A series of experiment was made for the purpose of clarifying the respective influence in the distribution of stress and internal force, which are produced by the masseter and temporalis muscles in the upper facial skeleton at the action of biting. The experiments were to measure the strains in the macerated skull under static loading. The analyses of stress and internal force were made from the strains measured in the fronto-nasal, fronto-zygomatic, supraorbital and infraorbital regions. They were approximately decomposed according to the force of each muscle. In general, the action of the masseter muscle has a tendency to strengthen the tensile stress, whereas the action of the temporalis has a tendency to strengthen the compressive stress. Basing on the results obtained, some commentaries were done on the functional interpretations in the morphological studies of various authors dealing with the facial skeleton.

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The outer ear form is strongly governed by genes. How the ear form varys among isolated groups of the same species is of interest in population genetics. From comparative anatomical point of view, it seems effective to apply the outer ear form as one of the determining basis of species. But, until now, there is scarcely any description of the ear of ape or monkey.
Thirty-seven monkeys (Macaca irus) consisting of 8 Philippine-born, 9 Thailand-born, 13 Malaya-born and 7 unknown were observed. In addition, 2 Formosa-born and Rhesus monkey were examined.
As classification of the outer ear form, an ear is divided into four parts ; upper part, Darwinian tubercle, outer contour and ending part of the ear. Each individual characteristics which are shown in Figure 1 to 6 were selected and classified considering the form of portions and the grade of development.
The analysed data on the intraspecific variation among Philippine, Thailand and Malaya groups are as follows:
Philippine: L_h-1M_0-1D₁R
Thailand: L_h-n-1M_1-2A-D_0-1-2R
Malaya: L_h-2T-M_0-1D₁R

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From mcroscopic and microscopic observations on the laryngeal region, especially on the laryngeal air-sac (Saccus laryngis) of PRIMATES belonging to 9 families, 30 genera, 64 species, the following results were obtained (Table 1).
1) The Saccus laryngis and or Sacculus laryngis was found inside or outside the larynx in P RIMATES of all the 64 species (Table 3).
2) The Saccus laryngis were classified into 5 types, MSA, MIP, MIA, LS and VL, according to the distribution of their openings. In PROSIMII and Cebidae of ANTHROPOIDEA an intergeneric variation was observable in the opening types. In Cercopithecidae only 2 types of opening, MSA and VL, were found. In Cercopithecidae expect for Colobus the Saccus laryngis distributes outside the larynx only of type VL without any intergeneric variation. In Hylobatidae and Pongidae the Saccus laryngis is open at the opening of type VL.
3) The distribution of Saccus laryngis were classified into 6 types, (A), (B), (D), (E) and (F). In most cases of PROSIMII and the majority of Ceboidea of ANTHROPOIDEA, the Saccus laryngis distributes inside the larynx, which is type (F), or very small part of the Saccus laryngis distributes outside the larynx, which is (E) type. In Cercopithecidae and Hylobatidae of ANTHROPOIDEA the Saccus laryngis partially reaches the Regio pectoris anterior, which is (B), (C), (D) or (E) type according to the proportion of distribution outside the larynx. In Pongidae the largest part of the Saccus laryngis ditributes outside the larynx, which is (A) type.
4) Between Cebide and Cercopithecidae of ANTHROPOIDEA, the primary variation in the opening type appears, and the secondary variation from MSA to VL appears in Colobus of Cercopithecidae, the form of the opening, from which no variation in Saccus laryngis distributes outside the larynx, is considered to be related to the Systematical position of each family.
5) When the correlation between the distribution of Saccus laryngis and the body weight in Macaca is considered, the sexual difference in the size of Saccus laryngis is presumed to depend upon the difference in body size between the male and female which become distinct after the appearance of secondary sexual character.
6) The appearance of Saccus laryngis in PRIMATES is considered to result from their characteristic arboreal locomotion. This Saccus laryngis has been generally said to play a part in evolving them to erect bipedal walking, in other word, in releasing them from manual walking. It is considered, however, that in PRIMATES the difference in the opening type and or the distribution type are related to the difference in the locomotion behavior. For example, the type VL is related to the brachiation, and type MSA to the arboreal quadrupedlism. The variety of the opening type in PROSIMII and Ceboidea of ANTHROPOIDEA is considered to have some relation to the variety of their locomtion behavior.
7) In most PRIMATES the Sacculus laryngis exist separately without any relation to the opening of Saccus laryngis. In Hylobatidae and Pongidae this Sacculus laryngis vares into a specialization and become the Saccus laryngis whose distribution expands widely. The Sacculus laryngis of Hominidae is such an ordinary one as most of Non-human PRIMATES have.

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Patterns of attrition of the dentition in Macaca were studied, from the morphological and functional points of view, by using 602 skulls consisting of Macaca fuscata and Macaca irus.
The pattern of attrition in each kind of thee teeth appears to depend on not only its shape but also movements of the mandible.
With the advance of age, the remarkable sexual dimorphism concerning the pattern of the dentition is found out in canines and lower first premolars. The development of attrition is very rapid at the lingual surface of lower incisors, and the layer of dentine is exposed over the whole lingual surface in a considerable early stage as compared with other teeth. Such a pattern is thought to be closely related to the very thin layer of enamel on these lingual surface of the incisors.

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The mesiodistal crown diameters were measured on the dentition of three groups in the Pima Indians. The first group (Group N) carries the upper lateral incisors of normal shape, the second (Group R) those incisors of reduced or conical shape, and the third (Group M) malformed or over-developed type of incisors. The three groups showed more or less extent of differences as a whole, namely, Group R is smaller and Group M is larger than the Group N. These differences were also analysed by the technique of multivariate analysis and the significance related to the human dental evolution was discussed.

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The present anthropometry has been established using the data of adult Japanese, 168 males and 89 females, the principal component and the varimax rotation methods were applied to 16 measurement items. Five factors were extracted and four of them were interpreted as soft and skeletal components, blood pressure and grip strength. Factor 5 was not interpreted but it revealed sexual discrepancies of factor loadings. Age had not its own peculiar factor. The individual factor scores were introduced in the present study. Since the magnitudes of scores indicate personal characteristics, the classification was made of individuals on the basis of factor scores.

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[in Japanese]

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