THE MORPHOLOGICAL COMPOSITION OF PLANTS. 



29 



posing the plant to be a well-grown one, it will furnish all 

 gradations between the simple, very small leaf, and the large 

 composite leaf, containing sometimes even seven leaflets. 

 Figs. 50 to 64, represent leading stages of the transition. 



What determines this transition ? Observation shows that the 

 quintuple leaves occur where the materials for growth are 

 supplied in greatest abundance ; that the leaves become less 



