Using certain inbeed strains of mice (SM, DDd, and NA- II strain) and mixed bleed strain, F1, (SM x DDd), the author studied the sense of taste against PTC (Phenyl-thiocarbanlide), saccharine, acetic acid, and NaC1, and got the following results. 1. In the case of discrimination test against water and test solution, NA- IL strain was most sensitive against every test solutions, and mixed bleed strain was far more sensitive than parent strains. 2. In the case of discrimination test among test solutions, same tendency was observed. 3. The author could not find any correlations between the threshold of discrimination and the average of water (or solution) intake. 4. In every experiments, the mouse hesitated to drink PTC solution at very low concentrations.
Female pelvis, as the most important part of maternity, has repeatedly studied not only in Japan but in foreign countries, but few with the research from the point of view of relative growth throughout thewhole ages till maturity. This study of 1543 normal pelvis, sampled at random by sex, year-age (month-age in infancy), through the ages between 1 month and 17 years, was attempted to clarify the developmental changes of pelvic cavity by means of stochastical analysis on the radiographic measurements. The results obtained are as follows. (1) The pelvic cavity was found to become larger with the age advanced, and to show a particularly rapid. growth for three months after birth, between the ages of 1 and 4 years, and also in the puberty. (2) Sexual differences of pelvic cavity were observed already in the infancy, that is, the upper structure in males and the lower structure in females were greater than those in opposite sex. After 10 years old, the growth of pelvic cavity in females was remarkable and in the puberty every parts of the cavity measured in females was greater than that in males. (3) The investigation on relative growth between each parts of the pelvic cavity measuied in this study revealed that in the early infancy the maximum distance between both obturator-foramina increased most rapidly while the distance of Wollenberg's Y-cartilage-line did eminently in the later infancy and also in the puberty. The growth of breadth of the cavity was superior to that of the height in the infancy, while after that the latter became superior to the former ; in the puberty the both were almost of the same increase from the point of view of relative growth. (4) The growth of the pelvic cavity had so close relationship to that of the pelvis that the coefficients of correlation between them gave very high possitive values.
For the purpose to study the influence of the physical growth on the development of activity, 2063 infants were examined during one year from April of 1956 at random by sex, month-age, birth-month, from the infants between the ages of 1 and 20 months who had been registered at a certain health center in Aichi prefecture. The samples were taken measurements of their height, weight and taken the direct X-ray photographs of their hip-joints, and tested for their activities. After a severe selection 1230 X-ray films (600 of boys and 630 of girls) out of 2063 were finally taken mesurements of several parts of the hip-joints. Stochastical analysis on the measurements of these samples brought the following results. (1) The infants who got to higher stages of motor development than the average were found to have greater heights, weights and hip-joints than those who failed to get in the same chronological age. (2) The acquisition percentages of the activity associated with the measurements of the hip-joints, regardless of the parts measured and the items tested, a) represented an S-shaped curve, b) arised rapidly higher near the measurements of hip-joints at which 50% of the infants had acquired the activity, and c) became to show a slow raise after that point and showed this tendency more obviously in the higher stages of motor development. (3) No sexual differences were found in the measurements of hip-joints at which 50% of the infants had acquired the activity. (4) The infants who could stand up and those who could walk were clarified to have a greater growth not only of standing height, body weight but of the breadth of the hip-joints than those who could not respectively in the same chronological age.
The development of body weight, height and chest of the premature infants in childhood who were born in Shirakawa Area during the period 1951 to 1956 were mesured. The results of the survey were obtained as follows: 1. The bodyweight, height and chest of the premature infant caught up with mature infant at the age of six. 2. The premature infants in Shirakawa Area were inferior to the premature infants in Tokyo from the view-point of the. development.
The death rate of premature infants who were born in Shirakawa Area during the period 1948 to 1950 was calculated. In childhood the death rate of premature infant is higher than of mature infant. The most fatal disease of premature infant is a disease ofthe respiratory organs.