elevated to the highest rank, as a measure of the hereditary qualities.
Henceforward we will designate it by the name of hereditary percentage.

In scientific experiments this figure must be determined for every plant
of a pedigree-culture singly, and the selection should be founded
exclusively or at least mainly on it. It is easily seen that this method
requires large numbers of individuals to be grown and counted. Some two
or three hundred progeny of one plant are needed to give the decisive
figure for this one [415] individual, and selection requires the
comparison of at least fifty or more individuals. This brings the total
amount of specimens to be counted up to some tens of thousands. In
practice, where important interests depend upon the experiments, such
numbers are usually employed and often exceeded, but for the culture of
monstrosities, other methods are to be sought in order to avoid these
difficulties.

The idea suggests itself here that the younger the plants are, when
showing their distinguishing marks, the more of them may be grown on a
small space. Hence the best way is to choose such attributes, as may
already be seen in the young seedlings, in the very first few weeks of
their lives. Fortunately the seed-leaves themselves afford such
distinctive marks, and by this means the plants may be counted in the
pans, requiring no culture at all in the garden. Only the selected
individuals need be grown to ripen their seeds, and the whole selection
may be made in the spring, in the glasshouse. Instead of being very
troublesome, the determination of the hereditary percentages becomes a
definite reduction of the size of the experiments. Moreover it may
easily be effected by any one who cares for experimental studies, but
has not the means required for cultures on a larger scale. And lastly,
there are [416] a number of questions about heredity, periodicity,