258 PLANT-LIFE 



with absorptive root-hairs. It is evident that such a 

 root requires a good deal of water, and is adapted to 

 deal with it in the limited area of its central and vertical 

 position. The leaves are beautifully constructed, and 

 arranged to meet the requirements of the roots. Their 

 stalks converge to a common centre, and are deeply 

 channelled on their upper surface. The broad blades 

 constitute a considerable water-collecting area, and their 

 venation is such that water is conducted by side or 

 tributary channels to the main channel, and thence 

 along the deeply channelled stalk to the common centre, 

 the top of the root stock. The leaves are placed at an 

 angle which insures that the great bulk of the rain- 

 water falling upon them shall be conducted by their 

 natural gutter system to the central position, where it 

 is in great demand. The Rhubarb plant is another 

 example of the same centripetal conduction of water, 

 and so also are the Parsnip and the Carrot. 



We take shelter under a Sycamore or a Chestnut-tree 

 during a shower of rain, knowing that but little of the 

 water will reach us; but we can watch the raindrops 

 falling from the leaves in a circle about us; and while 

 we are waiting and thinking, we may realize that the 

 water is reaching and saturating a circle of ground 

 occupied by the finer ramifications, furnished with root- 

 hairs, of the spreading roots. The " spreading chestnut- 

 tree " of the Village Blacksmith has a spread of roots 

 extending to an equality with the spread of the leafy 

 branches. The roots, indeed, reach out to the circle of 

 earth moistened by the " drip " from the leaves, and the 

 water falls just where it is in special demand by the roots. 



The leaves of a Sycamore or a Chestnut have a con- 



