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said, that the destiny of the world, as regards not only peas and 
people, but all forms of life, is wrapped up in the shuffling of these 
tiny bits of organic matter and the infinitesimally smaller particles 
which they transport. Though they are the cards in the game of 
life, they themselves are ruled by the laws of chance. 
As a penny falls heads or tails, so are the hereditary materials 
of both peas and people shuffled into new combinations that re- 
sult in a new pea or a new person. Each has its being and does 
what it does, in part, because of a fortunate or unfortunate com- 
bination of hereditary materials which it gets from its parents. 
To have good peas, a good inheritance is the first prerequisite, 
then the best of environments. So it is with people. 
True-breeding, brown-eyed races of peas very rarely have other 
than brown-eyed offspring. Likewise, white-eyed races give rise 
to white-eyed progeny. But cross a brown-eyed race with a white- 
eyed race and what results? The offspring are all brown-eyed, 
though they had a white-eyed as well as a brown-eyed parent. 
But cross or mate two of these brown-eyed hybrid offspring and 
what happens? Their progeny consists of both brown-eyed and 
white-eyed plants in the proportions of three brown-eyed to one 
white-eyed. Thus the generation in peas corresponding to the 
grandchild generation in human beings consists of plants with the 
same characters in respect to eye-color as the grandparents, in 
spite of the fact that the parents were both brown-eyed. 
Let us follow our pedigreed pea family through another genera- 
tion of its genealogy, and see what the fates bring forth. The 
white-eyed plants have only white-eyed offspring, and will con- 
tinue to do so indefinitely as long as only white-eye is mated with 
white-eye. Yet two of their ancestors were brown-eyed. 
Now as to those with brown eyes. One third breed true, and 
like the white-eyed offspring, will breed true to brown eyes in- 
definitely, despite their white-eyed ancestor. But two thirds of 
these third hybrid generation brown-eyed plants will again, as in 
the second generation, have both brown and white-eyed plants in 
the ratio of three to one. 
This illustrates one of the laws of heredity—the law of segrega- 
tion. Brown-eye and white-eye are a pair of characters differ- 
entiating two varieties of pea plants. Each variety has its heredi- 
