year period. The solid line represents the boys, and the broken 

 line the girls. The lesser variability of the girls is evident 

 from the greater concentration of the cases about the mean. 

 It is also interesting to note that the position of the first quar- 

 tile point, that is, the height below which 25% of the cases 

 are found, is almost identical for the two sexes; it is 59.91 inches 

 for the boys, and 59.88 inches for the girls. On the other 

 hand, the third quartile points, or the heights below which 

 75% of the cases are included, are more widely separated, 

 being 64.17 inches for boys, and 62.93 inches for girls. 



As has already been pointed out, the boys are taller than 

 the girls, the averages being 61.99 and 61.35 inches respectively, 

 or a difference of .64 inch. The actual difference between the 

 average heights is even greater, because of the fact that the 

 girls wear higher heels. Accurate figures are not available, 

 but it is safe to say that an additional half -inch may be added 

 to the above figure (.64 inch) to give the net difference in the 

 average heights of the two sexes. This difference is somewhat 

 greater than that found by other observers. The data of 

 Bowditch,* for example, give a net difference of .47 inch in 

 favor of the boys for the two-year period, and those of Boasf 

 give a difference of only .10 inch. 



These sex comparisons are much more significant, however, 

 when made for each of the two years, and not for the two 

 years combined; for the height relations of the two sexes 

 present important differences in the individual years. This 

 leads us to a discussion of gain in height of boys and girls 

 during the two years covered in our investigation. It must 

 be emphasized that our study is an extensive and not an in- 

 tensive one. Our data do not cover individual children, each 

 studied at various stages of development. Each child, at 

 whatever age, was under observation only once. 



The following table gives the average heights for each of 

 the eight quarter-year periods for the boys and girls: 



*H. P. Bowditch, "The Growth of Children" (8th Annual Report 

 of the State Board of Health of Massachusetts), Boston, 1877. 



fFranz Boas, "The Growth of Toronto Children" (Report of the Com- 

 missioner of Education for 1896-7), Washington, 1898. 



Boas and Wissler, "Statistics of Growth" based on a study of school 

 children in Worcester, Mass. (Report of the Commissioner of Education 

 for 1904), Washington, 1905. 



Franz Boas, "Changes in Bodily Form of Descendants of Immigrants" 

 (Vol. 38. Reports of the Immigration Commission), Washington, 1911. 



