FORMS AND FIGURES OF LEAVES. 



15 



Climbing Fern (Fig. 6). To say nothing of the live veins 

 (which are palmate, as in the leaves of Sweet-gum, Fig. 4 a), 

 you may notice the veinlets, how they fork and run to the 

 margin, without uniting again to form a net-work. This is 

 the forked venation. You will lind this sort in nearly all 

 tlie Ferns. 



LESSON IJI. 



FORMS AND FIGURES OF LEAVES. 



13. You have already noticed that the form of the Quince 

 leaf, and of most others, is a thin, flat expansion, presenting 

 a large surface to the air. A few plants have thick, solid 

 leaves, as the leaves of the Live-forevers and Ice-plants. 



Fig. 7. Represents a branch of Juniper, with awl-sliaped leaves (subulate). 

 Fig. 8. Leaves of the Fleur-de-lis (Iris) ; they are sword-shaped (ensiform). 

 Fig. 9. Leaves of the Scotch Pine; they are needle-shaped (acerose). 



Other plants have slender leaves, as the Pines. See Figs. 

 T, 8, and 9. 



13. What is the general form of leaves ? What plants have thick and 

 solid leaves? What form of leaves has the Pine? the Iris? the Juniper? 



