The Ascent of Man 159 



key there is only a slight clouding after a considerable time and 

 no actual precipitate. When it is added to the blood of one of the 

 distantly related "half -monkeys" or lemurs there is no reaction 

 or only a very weak one. With the blood of mammals off the 

 simian line altogether there is no reaction at all. Thus, as a dis- 

 tinguished anthropologist, Professor Schwalbe, has said: 'We 

 have in this not only a proof of the literal blood-relationship be- 

 tween man and apes, but the degree of relationship with the dif- 

 ferent main groups of apes can be determined beyond possibility 

 of mistake." We can imagine how this modern line of experi- 

 ment Would have delighted Darwin. 



Embryological Proof of Man's Relationship with a Simian Stock 



In his individual development, man does in some measure 

 climb up his own genealogical tree. Stages in the development of 

 the body during its nine months of ante-natal life are closely 

 similar to stages in the development of the anthropoid embryo. 

 Babies born in times of famine or siege are sometimes, as it were, 

 imperfectly finished, and sometimes have what may be described 

 as monkeyish features and ways. A visit to an institution for the 

 care of children who show arrested, defective, or disturbed devel- 

 opment leaves one sadly impressed with the risk of slipping down 

 the rungs of the steep ladder of evolution ; and even in adults the 

 occurrence of serious nervous disturbance, such as "shell-shock," 

 is sometimes marked by relapses to animal ways. It is a familiar 

 fact that a normal baby reveals the past in its surprising power of 

 grip, and the careful experiments of Dr. Louis Robinson showed 

 that an infant three weeks old could support its own weight for 

 over two minutes, holding on to a horizontal bar. "In many cases 

 no sign of distress is evinced and no cry uttered, until the grasp 

 begins to give way." This persistent grasp probably points back 

 to the time when the baby had to cling to its arboreal mother. 

 The human tail is represented in the adult by a fusion of four or 

 five vertebrae forming the "coccyx" at the end of the backbone, 



