I.] BOTANY. 



leaves, flowers, and fruit; 3. The Leaves, which are 

 usually thin and so placed as to receive as much 

 light as possible upon one surface ; 4. The assem- 

 blage of organs called the Flower; a part of this 

 grows into the Fruit, which contains the Seeds. 



The purposes which organs are specially fitted to 

 serve are called their Functions. The most im- 

 portant of these in all plants are nourishment and 

 reproduction. Plants have no organs of locomotion, 

 or of the senses. 



In Flowering Plants Nourishment is effected 

 by means of the root and leaves. Unlike animals, 

 such plants have no special stomach to receive the 

 food, no heart or blood-vessels to distribute it, and 

 no special organs to carry off what is not used as 

 nutriment. 



The Food of plants is liquid and gaseous, never 

 solid. The root absorbs water, in which both gaseous 

 and mineral matters are dissolved ; and this fluid 

 ascends and enters the leaves, which also take in 

 carbonic acid gas from the air. By the action of 

 light on the water and carbonic acid in the leaves a 

 substance called Starch is formed, which is distri- 

 buted throughout the plant, supplying in great mea- 

 sure the material for adding to its parts. 



The excess of water taken up by the root is ex- 

 haled by the leaves, and this tends to keep them cool. 

 From the starch produced in the leaves and nitro- 

 genous compounds taken up by the roots and dissolved 

 in the fluids which permeate the plant, albuminoids 

 are formed, which are very essential in producing 

 growth. These fluids further supply the materials 

 from which are manufactured by the plant various 



