THE EVOLUTION OF MAN 



division of the Secondary age. It is important/, 

 *to note at the same time that a hand with five 

 fingers and a flexible thumb, which have been so 

 faithfully preserved by prosimiae, monkeys, an- 

 thropoid apes and man, are found among the 

 climbing species of marsupials, especially theX 

 /American oppossum. 



Before the external nipples of the breast are 

 formed in the human embryo, the milk gland is 

 formed in the skin. If we remember the bio- 

 genetic law, it seems to us that the milk gland 

 existed in our ancestors at a certain stage be- 

 fore the genuine nipple of the breasts came into 

 existence. At the same time we see the human 

 embryo at a certain early stage of its development 

 with a very peculiar construction of its posterior 

 opening. The opening for the products of the 

 urinary and sexual organs is found in the rectum, 

 so that there is only one single opening for all 

 three things, the products of the digestive, the 

 urinary, and the sex organs. It is not until the 

 third month that a partition is formed in the 

 rectum of the growing human being by means 

 of which henceforth these excretions are divided 

 and discharged through two openings, one for the 

 products of the urinary and sex organs, the other 

 for the products of digestion. This succession of 



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