69 



CHAPTER VIII. 



STRUCTURE AND FUNCTIONS OF LEAVES. 



When a leaf is perfectly complete, it consists of three parts : — 

 I. The flat expanded portion which is popularly called the leaf. 

 This is the lamina, or blade. 2. The stalk, which attaches 



Fig. ioi.— Oval le.if of the 

 .^ppl-*, with two free .sti- 

 pules. 



Fig. 102.— Sessile leaves of Shepherd' s- 

 purse {Cafsella hirsn-yiastoris). 



this to the stem, the petiole or leaf-stalk. 3. The little leaf- 

 like projections at the point of union between the petiole and 

 the stem, the stipules. 



