IL] A BUTTERCUP. n 



CHAPTER II. 



EXAMINATION OF A BUTTERCUP CONTINUED. 



1. The buttercup fades. Why? Experiment shows that it is 



because water is withheld. 



2. The root an absorbing organ. 



3. Water is exhaled from the leaves. Transpiration. Ab- 



sorption. 



4. Other substances, besides water, are absorbed. The ash and 



inorganic constituents of plants. 



5. The organic compounds of carbon, oxygen, hydrogen, and 



nitrogen. 



6. Ternary and quaternai-y compounds of these elements are in 



contrast. 



7. Source of carbon in carbonic acid. 



8. Liberation of oxygen by plants under the influence of sun- 



light. Assimilation. 



9. Source of nitrogen. 



10. Processes of absorption, transpiration, assimilation, and 

 respiration, performed by ' organs of nuti'ition, ' viz. the 

 root, stem, and leaves. 



i. T) Y this time the specimen of buttercup has probably 

 JL) faded ; the leaves, now become soft and flaccid, 

 are drooping, and the stem has lost much of its stiffness. 

 How is this? 



If the specimen be not quite withered, plant it again in 

 the soil, and cover it with a flower-pot, or, better and 

 more easily done, put the root in water, and place the 

 whole in a cool shaded place for a few hours. We shall 

 anticipate matters, and suppose that this has been already 

 done, and that you tried the experiment in this way upon 

 three distinct specimens of buttercup. No. i you left 



