LIFE HISTORIES OF FAMILIAR PLANTS 



ends of the branches developed thorns, and that 

 the device proved so effective that later the indi- 

 vidual leaves each acquired a protective point, the 

 tissues of which hardened at the expense of the 

 substance of the leaflets until it had absorbed them 

 and developed into a stout thorn. 



Thus, there is ample reason to suppose that the 

 now unassailable gorse was once a soft-leaved plant 

 whose leaves consisted of three leaflets, like other 

 members of its family, but that it was driven per- 

 force into arming itself against persistent animal at- 

 tacks, and so thoroughly did it carry out the work 

 that, to-day, it represents the most perfect example 

 of bayonet protection amongst British plants. 

 Consequently it can thrive on the open commons 

 and moors, with its most dangerous enemies ever 

 around it, but none of which now dare approach 

 to nibble at its branches. 



The gorse, like the broom, in seeking pro- 

 tection from animal attacks has had to reduce its 

 leaf area. Its branches and smaller thorns con- 

 sequently are green like the branches of the 

 broom. The green thorns, of course, represent 

 the leaves, and, together with the branches, they 

 carry on the functions of leaves. Also, it should 

 be observed that by thus hardening the leaves into 

 thorns, the gorse is enabled to do away with the 

 annual ^^fall" of its leaves in autumn, and so 

 becomes an evergi-een. Therefore, although its leaf 

 area is hmited, yet, in view of the fact that it can 

 absorb sunlight energy and gaseous food on every 

 bright day throughout the winter, while most 



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