136 BRITISH PLANTS 
reject the seeds. This serves the plant very well, for the 
result is the distribution of the seed. 
(a) Fruits.—Before the seeds are ready for dispersal, the © 
ripening fruits must be protected against weather, against 
disease, and against the chances of being prematurely 
eaten and destroyed. This is secured in various ways. 
Many succulent fruits contain antiseptic oils, aromatic or 
bitter principles, or similar substances equally unpleasant 
to animals searching for food, and germs that might 
destroy. Unripe fruits are hard, sour, unattractive, and 
unpalatable. Some have a bitter rind like the orange, 
others are covered by a coating of wax, others are fur- 
nished with disagreeable hairs, and others are defended 
by an armour of spines. 
Among succulent fruits we have the stone-fruit, or drupe 
—e.g., peach—and the soft-fruit, or berry—e.g., grape. 
In the drupe the fleshy part is eaten by birds, and the 
stone containing the seed is rejected. To keep the fruit 
from drying up before the seeds are ripe, as well as 
to keep off external water, the outside is protected by 
a dense elastic skin, frequently covered over with wax or 
“bloom ”’—e.g., plum. This wax is antiseptic, and pre- 
serves the fruit against the attack of fungi and bacteria, 
which would cause it to go rotten before it is ripe enough 
to attract the birds. It is important, therefore, that the 
continuity of the skin should be kept intact, since wounds 
and abrasions lay bare the deeper unprotected tissues, and 
expose them to disease. In the berry the whole fruit is 
fleshy, but the seeds are hard and indigestible. Even if they 
are swallowed by birds, the seeds pass uninjured through 
their bodies. Some berries—e.g., deadly nightshade—are 
poisonous, and can only be eaten with impunity by a few 
birds which have become constitutionally used to them. 
Nuts have either tough leathery shells or hard stony 
cases. These prevent the seeds from being eaten except 
by those animals whose teeth are strong enough to open 
the shells, and which alone are capable of effectively dis- 
tributing the contents. At the same time some means 
are always adopted to protect the nuts while they are 
young and tender. In some cases the sepals enlarge and 
envelop them. In the acorn and hazel, bracts coalesce and 
form cupules (Fig. 47); in the beech and chestnut they “ 
form spiny shells (Fig. 48). 
