The deflecting wrinkle appearing in the mandibular second deciduous molars of the Japanese residing in Kyushu, Japan, was studied by the authors, utilizing the hard plaster models of the mandibular teeth. Five hundred and thirteen mandibular second deciduous molars (280 males and 233 females) were examined in this study, and the appearance frequency of the deflecting wrinkle as well as its relations with the crown measurement values or other primitive traits were investigated. Also, the deflecting wrinkle that appeared in the first deciduous molars and first molars adjacent to the second deciduous molars was studied for comparison. The results of the investigation are summarized as follows:
1. The appearance of deflecting wrinkle in the mandibular second deciduous molars is 75% while that of the first molar is 43%. A significantly positive correlation is observed between both teeth.
2. Positive correlations are observed between the deflecting wrinkle and the 7th cusp and also with the central ridge of metaconid in the study of the correlations of the deflecting wrinkle and other primitive traits.
3. No correlation is observed at all between the distal trigonid crest of the mandibular first deciduous molars and the deflecting wrinkle of the mandibular second deciduous molars' However, the deflecting wrinkle of the second molars are considered to be one of the variations of the distal trigonid crest of the first deciduous molars.
4. The correlations between the deflecting wrinkle of the second deciduous molars and the central ridge of metaconid of the first molars and that of the central ridge of metaconid of both teeth are observed to be positive significantly.
5. In the relationship between the deflecting wrinkle and crown measurement (mesiodistal, buccolingual diameters), such tendency was seen as the better the development of the deflecting wrinkle, the larger the tooth size is.
That the deflecting wrinkle of the mandibular second deciduous molars appears in the 75% of the Japanese residing in Kyushu is considered to strongly indicate the so-called Mongoloid racial tooth characteristic. In view of its correlations with other traits and measured values, the deflecting wrinkle is believed to be one of the primitive traits.

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Using the measures of genetic, migrational, and geographic distances, the population structure was analyzed of populations in Kamishima, Toshi, Momotori and Toba, Mie Prefecture, to clarify the population genetic relationships among these populations. In order to measure the migrational distance relationships between the populations, a new statistic based on surname distributions was adopted. The genetic distance relationships were estimated by the method of HARPENDING & JENKINS (1973) and the analysis was based on the variability in 10 blood group, serum protein and red cell enzyme systems. Further, in order to give a visual interpretation of these distance matrices, diagrams were represented based on genetic affinity and dendrograms were reconstructed based on both genetic and migrational distances. Finally, the correlations between genetic, migrational, and geographic distances separating the populations were examined.
It is concluded that half of the genetic diversity among these populations may reflect the variation caused by inter-populational migration and the remaining half may correspond to random variation.

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The Ryukyu islanders (700 males and 675 females) and the inhabitants of southern Kyushu (220 males and 200 females) were surveyed during the years from 1972 to 1977 (Table 1).

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Principal component analysis (PCA) and cluster analysis were applied to a correlation matrix based on 44 somatic measurements taken on 112 males aged from 18 to 27 years, and the results were compared with those of previous studies. The purposes of this study are: 1) to clarify the reason why the 3rd principal component is varied in meaning from case to case, and 2) to confirm that PCA offers effective criteria for the grouping of the measurement items. Initial selection of the measurement items is considered to be responsible for the varied manifestation of the 3rd principal component. All the studies reviewed show similar grouping of the measurement items based on the first three principal components, except for the location of sitting height. Cluster analysis supported the grouping based on PCA on the whole. Selection of measurement items was attempted on the basis of above-mentioned grouping, and tentatively 20 items were selected.

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This study was attempted to make new equations for predicting body density of Japanese young men from skinfold and/or girth measurements. The subjects were 31 healthy young men aged from 19 to 25 years old. Body density and some anthropometric parameters, such as body weight, height, skinfold thickness and girth, were determined. The body density was estimated by underwater weighing method. Subjects were immersed underwater in the squat position and instructed to breathe out as completely as possible. Then underwater weight was measured with use of load cells. The residual lung volume was measured outside the water tank by neon dilution technique in the same position as underwater weighing. The mean body density of young men was 1.073 g/ml and located at the middle level of the other data for various populations. Two prediction equations of body density with a high degree of accuracy were obtained from the stepwise multiple regression analysis. One equation used triceps and abdominal skinfolds and the other consisted of chest, triceps, subscapular and iliac skinfolds as predictor variables (cf. Table 2). On the basis of present data, differences between the actual and predicted values from various prediction equations obtained by the authors and other investigators (cf. Tables 3, 4) were compared to evaluate the validity of the equations.

