528 
BIOLOGY AND HUMAN PROGRESS 
a crop of hay. Figure 435 shows the practical value of planting 
seed that yields a large crop instead of a small one. In each 
of the five bundles in this figure, the same amount of seed 
was planted in the same kind of soil. Here we have a 
variation in the quantity of hay. 
The amount of variation in living things is only partly 
appreciated, as complete studies have not been made. In a 
recent study of wheat a great deal of variation was noted, 
as is illustrated by Figure 436. Wheat is raised for the purpose 
of obtaining as large a yield as possible of wheat kernels. 
Figure 435 . — Bundles of Timothy Raised under Identical Conditions 
from the Same Amount of Seed. 
It pays to plant good seed. (Photograph furnished by Cornell University.) 
A farmer who planted seed that produced plants with short 
and thin heads would harvest from ten to fifteen bushels 
per acre; while the one that planted seed that grew plants 
from which twenty-five to thirty-five bushels per acre could 
be had would be more successful. 
In order to furnish the farmer with the necessary informa¬ 
tion upon all such subjects, scientific experts have been and 
are now devoting a great deal of time to experimentation. 
The following examples are given to show the importance 
of such studies in helping man to make plants grow as he 
wishes them to grow and thus control his environment. 
