreased to about Two- Thirds of that of A.
As for the interaction on the EMG level of the three factors of the variance ratio was computed at 1.38(f₁=40, f₂=320) in the case of chair and subject, at 6.566 (f₁=40, f₂ =320) in the case of those of muscle and subjects.
The level of the latter two cases were significant at the 1% level. However, the interaction of the factors of chair and muscles was not significant. This shows the effect of chair on the EMG level independent from the kind of muscle tested.
Therefore, it can be concluded that the G type was the most adequate one among the 10 types of chair tested from the view point of suppressing involuntary muscular contraction of the patient.

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In order to study the processes developing the variation of physical traits among small human populations based on population genetics, the present investigation was carried out in the Hatomajima population of Yaeyama Islands, Okinawa.
This report is particularly concerned with demographic structure and marriage pattern, or reproductive structure, in Hatomajima hamlet and discussion was made on historical and environmental effects extending over many generations which appear to affect the development of the variation in physical traits in such a small population. The results obtained are as follows:
1) The population pattern shows advancing stages demographically, although it shows marked decrease since about 1950.
2) Gene flow seems to be very low, since endogamy rate is very high.
3) Traditionally, the tendency of avoiding the 1st cousin marriage is seen and this seems to have played a role in the effect to prevent homogeneity of physical traits in the population.
4) The average effective size of the population for the last five generations is about 50 to 60, which is rather small in comparison with other isolated populations.
5) The fluctuation of the gene frequencies found in the Hatomajima population is presumably due to the random genetic drift brought from the separation from Kuroshima population about 200 years ago.

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In order to know the physical features of the mandibles of the Chubu Japanese, 68 of male and 44 female bones were measured and compared with those of the other Japanese groups, Korean and Sakhalin Ainu. The mandible of the Chubu Japanese, in males, is characterized by low values in bicondylar breadth, frontal bimental breadth, body length, breadth length index, ramus height, ramus breadth, minimum ramus breadth, notch breadth and notch height, and by high values in body height, body thikcness, robustness index, ramus index and notch index. Biological distance by C²H using four male measurements indicate that the Kinai Japanese is the nearest to the Chûbu Japanese, then followed by the Kanto Japanese (Morita), Tohoku Japanese, Kanto Japanese (Mitsuhashi), Hokuriku Japanese, Northwest Kyushu Japanese, Middle Kyushu Japanese, Korean and Sakhalin Ainu.

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At the Koshima Islet, Miyazaki Prefecture, the social relations of adolescent males were studied by means of the individual tracing method for about 140 days between May 1974 and March 1975. Especially the social relations of males (6-9 years old) which had left the troop and those of males (5 years old) which had been staying in the troop were compared. The affinitive relations among adolescent males, such as grooming, following and sitting near-by or feeding on the same tree, were analyzed. The antagonistic relations among males (6-9 years old only), avoidance and agonistic interactions, were analyzed. In breeding season these interactions increased two or three times as frequently as those in non-breeding season. In the affinitive relations except following interaction the rate of consanguinities observed in the interactions decreased in breeding season in the case of when the partners were females and juveniles. While in the antagonistic relations, they decreased in breeding season when the opponents were males. Adolescent males over six years old preferred as the affinitive partner males of the same generation, females of the same generation and mothers, while they avoided strongly troop males (full adult) and adult females out of the same generation. They had agonistic interactions most frequently with the juveniles throughout the year, and only in breeding season their interactions with the troop males and adult males outside troop were frequently observed.
Five-years-old males occupied the significant stage in the developmental process in the adolescence. In non-breeding season they had affinitive relations mainly with troop members, especially their close relatives, but in breeding season they had many affinitive relations with adolescent males, especially elder brothers, outside troop. They were actually in the critical point socially where they were ready to secede from their own troop. It can be concluded that males secede from their own troop at the developmental stage from five to six years old in Koshima troop. The affinitive relations between adolescent males outside troop and the females of the same generations were conspicuous. The male-female bond in the same generation has the great significance not only as the basis on which the consort-pair will arise, but as the social channel through which males outside troop get tolerated by the troop members in breeding season. The male-bonds among adolescent males outside troop are based on three kinds of relations; i. e. the combination between brothers, the following relation between older dominant male and younger male and the grooming relation between the individuals of the same age. The author classified the social positions of males outside troop into three main types; marginal males, semi-solitary males and solitary males, and two transitional types, based on the dual criteria as to whether they have male-bonds and whether they have stable affinitive relations to troop members. These social positions are flexible in adolescent males, but they are supposed to be more rigid in full adult males.

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Shamanistic rosaries were found out at a dilapidated temple, Yamagata Prefecture. They were used by the miko, Japanese mediums, belonging to this temple, from the times of Edo to Mei ji era (about 100 to 200 years ago).
To the rosaries were tied the rostrum parts of jawbones, fangs, nails, horns, marine shells and others. As a result of taxonomical examination, these materials were identified to be those of the bear (Ursus thibetanus japonicus), the dog (Canis familiaris), the fox (Vulpes vulpes japonica), the wild boar (Sus leucomystax leucomystax), the deer (Cervus nippon nippon) and the antelope (Capricornis crispus crispus).
According to the traditional saying, jawbones of Japanese wolves (Canis lupus hodophilax) completely exterminated in this country had been used as accessories of the rosaries in those days. No remains of wolves, however, were included among them, which proved to be the bones of dogs.
The people of mountain villages then believed that a bear and a wolf were sanctified and occult animals, and their remains had been used as a charm to ward off accidents and diseases.
Using these rosaries, the mediums had practiced divination or had exorcized evil spirits from the patients.

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