The authors dercribed the crown characters of the Japanese permanent dentition on the exterior surface of enamel and on the interior surface of dentinoenamel border in previous chapters. The present article gives general conclusion as the last chapter of this work. The junction of the enamel and dentin has been investigated in several ways in the past. We used acid to dissolve away the enamel for our studies of the dentin core, and interpreted many of the outer enamel morphologic markings related to the dentin core topography.
On the dentinoenamel junction of the teeth of recent man, many primitive characters are frequently and clearly observed. These characters may be homologous with those observed on the enamel surfaces of the permanent teeth of fossil and recent primates and the earliest known hominids, and of the deciduous teeth of fossil and recent hominids. Taking the results of our studies into consideration, it seems clear that the characters on the dentinoenamel junction show phylogenetically more primitive or conservative conditions in relation to the exterior surface of the enamel layer, so a morphologic study of the dentinoenamel junction should play an important role in morphologic interpretation of various dental traits and studies on phylogeny of the dentition.

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The sexual and racial differences in femoral curvature were studied based on 101 femora in the Japanese and the Ainu. In the females, the point of maximum curvature located more distally, and, only in the Japanese, the diaphyseal curvature was greater than in the males. The femoral head-greater trochanter length is shorter in the Ainu than in the Japanese. Only in the males, the Ainu shows more striking curvature and more distal location of the point of maximum curvature compared to the Japanese. Diaphyseal curvature of the femur may be most pronounced in the Mongoloid groups including the Ainu, least in the Negroes, and intermediate in the Whites.

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The frequency distribution of middle and basal phalangeal patterntypes was investigated among 150 male Shaikh Sunni Muslims of Delhi. Both middle and basal phalangeal segments of the finger are characterized by high frequency of arches (46.16% and 40.00%, respectively), followed by the straight patterns (28.91% and 27.80%). Vestigeal loops, loops and whorls were exclusively noticed on the basal phalanges.

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Abstract The growth line of shells showing yearly and daily periodicities of deposition is a useful characteristic for reconstructing prehistoric seasonality of shell gathering. For such investigations, basic studies in recent molluscs are required. This report discusses the results of vital staining and planting (16 days) of the clam, Meretrix lusoria. In the scanning electron photomicrographs, growth lines of variable thickness were observed. They were classified into 5 types (A-E) according to the combination of the thicknesses along the surface of maximum growth (_??_3μ, 3-1μ, <1μ), and those in the "inner zone" of outer layer (_??_ 1μ, <1μ). Among them there were 2 categories: the growth line of the primary order (Types A and B) well discernible in the "inner zone" and more or less conspicuous at the surface of maximum growth, and the secondary one (Types C-E) barely visible or invisible in the "inner zone" and fainter at the surface of maximum growth. In the 2/3 of the specimens, the primary line included only the Type A, the Type B being absent, and in the rest, the Type A formed the great majority in it, a few of the Type B being included. In both cases, the totals of the frequency of these primary lines (only A or A+B) in each specimen were always exactly 16, coinciding the number of days of emplanting. The primary and the secondary growth lines are considered as that of daily and subdaily formation, respectively. The growth increment between the growth lines was seen to be composed of an alternation of lighter and darker zonules.

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