98 



LEAVES AND FOLIAGE 



called stipels. The leaf of the garden bean has leaflets, 

 petiolules, and stiples. 



209. The blade is usually attached to the 

 petiole by its lower edge. In pinnate-veined 

 leaves, the petiole seems to continue through 

 the leaf as a midrib (Fig. 138). In some 

 plants, however, the petiole 

 joins the blade inside or be- 

 yond the margin (Fig. 140). 

 Such leaves are said to be 

 peltate or shield-shaped. This 

 mode of attachment is par- 

 ticularly common in floating 

 leaves (e.g., the water-lilies), 

 us. Compile leaves 146. Clasping Fe'af Peltate 1 e a v e s are usually 

 of willow. of wild aster. c iigi ta te-veined. 



210. Shape. — Leaves and leaflets are infinitely variable 

 in shape. Names have been given to some of the more 

 definite or regular shapes. These names are a part of the 

 language of botany. They represent ideal or typical shapes, 

 but there are no two leaves alike and very few that perfectly 

 conform to the definitions. The shapes are likened to those 

 of familiar objects or of geometrical figures: 

 Linear, several times longer than broad, with the sides 



\ nearly or quite parallel. Spruces and most grasses 

 are examples. (Fig. 150.) In linear leaves, the main 

 veins are usually parallel to the midrib. 

 Oblong, twice or thrice as long as broad, with the sides 



% parallel for most of their length. Fig. 149 shows the 

 short-oblong leaves of the box, a plant which is much 

 used for edgings in gardens. 

 Elliptic differs from the oblong in having the sides gradu- 



Vally tapering to either end from the middle. The Eu- 

 ropean beech (Fig. 151) has elliptic leaves. (This tree 

 is often planted.) 



