VI.] 



BROAD AND NARRO W LEA VES. 



133 



as throwing light on the reason why herbaceous plants 

 so often have their leaves much cut up. 1 



Next let me say a few words on the reasons why 

 some plants have broad and some narrow leaves. 

 Both are often found within the limits of a single 

 genus. I have ventured to indicate the distance 

 between the buds as a possible reason in certain 

 cases. It would not, however, apply to herbaceous 



FIG. 82. Senecio 



genera such as Plantago or Drosera. Now, Drosera 

 rotundifolia (Fig. 83) has the leaves nearly orbicular, 

 while in D. anglica (Fig. 84), they are long and narrow, 

 Plantago media (Fig. 85) has ovate leaves, while in 

 P. lanceolate (Fig. 86) they are lanceolate, and in 



1 Mr. Grant Allen, who had been also struck by the fact that 

 herbaceous plants so often have their leaves much cut up, has suggested 

 a different explanation, and thinks it is .due to "the fierce competition 

 that goes on for the carbon of the air between the small matted under- 

 growth of every thicket and hedgerow. " 



