This article reviews several studies on sexing bones and teeth by discriminant function method which particularly concern with the modern Japanese samples.
Since PONS (1955) applied this method on human femur and sternum, investigators in the fields of physical anthropology and forensic medicine have come to recognize its usefulness for sexing, and a good number of studies have been undertaken.
Using Japanese samples, HANIHARA first reported discriminant function coefficients for sexing long bones in 1958, and since then, several studies on the Japanese bones and teeth have been published.
In this article, the author reviewed historical background of this method, explained statistical procedures for calculating discriminant function coefficients by direct as well as stepwise methods and reliability of individual discriminant function value, and discussed differences in coefficients and effectiveness of the functions between different populations. On the basis of experiences of the author, the following points were suggested for sexing bones and teeth effectively by the discriminant function method:
1) The sexing is highly reliable when a probability of a given sample being a male or a female, P(Gκ/y) on page 405, is equal to or greater than 0.7;
2) Authors who intend to publish papers related to this problem are recommended to provide all the raw data of the samples used, or at least those statistics which are required for calculating the above mentioned probability such as mean discriminant function values for male and female groups and a pooled variance or standard deviation of the function values;
3) The number of samples for each group is recommended to be 50 or more which allow to obtain a reliable covariance matrix needed for computing the discriminant function coefficients.
The author also showed an illustrative example of calculation of P(Gκy) using mean discriminant function values (yM and yF) and their pooled standard deviation (6). Finally the discriminant function coefficients, sectioning points and effectiveness of each discriminant function for the Japanese samples were shown in tables 1 through 9. In addition, table 10 gives statistical values for calculating P(Gκ/y), which were obtained from the raw data on the Japanese skulls and teeth provided by HANIHARA and KoizuMi (1979) and TANAKA et al. (1979).

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For the purpose of studying. the reduction of human dentition, an examination of dental diseases in the Kofun period was undertaken. Materials used were 22 maxillae and 21 mandibles with permanent or mixed dentitions, selected from 105 Japanese skulls from the Kofun period (protohistoric age of Japan). As the number of materials available was not sufficient to represent the character of the population, the purpose of this paper might be limited just to present the data obtained. By comparing these data to those from the later Jomon, Kamakura, and modern ages, however, it might still be possible to consider tentatively that the specificity of dental diseases in this period was similar to that in the later Jomon period, but more serious. The environmental pollution factor also seemed to be the main pathogenetic factor in the Kofun period, but a larger influence of the discrepancy than in the Jomon period was evident.

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We presented some data on the demographic and mating structure of Tobishima Island, in Yamagata Prefecture, evaluated some genetic parameters as a basis for the analysis of regional variation in physical traits, and compared the results with those from other island communities in Japan.
Tobishima was found to have a hierarchic population structure in which strong genetic isolation existed not only among the villages on the island but also between the island and the neighboring populations. The villages on the island were found to have effective population sizes between 68 and 120, effectivemi gration rates between 0.0619 and 0. 1902, and average inbreeding coefficients between 0.0387 and 0.0500. The corresponding breeding isolation coefficients were between 4.2 and 15. 2, suggesting that stochastic factors have brought about regional genetic variations among the villages and between Tobishima and the neighboring communities.

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In order to clarify the age and sex differences in the mandibles of adult Japanese from Hokuriku district, 106 male and 55 female mandibles of 20 to 50 years of age were studied from the anthropological point of view.
The results were as follows:
1) The most striking change of the bone with advance of age was seen in degree of projection of the protuberantia mentalis. In both sexes the projection became less in degree in the 20s and 30s, but in the 40s the degree increased again in the males, whereas decreased gradually in the females.
2) The gross configuration of the mandibular caput became progressively round with advancing age in the males, while in the females, it changed from a short ellipsoid in the 20s to a long ellipsoid in the 40s.
3) Other age changes observed in the males were those in the body height and the angle between the alveolar border and mandibular basis lines. In the females, gradual increase in various measurements concerning height of the mandibular ramus and gradual decrease in bigonial breadth were recognized.

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Skeletal maturation was analyzed in 1072 radiographs of the right hand and wrist in 458 pairs of identical twins and 78 pairs of fraternal twins, aged 12 to 18 years. Because skeletal maturity is already completed in the older children, the age groups of 12-14 years in boys and 12 years in girls were mainly discussed. Skeletal maturity was assessed by the K score, TW1 and TW2 methods, and heritability was evaluated by intrapair correlation, percent deviation and revised percent deviation, heritability indices, F-ratio and genotypic-environmental ratios. As regards estimation of heritability, all the skeletal scores and ages assessed by various methods showed high significant correlations with one another, and skeletal maturation suggested a high heritability which is almost the same in both sexes.

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Craniosynostosis defined as an abnormal premature suture closure in the skull may result in severe deformity of the cranium and, occasionally, deformity of the face with various clinical manifestation.
From the palaeopathological point of view, however, there are no case reports on the craniosynostosis in the human skeletal remains excavated from Japan.
Plagiocephaly, which has relatively low frequency of occurence among the primary craniosynostosis, was diagnosed from a skull of a 5 or 6 years old infant. The skull shows severe deformity due to premature suture closure on the macroscopic observation and many characteristic signs on the roentgenological examination.
In this paper, some important morphological features of the primary craniosynostosis are discussed in detail enough to diagnose the materials palaeopathologically with ease. Many other interesting problems such as the etiology, classification, frequency and associated abnormalities based on the clinical aspects are reviewed.

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Two series of measurements taken by one investigator and by several investigators on the same subjects were compared to examine the reliability of the data obtained in large-scale somatometric research. The series of differences was analysed using analysis of variance, and statistically significant inter-observer difference was observed in 17 out of 20 variables (Table 3). From a practical point of view, 7 out of 17 variables with statistically significant inter-observer difference should be excluded from analysis because of their great error variance (Table 4). It was suggested that the direct measurements were more precise than the subtracted measurements of the upper limb. The examination of possible effects of measurement error on several biological distances suggested that shape as well as size distance is affected by systematic measurement error. The influence of measurement error can be minimized by excluding the measurement items having great measurement error.

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Abstract The Diego blood groups of 2, 397 unrelated Japanese, 1, 142 from Tokyo and 1, 255 from Chiba, were investigated. The estimated Di^a gene frequencies are 0.047 in Tokyo and 0.048 in Chiba, which agree well with those obtained in previous studies. Tests for the Diego blood groups on 221 Japanese families with 328 children are also reported.

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This report provides distance coefficients among local populations of modern male Japanese. MAHALANOBIS' D2^s, Q-mode correlation coefficients, and PENROSE'S size and shape distances were computed on the basis of 33 cranial measurements shown in the text.

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