eded, from the plant mother, the upper part of each
stile drops off, leaving a sharp, stiff hook at the end. At this time
each pistil loosens from the torus and can be easily removed,
especially if some animal touch the hooks. To help in holding fast
to animals, there are a number of slender hairs farther down the stile,
which are liable to become more or less entangled in the animal's
hair, fur, wool, or feathers. Even in the small number of plants here
noticed, we have seen that scarcely any two of them agree in the
details of their devices for securing transportation of seeds. I know
of nothing else like the Geum we are now considering. When young and
green, the tip of each hook is securely protected by a knob or bunch,
with a little arm extending above, which effectually prevents the
hook from catching on to anything; but, when the fruit is ripe, the
projecting knob with its little attachment disappears. The figures
make further description unnecessary. To keep the plow from cutting
into the ground while going to or from the field, the farmer often
places a wooden block, or "shoe," over the point and below the plow.
Sometimes we have known persons to place knobs of brass or wood on
the tips of the sharp horns of some of their most active or vicious
cattle, to prevent them from hooking their associates or the persons
having them in charge. Nature furnishes the points of the young fruits
of some species of Avens with knobs, or shoes, for another purpose,
to benefit the plants without reference to the likes or dislikes of
animals.

[Illustration: FIG. 56.--The pistil of Avens in three stages of its
growth.]

48. Diversity of devices in the rose family for seed sowing.--All
botanists now recognize plants as belonging to separate families,
the plants of each family having many points of structure in common.
Among these families of higher plants, over two hundred in number,
is one known as the rose family. Notwithstanding their close
relationship, the modes of seed dispersion are varied. The seeds of
plums and cherries and hawthorns are surrounded by a hard pit, or
stone, which protects the seeds, while animals eat the fleshy portion
of the fruit. When ripe, raspberries leave the dry receptacle and
look like miniature thimbles, while the blackberry is fleshy
throughout. The dry, seed-like fruits of the strawberry are carried
by birds that relish the red, fleshy, juicy apex of the flower stalk.

Each little fruit of so