CHAPTER XIV 
HEREDITY AND GERMINAL CONTINUITY— 
MENDEL, GALTON, WEISMANN 
It is a matter of common observation that in the living 
world like tends to produce like. The offspring of plants, 
as well as of animals, resembles the parent, and among all 
organisms endowed with mind, the mental as well as the 
physical qualitics are inherited. This is a simple statement 
of the fact of heredity, but the scientific study of inheritance 
involves deep-seated biological questions that emerged late 
in the nineteenth century, and the subject is still in its 
infancy. 
In investigating this question, we need first, if possible, 
to locate the bearers of hereditary qualities within the physical 
substance that connects one generation with the next; then, 
to study their behavior during the transmission of life in order 
to account for the inheritance of both maternal and paternal 
qualities; and, lastly, to determine whether or not transiently 
acquired characteristics are inherited. 
Hereditary Qualities in the Germinal Elements.—When 
we take into consideration the fact established for all animals 
and plants (setting aside cases of budding and the division 
of unicellular organisms), that the only substance that passes 
from one generation to another is the egg and the sperm in 
animals, and their representatives in plants, we see that the 
first question is narrowed to these bodies. If all hereditary 
qualities are carried in the egg and the sperm—as it seems 
they must be—then it follows that these germinal clements, 
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