actically all of the improvements in
plants and animals have been brought about. This law may be explained as
follows: A certain kind of pure bred fowl is found which is either pure
white or black. If either color is mated with its own color the resulting
progeny will be true to the color of the parents, but if a white and a
black are crossed the result will be blue fowls possessing one-half the
characteristics of each parent, but strange to say, if two blue fowls are
mated the progeny will not be all blue, one-fourth will be white like one
grandparent, another one-fourth black like the other grandparent, and
one-half will be blue like the parents. If this experiment is repeated with
plants and animals having opposite characteristics, the same ratios as
above always result. This indicates that truly heritable traits or
characters are separate units and are inherited independently. The breeder
is thus enabled through selecting the traits or characters that are wanted
and crossing them with a well-known stock, to produce almost any trait or
quality that he desires. This law makes it possible to estimate the results
of cross breeding with almost mathematical exactness. Improved varieties of
fruits, grains and vegetables have been produced in this manner, and with
animals marvelous results have been achieved.

Luther Burbank, in his little book, "The Training of the Human Plant,"
says: "There is not a single desirable attribute which, lacking in a
plant, may not be bred into it. Choose what improvement you wish in a
flower, a fruit, or a tree, and by crossing, selection, cultivation and
persistence, you can fix this desirable trait irrevocably." And further:
"If then we could have twelve families under ideal conditions where these
principles could be carried out unswervingly, we could accomplish more for
the race in ten generations than can now be accomplished in a hundred
thousand years. Ten generations of human life should be ample to fix any
desired attribute. This is absolutely clear, there is neither theory nor
speculation."

_Acquirements of parents_ during their lifetime, according to the best
authorities, are not transmitted to any noticeable extent to their
children. This appears to be due to the fact that the cells concerned in
reproduction are set aside during embryonic life and from then on are
practically unmodified by the succeeding development and experiences of the
parent. In fact, during the lifetime of the