vr COLOURS OF PLANTS 899 



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, umbelliferae, 

 etc., always have dry and obscurely coloured capsules and 



