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special protection of poison, prickles, etc., or which can creep along the 

 earth within a half -inch limit. Even of this minority most are exterminated 

 where grazing animals are numerous, by being trampled upon or 

 accidentaly bitten off and discarded. Only the grass has, so to speak, 

 studied the needs of the grazing animal in order to supply them to its 

 own advantage. It produces no stem to be trampled upon or bitten 

 through, but from its mat of fibrous roots sends up innumerable tiny ribbons 

 of wholesome green food. When these are bitten to within half-an-inch 

 of the ground, it pays out another half-inch of each growing ribbon in 

 readiness for the animal's next visit. So it goes on, until the grass, in its 

 own brief fruiting season, quickly sends up a comparatively stiff and wiry 

 stalk with scaly and chaffy inflorescence, which the grazing animal prefers 

 not to eat since tender blades of grass are still to be had in abundance. 

 Thus enough grass seed survives to spread the race more widely and 

 provide sustenance for larger herds. From this and the previous examples 

 quoted we learn the true secret of nature in the inevitable triumph of those 

 animal and vegetable allies which are mutually helpful to one another. 



I should say that the " alliance " between grass and grazing 

 animal does not represent a particularly high form of Symbiosis ; 

 the example, however, may serve to illustrate the application 

 of the principle of biological remuneration, though the 

 "remunerated" are otherwise " plant-carnivora," and pro 

 tanto marked by backwardness of evolution. 



Again in " Country-Side Leaflet," Jan., 1918, Mr. K. Robinson 

 states the following : 



There is no week in the country without its little harvest for the wild 

 things, and just now it would seem as if word had been passed round that 

 the acorns of the holm oak are really ripe at last ; because scores of fat 

 wood-pigeons are marching about under the trees in the park, gulping and 

 choking as they go, in the effort to make room for just one more. Forty 

 of these small acorns are only a moderate load for the wood-pigeon to 

 cram into its crop ; and indirectly it does some good by its greediness, 

 because when it has flown home at dusk to roost in the pinewood, it is very 

 sick and throws up, or rather throws down, some of the acorns upon the 

 ground below. This is why young oak trees, both of the common and 

 evergreen kinds, are always springing up under the pine trees, so that 

 the pine wood which you knew as a boy is very often an oak wood when 

 you revisit it as a man. 



In the same way and from the same cause, the beech often succeeds 

 the pine, because the wood-pigeon finds a surfeit of beech nuts very diffi- 

 cult to keep. Solitary oaks growing in the open, on the other hand, are 

 generally the work of rooks which have buried acorns that they could not 

 eat, and have never found them again ; while it is largely to the squirrel 

 that we are indebted for the abundant growth of oak and hazel in our 

 woodlands. He was busy all through the autumn days, scampering about 

 and hurriedly burying acorns and nuts, of which he probably does not 

 discover fifty per cent, afterwards. 



