1.In groups of South African Bantu and Caucasian women aged 3 M years, sub-divided into those having had (i) none to two or (ii) seven or more children, measurements of radiographs of the second metacarpal and of the humerus were made in respect of length, cortical thickness, cortical index, cortical area/total area, cross-sectional area index and cortical/surface area ratio.2. In Bantu mothers of large compared with small families, there were no significant differences in the means of corresponding variables. This was also the case with the Caucasian mothers. Bantu mothers of large and small families had significantly lower mean values for most variables compared with those of Caucasian mothers of large and small families. In all four groups, ranges of measurements and indices were very wide.3. It is questioned whether Bantu mothers accustomed to a low calcium intake and to numerous pregnancies and long lactations, suffer from calcium deficiency. The problem of whether the high recommended allowances of calcium during these periods confer a clinically detectable benefit requires re-examination.

SummaryInformation on appendicectomy-prevalence was secured on 15,317 16-20-year-old South African pupils and students-Negroes, Coloureds (Eurafricans), Indians and Caucasians. Data were also obtained on crude fibre-intake, frequency of defaecation, and transit-time of digesta.Among students, 18-20 years, appendicectomy was very uncommon in rural Negroes (0-5%.) and periurban Negroes (0-9y/), slightly more common in urban Negroes (1F4y.), but very common in Caucasians (16-5%); prevalences in Coloured and Indian groups were low (1F7 and 29%y). Rural Negroes had a far larger fibre-intake, greater frequency of defaecation, and much shorter transit-time; yet, in the four ethnic groups in urban areas, despite wide differences in appendicectomy-prevalence, data on these variables were similar. Differences in other aspects of the bowel milieu int6rieur must therefore be sought. Corresponding studies were made on 1325 Caucasian pupils in Homes; their diet is less sophisticated (in respect of fibre, sugar and fat-intakes) than that of the general population. Pupils had slightly greater defaecation-frequency, lesser transit-time, and an appendicectomy-incidence only 23%/ of that of an appropriate control-group. The conclusion is reached that the causes of appendicitis are wholly environmental.

The aim of this study was to determine the degree of fluorosis in the primary dentition and the accompanying caries patterns in groups of preschool-children in high and low fluoride areas. Among 331 coloured children, aged 1-5 years, living in an area with water F concentrations ranging from 2.2 to 4.1 parts/10(6), 82% were caries free and the dmft values ranged from 0 to 15 with a mean dmft of 0.8 +/- 2.1. Varying degrees of fluorosis in the primary teeth were present in 50.6% of the children. In 177 coloured children of similar ages from an adjacent area with 0.2 parts/10(6) F in the drinking water the dmft values ranged from 0 to 20 with a mean dmft of 5.4 +/- 5.8. Only 28% of the children were caries free. None of the children in this area had fluorosis. The caries prevalence was significantly higher in the low fluoride area than in the high fluoride area. The degree of fluorosis found in the primary dentition in the children from the high fluoride area was higher than had been anticipated and was accompanied by a very low caries prevalence.