48 Development and Distribution of Vegetation. 
into one mass. The stem is the end of a branch, bearing this whorl of leaves. 
This does not, however, tell the whole story. If we examine the cross-sec- 
tion of our apple more attentively, we see other green points, less distinct than 
the ten described. In the blossom the petals stand on the inside upper portion 
of the outside circle of five leaves. These latter constitute the calyx of the 
flowers. In the process of modification the petals — originally leaves and dis- 
tinct from the calyx leaves have been joined with the latter to near their top. 
The only remains of the lower united portion of the petal-leaves are the 
minute green lines to which attention has last been called. Really, then, an 
apple consists of more than ten leaves, but the ten form by far the greater 
portion of the fruit-substance. 
When we eat an apple we eat a cluster of leaves wondrously modified for 
the very purpose of being consumed by some animal whose tastes prompt the 
act. The fine flavor is a stimulus in this direction. The hard parts surround- 
ing the seed are for the protection of the latter, while mastication proceeds. 
Is it hard to see how a plant gains by having its seeds swallowed by an ani- 
mal? If uncrushed they pass the gauntlet of the digestive apparatus un- 
hurt, and well fitted for germination. Wide dissemination results, the very © 
thing required for the abundant multiplication of the species. Apples were 
made to eat, the seeds to be thrown away, and as far as practicable from their 
place of growth. 
Similar studies upon other fruits bring us to similar conclusions. Every 
one knows a strawberry plant by sight. Another native plant, growing wild 
in grassy fields, is familiarly called the barren “strawberry” (Potentilla). The 
two plants are indeed very much alike in leaf and flower, and, with one im- 
portant exception, in fruit also. They are so far as we can see equally hardy 
and thrifty. But the usual numbers of the real strawberry plants along any 
fence row or headland is far in excess of that of the barren strawberry. Why? 
The end of the fruiting stem of the former has gained the habit of swelling 
up into a deliciously flavored highly colored thing we inappropriately call a 
berry. The true fruits are the little seed-like, hard nutlets studding the sur- 
face of the pulpy mass. Each one of these is an ovary formed from a modi- 
fied leaf, producing within one seed. These latter are swallowed uninjured 
through the temptations offered by the glorified tip of the stem. Abundant 
dissemination results; while to the barren strawberry no such aid is coutrib- 
uted. The two plants are certainly near relatives, but one has gained an im- 
portant advantage over the other, and bids fair to keep it. There are no facts 
to which direct appeal can be made; but it is nevertheless almost certain that 
there were barren strawberry plants before there were what we call true straw- 
berries. The little dry fruits were borne upon a dry stem, before they were 
upon a fleshy one. 
In such matters, what transformations have been wrought by cultivation! 
The strawberry itself has been changed almost as much by art as just now 
indicated by nature. Our Ben Davis and Yellow Belleflower apples are far 
different from the hard and sour crabapples of the wild trees. See what a bud 
may become in the cabbage ‘‘head”’! In the ordinary cabbage it is the ter- 
minal bud that assumes such monstrous proportions; in the case of Brussels 
sprouts eight or ten of the lateral buds thickened instead, forming a cluster of © 
heads on the side of the stem; in Kohl-rabi the stem itself is swollen, like a 
turnip growing above ground; while all the buds are of normal size. Now 
all of these garden varieties when left in mild climates to run wild degenerate 
to the same, worthless colewort, showing their original identity. 
Look over a seedman’s catalogue and see the variety of new things in the 
way of vegetables and flowers. After making all allowance for the overdraw- 
ing of the pictures and descriptions, what a lesson may be learned upon the 
‘“‘metamorphoses of plants”! When these cultured varieties are compared 
