LEAVES 



101 



possible from the end of the petiole, to 

 distribute water quickly throughout. 



118. Stipules Although they are 



absent from many leaves and disappear 

 early from others, stipules often form a part 

 (sometimes the largest and most useful por- 

 tion) of the leaf.i When present they are 

 sometimes found as little bristle-shaped 

 objects at the base of the leaf, as in the 

 apple leaf (Fig. 63), 



T 



Fig. 64. Leaf of 

 Pansy, with Leaf- 

 like Stipules. 



sometimes as leaf 

 like bodies, for ex- 

 ample in the pansy (Fig. 64), and in 

 many other forms, one of which is 

 that of spinous 

 appendages, as 

 shown in the 

 common locust 

 (Fig: 68). 



119. Parallel- 

 Veined Leaves. 

 — The leaves of 

 many great groups of plants, such as 

 the lilies, the sedges, and the grasses, 

 are commonly parallel-veined, that is, 

 with the veins running nearly par- 

 allel, lengthwise thi'ough the blade, 

 as shown in Fig. 65, or with parallel 



1 Unless the elin twigs used in the previous ^'.<'- ^^- Parallel Vein- 

 study were cut soon after .tie unfolding of the i^^S i" Canna. Veins 

 leaves in spring, the stipules may not have been running from midrii 

 left in any recognizable shape. to margin. 



Tig. 65. Parallel-Veined 

 Leaf of Solomon's Seal. 



