THE HUMAN BABY 203 



But it is to be noted that the anthropoid proportions 

 are retained in the human foetus until a relatively late 

 stage (see Figs. 74 and 75), and that even in the human 

 baby the proportion of arm length to leg length ap- 

 proaches the index of the Chimpanzee (see Fig. 70), the 



Fig. 74.^ — Human Embryo 

 105 MM. IN Total 

 Length. 



Fig. 75. — Human Embryo 

 195 mm. in Total 

 Length. 



I 



disproportionate growth of the human leg being largelj- 

 a post-natal development. At one stage of human 

 embryonic development the arm is longer tluin the leg 

 — a typically arboreal Primate feature; later the two 

 members are equal, and then the leg outstrips the arm 

 in relative growth. When the baby is born this Iniman 

 lengthening of the leg proceeds more rapidly; ^\heu the 

 child begins to walk the disproportion becomes more 

 marked (see Fig. 77), and the influence of this factor is 

 marked until about the period of the fifteenth year of 



