Seed-Carriers 265 



distance before eating them ; and if meantime their 

 attention be caught by something else, they will prob- 

 ably drop and forget all about them. Brazil-nuts, 

 for instance, are enclosed in such a very hard, strong 

 outer case that no monkey can get at the contents, 

 except by hammering it for a long time against a rock, 

 or a hard log of wood, neither of which is always to 

 be found close at hand. 



So much, then, for the voluntary carriers, whose 

 work is but small and limited, compared with that 

 of the great army of involuntary carriers. 



Look, for example, at a dog when he has been 

 hunting in a ditch, and see how the burdocks and 

 goose-grass, or cleavers, have taken advantage of him, 

 and made him act as carrier for them. Their fruits 

 are thickly set with tiny hooks, and with these they 

 have laid hold of his coat, entangling themselves in it, 

 and holding so tight, that though he may roll and 

 bite, and try in every way to rid himself of them, 

 he will often carry some about with him for days ; 

 and if on some long expedition, might travel a good 

 many miles before he had freed himself from them 

 all. ' 



Now, what is true of the dog in this respect is true 

 also of many animals, wild and domestic, including man 

 himself. The fleece of sheep, the fur and hair of other 

 animals, the feathers of birds, the clothes of human 

 beings all answer the purpose of these hooked, barbed 

 and thorny fruits, by giving them something which 

 they can lay hold of. No doubt we have all noticed 

 the extraordinary way in which the seeds of the wild 

 barley work their way into one's garments, and remain 

 for months unless picked out The seeds of the porcu- 



