A new measuring instrument was designed and the degree of the shovel-shaped character in the upper central incisor was measured in terms of the largest depth of the lingual fossa from a chord between the mesial and distal marginal ridges. This method allows continuous representation of the shovel-shaping which has so far been treated as a discrete trait. In this article, some basic problems related to this method were discussed and merits of quantitative analyses of the shovel-shaped incisors were emphasized.

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The enduring capacity of the erectores spinae muscles for sustained back extension was investigated in 8 normal males at the tensions of 70, 50, 40 and 30% of the maximum strength with a specially deviced dynamometer. Relatively prolonged endurance time was obtained at lower tensions; the critical tension endurable for 10-20 minutes was supposed to be 20-30% max., though muscular pain appeared already before the half of endurance. Heart rate increase was moderate. Conflicting trends were demonstrated between the mean amplitude and the slowing of EMG of the erectores spinae. The work load suffered by the latter in upright standing was assessed electromyographically as less than 2-3% of the maximum activity, and at most 20% in the case of forward bending at 45-60 degrees.

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From the distribution of the reaction time (RT), we intended to examine the normal standard process of essential psycho-somatic development as school grade advanced.
We investigated the phonating reaction times of repetitive tone click stimuli (20μ sec in duration, above 80db in strength) at irregular intervals of the city primary school children (from the 1st to the 6th, 246 persons) living in a calm residential area in Tokyo in 1967.
The results we obtained were not much differ from the data obtained 20 years ago by others.
The RT of primary school children were very variable temporally even in an experimental series of a same subject, especially in the lower grade children and the individual variation was also as much great.
This variability, however, was supposed to be the characteristic of the psycho-somatic growing process, so we examined the method of dealing with the figures of the RT paying great attention to the variability of it.
The results obtained were described in the form of histograms (ordinate-% trials of all in each group, abcissa-reaction time intervals of 50ms) and integration curves of the percentage of the total trials in successive reaction time intervals in each grade and sex group. From these distributions, it could be seen that the development was usually characterized by the faster and the more remarkable convergencies of the RT as the school grade advanced. And we confirmed that in integration curve, especially the following three factors, 1. reaction time in narrow sense, 2. intervals of deviation and 3. convergency, made apparent numerically the characteristic of the distribution of the RT and so displayed the trait of the developmental process in psycho-somatic function very clearly.
We examined, moreover, the characteristic of the RT of primary school children living the noisy region around jet air field, in comparison with the standard pattern of the psycho-somatic development of primary school children in Tokyo as mentioned above.
From the results, it was clearly observed that the noisy environment had much influence upon deviation and convergency of the RT and made the RT of children living in the noisy environment remain infantile pattern, preventing the RT from converging within shorter range and deviation of it from shortening as grade advanced.

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It is hoped that human life or activity will be studied from an ecological point of view. This paper is based on the data obtained in ecological field surveys in a fishing village of the Nasake Island, the Seto Inland Sea, Japan. The Nasake fishermen work every day on the sea near their settlements, specializing in the hand-line fishing (ippontsuri).
Main concerns of paper are descriptions and discussions about the people's system of activity (especially subsistence activities) in terms of its temporal structure, spatial structure, their correlations, the relationships between men's activities and women's activities, and so on. From our methodological point of view, the temporal and spatial structure is regarded as a primary expression of human activity system.

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Nine places on the ICU Campus, Mitaka city, Tokyo, have yielded preceramic material. At Loc. 28C, in the Tachikawa terrace by the Nogawa, the material was grouped as A, B and C in the soft-loam and upper part of the hard-loam (28C Upper) and C' in the middle hard-loam (28C Lower) with main tool types as follows: A : trapezes with a scraper; B : points, backed-blades, and gravers ; C : a point and a trapeze; C': backed-blades. 28C Upper tools are of obsidian, brought in from Mt. Hakone; 28C Lower are of local stone, from the Musashino gravel bed. Tools comprise 34% of the total weight of the obsidian ; they lack prepared surfaces and many retain some natural surface. The tools of local stone have prepared surfaces and are generally small, but the flakes are large, and few retain any natural surface. The differences are due to the availability of materials and the more efficient use of obsidian. Similarities to the Moro knife type suggest that Moro may be contemporaneous with 28C Upper, also with Tsukimino I, and Sunagawa follows shortly after. The backedblades of 28C Lower are similar to Ichibazaka examples, placing the latter after Moro.

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[in Japanese]

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