TRANSACTIONS OF SECTION H. 771 



from the stage of absolute dependence on others to the acquisition of the power of 

 bipedal progression, important modifications in the structural arrangements both 

 of the spine and lower limbs have to take place. At the time of birth the infant's 

 spinal column exhibits only two curves ; one, corresponding to the true vertebrae, 

 extends from the upper end of the neck to the lowest lumbar vertebra, and the 

 concavity of its curve is directed forwards ; the other and shorter corresponds to 

 the sacro-coccygeal region and also has its concavity directed forwards. In the 

 number and character of the curves, the new-born infant difi'ers materially from 

 the adult man, in whose spine, instead of one continuous curve from the neck to 

 the sacrum, there are alternating curves, one convex forwards in the region of the 

 neck, succeeded by one concave forwards in the region of the chest vertebrae, 

 which again is succeeded by a marked convexity forwards in the vertebrae of the 

 loins. The sacro-coccygeal region continues to retain the forward concavity of the 

 new-born child. The formation and preservation of this alternating series of 

 curves is associated with the assumption of the erect attitude, and the development 

 of the lumbar convexity is correlated with the straightening of the lower limbs 

 when the child begins to walk.' 



When the child is born, the curvature of its spine in the dorso-lumbar region 

 approximates to that of an ordinary quadruped in which there is no lumbar con- 

 vexity, so that the spine in that region presents one continuous curve concave 

 forwards. For some time after its birth the infant retains the quadrupedal 

 character of the spinal curve in the dorso-lumbar region, and, as it acquires nervous 

 and muscular power and capability of independent movement, its mode of pro- 

 gression in the early months by creeping on hands and knees approximates to that 

 of the quadruped. It is only after it has attained the age of from a year to sixteen 

 months that it can erect its trunk, completely extend the hip and knee joints, and 

 draw the leg into line with the thigh> so as to form a column of support, which 

 enables it to stand or move about on two feet. Hence there is this great difference 

 between the young of a quadruped and that of a man, that whilst the former is 

 born with the dorso-lumbar curve proper to its attitude, and which it retains 

 throughout life, the chUd does not possess, either when bom, or for some months 

 after its birth, the characteristic spinal curves of the man. These curves are there- 

 fore secondary in their production; they are acquired after birth, and are not 

 imprinted on the human spine from the beginning, though the capability of 

 acquiring them at the proper time is a fundamental attribute of the human 

 organism.* 



It has sometimes been assumed that the acquisition of the erect attitude by the 

 young child is due to the fostering care of the mother or nurse ; that it is a matter 

 of training, encouragement and education, without which the child would not 

 raise itself upon its feet. I cannot, however, agree with this opinion. If one 

 could conceive an infant so circumstanced that, though duly provided with food 

 fitted for its nutrition and growth, it should never receive any aid or instruction in 

 its mode of progression, there can, I think, be little doubt that when it had gained 

 sufficient strength it would of itself acquire the erect attitude. The greater growth 

 in length of the lower limbs, as compared with the upper, would render it incon- 

 venient to retain the creeping or the quadrupedal position. 



We cannot lose sight of the important influence which, altogether independent 

 of education, is exercised by parents on their offspring. The transmission of 

 hereditary qualities, through the germ from which each individual organism is 

 derived, is one of the fundamental and most striking properties of the germ plasm. 

 Characters and peculiarities which appertain not only to the family of which the 

 individual is a member, but also to the species to which he belongs, are conveyed 

 through it from one generation to another. Hence, as the capability of assuming 

 the erect attitude and of thus standing and moving on two feet have been attri- 



• Professor Cleland, in Reports of British Associatioii, 1863, p. 112. 



^ In his work on the Origin and Progress of Language (vol. i. p. 173, Edinburgh, 

 1773), Lord Monboddo held that the erect position in man is an acquired habit, and, 

 like speech, is acquired with difficulty and as the result of training, 



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