TREES THAT TRAVEL 127 



seats, and by burs and prickles retain a precarious 

 hold on bird or animal. It is quite evident that the 

 spikes of the chestnut and the sharp hairs of the 

 beech are intended more for protection than trans- 

 portation. All those trees which bear attractive 

 and luscious fruit are contemplating a journey in 

 the dark but safe coach of crop or stomach. Their 

 colours are legion and very brilliant and usually 

 so planned as to contrast strikingly with the green 

 foliage. When the bird or animal has yielded to 

 the allurement of rosy skin and juicy pulp, the 

 seed's trip is begun and it can try to imagine just 

 where its unconsciously obliging vehicle will carry 

 it. The embryo trees are all specially equipped for 

 their sojourn in their host's digestive tract. In the 

 orange they are hard and bitter and have a gluti- 

 nous coating which makes them slippery and sure 

 of being swallowed whole. Plum, peach, and cherry 

 stones have coverings hard enough to defy the 

 strongest teeth. The protection in apples and 

 pears is not so good, though the tough coating is 

 often rejected and so escapes digestive incarcera- 

 tion entirely. 



Nuts also prefer the outside route. In fact, they 

 have everything to lose by being eaten. The all- 

 important germ of life is contained in the edible 

 matter. It would seem to be a case of nature sac- 



