90 FL IV ER- LAND. 



its sheath, or an umbrella from its case. So that 

 there are three chief parts of a leaf for you to remem- 

 ber the lamina, or blade ; the petiole, or stalk ; and 

 the sheath. Sometimes a leaf is not only without any 

 petioles as in the grass, or without any sheath as in the 

 ivy or violet, but it has neither petiole nor sheath 

 The blade arises immediately from the node, and so 

 because it sits as it were upon the stem, such a leaf 

 is described as sessile * (Fig. 56). 



* From the Latin " sessilis" sitting (sedco, I sit). 



