1. Hamlet of Kattsuru in the village of Chikumaji, Nagano Prefecture was subjected to a human ecological survey as a basis of rural sanitation and guidance of local family planning. The hamlet, 890-950m above sea-level, fills a narrow valley of a rivulet, Takenoiri-gawa, and is a typical highland community in the Central Japan. 2. There is cultivated area of 2.44 acres (1.12 acres of rice paddie and 1, 32 acres of dry field) per household in the average. Restricted by the geographical and climatic condition, the agriculture with this acrage corresponds to the sustenance limit. Most of the villagers seek to earn an extra income from semething or other : dairy farm, silkworm raising, civil engineering work or charcoal production to mention the main items. 3. Annual food expenditure per household in 1953 was Y101, 101 which was 61.8% (Engel coefficient) of the whole livelihood expenditure, Y178, 000. It must be mentioned, however, that the harvest of this year was generally poor, owing to extraordinary lack of sunshine and heat during the summer. In an ordinary year the Engel coefficient would be a little lower. 4. Uncultivated arable area is 14.9 acres for the whole hamlet of 78 households. This wasteland between the forest and the cultivated field produces hay for- the live-stock. The forest grows on a steep mountain side. So it is not practicable to change it into farming area. 5. Population of Kattsuru hamlet as of September 1953 was 408 (219 males and 189 females). Ane increase would entail a reduction of livelihood level, since no effective means of increasing the population capacity are available. 6. This community, considerered as a whole, is economically incapable of improvement of sanitary conditions. Suggestions derived from the present survey are : (i) Avoid further increase of population. (ii) Emigratin out of the hamlet ought to be encouraged. (iii) Mechanization of the agriculture should be introduced. (iv) Dairy farming, now isolatedly introduced, ought to be encouraged. (v) Road communication, about 4 km. connecting the hamlet with Ono station of the Central Line of the National Railway should be repaired or improved, at least to make it passable for bicycles.
The concept of “ mental deficiency ” depends chiefly upon the grades of intelligence, so that their measurement by various intelligence tests isstill highly estimated even at present for the diagnosis of the deficiency. Recent studies on the frequency distribution of I. Q's in group intelligence tests as well as heredito-clinical investigations in this domain justify the proposal that mental deficiency cases should be classified into two types: the ordinary and the extraordinary. From this view-point, the stature growth in cases of mental deficiency, both endogenous and exogenous, was chosen as an indicator for the purpose of classification, and the investigation was held as to what sort of relations existed between this biological index and the intelligence. Cases of the juvenile delinquent, totaling 1010, were our material. As to the stature, each case was compared with the average stature of the Japanese boys or girls, and thus we have obtained the percentage, which was named as Stature Index. The following result was obtained by the statistical management between the above mentioned indices and the I. Q.. 1) Among the mentally deficients with pathologically retarded stature growth cS. I. below 93), there were many whose I. Q. was below 50, whileI. Q. amounted, in many cases, above 51 among those indicating almost normal stature growth (S. I. above 94). The author suggested to divide the mentally deficient intotwo groups, subnormal and pathological ones; the former reveals only the retardationto the degree of the subnormal intelligence, while on the other hand the latter indicatesrelatively low I. Q. which is rather regarded as a partial phenomenon of general growth disturbances. The investigations thus performed using stature as an index, seems to favor the above-mentioned stand-point. 2) The overlapping of these subnormal and pathological groups was found to fall in the range between 50 and 80 of I. Q..