The (rrointh of St. Lou in Children. 61 



sufficiently alike to be rightly comparable. Information is 

 given concerning occupation of parents of St. Louis cliildren. 



A comparison of the weights of the (laughters of manual 

 tradesmen with the weights of the daughters of professional 

 men and mercliants teaches that the latter are very little 

 heavier than the daughters of manual tradesmen until the 

 period of pre})ubertal acceleration ; and that the weight of 

 girls is much more influenced by the material prosperity, or 

 social status, of parents during and immediately after the 

 period of prepubertal acceleration than in the earlier years of 

 growth. 



The nationality of tlie children should be considered in an 

 anthropometrical enquiry. The weights of children of Ger- 

 man parentage are compared with those of American parent- 

 age. The difference between the two is inconsiderable. 



When the curves of growth in weight, height standing, 

 heiglit sitting, span of arms, and girth of chest are drawn on 

 the same s\^stem of co-ordinates, the attention of the observer 

 is arrested by the difference in the development of girls and 

 boys during the period of prepubertal acceleration. Girls 

 enter this time of rapid growth at age 11 or 12, two years 

 earlier than bo3^s, and during several years are larger than 

 boys of the same age. The ages at wliich girls begin to be 

 larger than boys are nearly the same in all five dimensions 

 named above, and a similar correspondence is seen in the age 

 at which girls cease to be larger tlian boys. The sexual 

 difference just noted is not present in ex[)ansion of chest, or 

 in strength of squeeze, or in any head or face measurement, 

 except height of face from hair-line to point of chin. Boys 

 have therefore a larger expansion of the chest, greater 

 strength of squeeze, and greater length and width of head, 

 and height and width of face than girls throughout their 

 period of growth. 



The duration of the period during which girls are larger 

 than boys in weiglit, lieight standing, height sitting, span of 

 arms, and girth of chest is shortest in span of arms, and is 



