LABURNUM, BROOM, AND GORSE 



the young shoots appear above the ground they 

 are greedily nibbled down by rabbits and larger 

 animals. Therefore, on the open moors, where the 

 gorse has made its home, the development of a 

 prickl}^ armour was an absolute necessity. What 

 proof have we, however, that the gorse did really 

 possess trefoil leaves — like those of the broom or 

 laburnum — which characterise its family ? 



You have but to search around some gorse 

 bushes and find a seedling plant to get a complete 

 answer to that question. The young plant tells its 

 own story, for after its seed-leaves have appeared 

 above the soil they are quickly followed by trefoil 

 leaves, similar in form to those of the fully developed 

 broom. In Figs. 66 and 6y (Plate 45), the matter 

 is clearly explained. The lower leaves of the 

 young seedling will be seen to be three-foliolate. 

 As the stem develops, some of these leaves change 

 into three-parted spines, wdiile others lose two of 

 their leaflets, the central one remaining, as in the 

 upper leaves of the broom. Still higher up the 

 stem the leaflets get thinner and sharper, gradually 

 changing into thorns, as the upper example on 

 the right of Plate 45 well shows. 



Indeed, each young plant records in miniature 

 the whole evolution of its species, from its trefoil 

 stage until it has developed a complete armour of 

 thorns. Amongst the changing leaves appears, here 

 and there, a large thorn which has developed well 

 in advance of the leaves. Such thorns are the 

 modified early branches of the young plant, and 

 their appearance in this order tells us that first the 



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