Statures of Toronto girls, grouped in one-year periods-Concluded. Height in centimeters. 150. 151 152 153 154. 155. 156 157 158 159 160 161 162 163. 164. 165. 166. 167 168 169. 170. 171 172. 173. 174. Cases. Average age 88 363 597 759 834 875 822 876 824 665 443 247 123 6.508 7.508 8.475 9.475 10.483 11.475 12.458 13.458 14.442 15.433 16.358 Average height.... 100.4 105.2 110.4 116.0 120.6 125.2 130.8 136.0 141.7 147.7 153.0 155.8 156.5 Mean variation ±4.26 ±4.80±4.80 +5.30 ±5.53 ±5.32 ±6.20±6.52 ±6.96 ±7.17 ±6.35 ±5.86±5.35 Corrected average. 110.4 116.0 120.7 125.3 130.9 136.1 141.9 148.0 153.3 156.0 156.7 The following table exhibits the statures of Toronto children as compared with American children in general: 10.5. 11.5. 12.5. 13.5. 14.5. 15.5. 16.5. Toronto 106.2 111.1 116.8 121.8 126.7 131.5 135.9 140.1 145.4 151.5 157.6 American 105.9 111.6 116.8 122.0 126.9 131.8 136.2 140.7 146.0 152.4 159.7 ... STATURES OF GIRLS, IN CENTIMETERS. Toronto 105.2 110.4 116.0 120.7 125.3 130.9 136.1 141.9 148.0 153.3 156.0 156.7 American .... 104.9 110.1 116.1 121.2 126.1 131.3 136.6 142.5 148.7 153.5 156.5 158.0 VARIABILITY OF BOYS' STATURES. Toronto... ±5.12 ±4.82 ±5.08 ±5.58 ±5.59 ±6.15 ±6.15 ±6.80 ±7.79 ±8.55 ±9.00 American.... ±4.80 ±4.92 ±5.22 ±5.53 ±5.66 ±5.90 ±6.32±6.80 ±7.71 ±8.66 ±8.87 ±7.75 VARIABILITY OF GIRLS' STATURES. Toronto .. 4.80 4.80 ±5.30 ±5.53 ±5.32 ±6.20 +6.52 ±6.96 ±7.17 ±6.35 ±5.86 ±5.35 American ..±4.64±5.07 ±5.25 ±5.58 ±5.73±6.18 ±6.83 ±7.57 ±7.37 ±6.69 ±5.96 ±5.79 It appears from these tables that on the whole the Toronto children are not as favorably developed as are American children, their statures being slightly shorter. The variability of the Toronto series does not differ so much from the general series as might be expected. The causes that modify the growth of children in a single city appear to be so great that the decrease in general variability is very slight indeed. The variabilities given in the preceding tables are those for the whole year. When the variabilities for each year are calculated from the averages of the trimonthly periods given on pages 1558-1564, a considerable reduction in the values takes place. Variability for 5.5. 6.5. 7.5. 8.5. 9.5. BOYS. Age in years. 10.5. 11.5. 12.5. 13.5. 14.5. 15.5. 16.5. The whole GIRLS. The whole year Quarterly ±4.80 +4.80 ±5.30 ±5.53 ±5.32 ±6.20 ±6.52 ±6.96 ±7.17 ±6.35 ±5.86 ±5.35 periods ±4.62 ±4.73 ±5.21 ±5.34 ±5.18 ±5.89 ±6.38 ±6.90 +6.85 ±6.13 ±5.73 ±5.63 a Six-monthly period. THE GROWTH OF FIRST-BORN CHILDREN. I have shown (Science, 1895, April 12) that the first-born children in Oakland, Cal., exceed in height later-born children. The data which were then available gave the following results. The columns headed "Differences" contain the amount to be added to the average statures and weights in order to obtain the measurements of first-born and later-born children. The figures in parentheses designate the number of individuals measured. |