THE FACTORS OF HEREDITY. 97 



to the present generation. The elements of health 

 and disease, of virtue and vice, of angel and ani- 

 mal ; together with the inevitable results of obeyed 

 and broken laws, throughout all the centuries that 

 have come and gone, since God "breathed into 

 man the breath of life, and he became a living 

 soul" are the gift of heredity to us. 



The science of heredity is composed of several 

 factors. As in the postnatal development of a 

 life there are many potent factors, such as home The Factors ot 

 influences, associations, education, religious train- Defined. 

 ing, etc., each of which affects the life independent 

 of the others, the sum total of all forming the 

 character of the man; so in the prenatal forma- 

 tion of a soul there are many factors, each of 

 which exerts an influence peculiar to itself, the 

 combination of the whole determining the hered- 

 ity of the child. Now, iri order to simplify the 

 subject and bring the whole at once within the 

 grasp of the student, I shall endeavor to reduce 

 each of the several factors of heredity to a definite 

 statement, and explain, in brief, their co-operate 

 action. 



The twelve fundamental propositions or factors 

 of heredity and prenatal culture, as we shall study 

 them, are: 



1. SPECIES Or, that factory of heredity that (J) Species 

 comes to all men in common as members of the 

 species homo, and gives to each individual the 



basis of his physical and mental constitution. 



2. RACIAL TYPES Or, the factor of racial (2) Racial 

 peculiarities, which modify species, differentiate^ 7 **** 

 the several branches of the human family one 



