LEAF-FORMS AND FIGURES. 



17 



16. In the next four kinds of leaves you will notice that 

 the broadest place is midway between the base and apex. 

 Thus the orbicular (Fig. 14), or rounded, leaf is about as 

 broad as it is long. The oval leaf (Fig. 15) is about one-third 

 longer than broad. This Plum leaf is an example. The el- 

 liptical (Fig. 16) is about twice longer than broad, and the 

 oUong (Fig. 17) is three or four times longer than broad. 

 Here are examples. 



Fig. 14. Orbicular leaf of Winter-green {Pyrola). 

 Fig. 15. Oval leaf of the Plum-tree. 

 Fig. 16. Elliptical leaf of Black Haw. 

 Fig. 17. Oblong leaf of a Willow. 



17. We next have four varieties of forms which are broader 

 towards the apex than base. First, the obovate (Fig. 18), 

 like this leaf of the Smoke-tree. Its outline is like tliat of 



16. Wlien is the figure of a leaf called orbicular? Will you show mo 

 specimens ? Describe an oval leaf, and give specimens. Describe an ellip 

 tical leaf, and give examples. Describe an oblong leaf, and give examples. 



17. When will the figure of a leaf become obovate ? Give examples of 



