VI COLOURS OF PLANTS 399 
is not carried farther is probably because it is not needed, 
these trees producing such vast quantities of fruit, that, how- 
ever many are eaten, more than enough are always left to 
produce young plants. In the case of the attractively coloured 
fruits, it is curious to observe how the seeds are always of 
such a nature as to escape destruction when the fruit itself is 
eaten. They are generally very small and comparatively 
hard, as in the strawberry, gooseberry, and fig; if a little 
larger, as in the grape, they are still harder and less eatable ; 
in the fruit of the rose or (hip) they are disagreeably hairy ; 
in the orange tribe excessively bitter. When the seeds are 
larger, softer, and more eatable, they are protected by an 
excessively hard and stony covering, as in the plum and 
peach tribe; or they are enclosed in a tough horny core, as 
with crabs and apples. These last are much eaten by swine, 
and are probably crushed and swallowed without bruising 
the core or the seeds, which pass through their bodies 
undigested. These fruits may also be swallowed by some of 
the larger frugivorous birds, just as nutmegs are swallowed 
by pigeons for the sake of the mace which encloses the nut, 
and which by its brilliant red colour is an attraction as soon 
as the fruit has split open, which it does upon the tree. 
There is, however, one curious case of an attractively 
coloured seed which has no soft eatable covering. The Abrus 
precatoria, or “rosary bean,” is a leguminous shrub or small 
tree growing in many tropical countries, whose pods curl up 
and split open on the tree, displaying the brilliant red seeds 
within. It is very hard and glossy, and is said to be, as 
no doubt it is, “very indigestible.” It may be that birds, 
attracted by the bright colour of the seeds, swallow them, 
and that they pass through their bodies undigested, and so 
get dispersed. If so it would be a case among plants analo- 
gous to mimicry among animals—an appearance of edibility 
put on to deceive birds for the plant’s benefit. Perhaps it 
succeeds only with young and inexperienced birds, and it 
would have a better chance of success, because such deceptive 
appearances are very rare among plants. 
The smaller plants whose seeds simply drop upon the 
ground, as in the grasses, sedges, composites, umbellifere, 
etc., always have dry and obscurely coloured capsules and 