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1) Using the data on Japanese, Pima Indians, Australian Aborigines and American Negroes, the discriminant function coefficients for sexing were computed on the basis of the mesiodistal crown diameters of 7 maxillary and 7 mandibular permanent teeth excluding the third molars.
2) Between-sex differences in the mean values were tested in each population (Tables 1 and 2). Although the significant differences were found in few teeth, the discriminant function coefficients were computed on the basis of all the teeth measured. The reason of this procedure was the fact that there were more or less within-group correlations so that the teeth without significant difference could not be excluded from the computation.
3) As a result of a direct method of computation, the effectiveness of 76% was obtained in Japanese (Tables 3 and 6).
4) A stepwise method employing Wilks' lambda as a statistical standard selected 6 variables, and gave the effectiveness of 77% in Japanese (Tables 4 and 5). These 6 variables agreed quite well with the teeth showing higher M/F ratio reported by GARN et al. (1964),
5) Effectiveness of sex discrimination showed considerably large differences among 4 populations compared. The effectiveness was apparently higher in the populations which showed larger sexual dimorphism in the crown diameters (cf. HANIHARA, 1978), and vice versa.
6) Using P(Gκ|ys) which shows the probability that the individual s belongs to the male or female group sexs, the of the individual s can be more effectively discriminated. In Japanese, the discrimination is almost certain when P(Gκ|ys)>0.7. This probability is computed by the formula shown in the text, in which Pi is a prior probability that the individuals belongs to the group k, ys is a discriminant function value for individual s, yk is a mean of the discriminant function values in the group k, and Σy is a pooled covariance matrix.
7) A point of advantage to use the dental crown diameters for sexing is its effectiveness on the younger individuals. The discriminant function coefficients so far reported for the skeleton are effective only on the adults, but the coefficients reported in this article can be applied on the individuals whose second molars were erupted, or the individuals over around 12 years of age.
The authors are deeply indebted to Dr. A. A. DAHLBERG of the University of Chicago, Dr. L. A. ALTEMUs of Howard University, and the late Dr. M. J. Barrett of the University of Adelaide who kindly permitted one of us (K. H.) to measure the excellent dental casts.

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Biological distances among the Japanese, the Hawaiians and the Pashtuns were calculated using the male permanent dentition. Applied coefficients of distance and similarity were PENROSE's size and shape distances, MAHALANOBIS' generalized distance, canonical variates and Q-mode correlation. And these affinities were again computed in order to produce a shape distance based on Q-mode standardization of the raw data. In addition, HAYASHI's quantification theory model IV was applied for these coefficients of affinities, and such coefficients were compared in a two dimensional space. It was consequently found in this study that the D2, canonical variates and Q-mode correlation coefficients produced better results for their determination of affinities in odontometric taxonomy of these populations. Moreover, the D2 and canonical variates being converted to shape measures through Q-mode standardization of the raw data, they also produced more meaningful results.

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The characteristics of the relatively irregular two-dimensional form, as often seen in research in prehistory or anthropology, are rather difficult to be quantified by the usual measurements of length and angle. The pattern recognition method is most desirable for those characteristics. However, it is usually difficult for the researchers in prehistory or anthropology to use huge apparatus for the pattern recognition. Hence the present author made a new method of measurement, called inertia moment method, which is intermediate between the ordinary method of measurement and the method of pattern recognition. It can be used without such apparatus. An application of this method to the lithic assemblages of the Middle Paleolithic site of the Douara cave showed that this method was useful for numerical analysis.

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Labolatory of Physical Anthropology, Kyoto University Forty-two external (non-metrical) characters were investigated in 1799 Japanese monkeys of 9 local populations (Yakushima, Koshima, Takasakiyama, Shodoshima, Arashiyama, Hakone, Boso, Shigakogen, and Shimokita).
The incidences of these characters are analyzed with special references to their age and sex. Also the inter-side, inter-limb (between hands and feet), inter-character correlations and those between mothers and offspring are examined. The usability of these characters for inter-population comparisons are discussed.
1) External characters become multiform on the early developmental stages of the Japanese monkeys, and most of them show sex differences in the ages of their emergences. I group the characters into 3 groups on the basis of the age/incidence patterns (see Fig. 2), and choose the available age class of each character corresponding to these patterns in order to use them for inter-population comparisons.
2) Twenty-two out of the 42 characters show significant sex differences.
3) Significant inter-side and inter-limb correlations are shown in all characters except for "Deficient pigmentation of nail ".
4) Significant inter-character correlations are shown on 9 pairs of the 11 characters in males and 10 pairs of the 16 characters in female.
5) Significant correlations between mothers and offspring are shown in 13 out of the 20 characters. The characters showing high correlations at 0.10 level (which are examined in only females) are more in the characters with low sex differences than those with high sex differences.
6) Significant inter-subspecies differences between Macaca f uscata fuscata (Arashiyama population) and Macaca fuscata yakui are shown in 14 out of the 20 characters.
If external characters are treated cautiously, considering the above-mentioned results, they
are usable for inter-population comparisons.

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