BOTANY. 



FIG. ii. 



FIG. 10. 



off veins right and left from its sides, it is said 

 to be feather-veined, or pinnately veined. But 

 when the petiole divides, at or near the base of 

 the blade, into sever- 

 al diverging ribs (Fig. 

 5), the leaf is said to 

 be radiate, or palmate- 

 veined. If the ribs of 

 a net-veined leaf con- 

 verge toward the apex, 

 as in Fig. 7, it forms 

 that variety of vena- 

 tion known as ribbed. 



Figs. 10 and n represent parallel-veined 

 leaves, in which the veins take the direction 

 seen in feather- veined and palmate -veined 

 leaves. But in this case there is no net-work of veinlets, 

 and so they are not net-veined. You will find many such 

 leaves connected by unbranched veinlets. Remember that 

 it is by the absence of this irregular network that you may 

 know parallel-veined leaves. See Fig. 38. 



Determine, in regard to all the leaves you can find, 

 whether they are net-veined or parallel-veined ; and 

 whether the net-veined ones are feather-veined or pal- 

 mate-veined. 



EXERCISE III. 

 Leaf-Margins. 



When the edge or margin of a leaf is smooth and even, 

 it is said to be entire (Fig. 7). When the margin is un- 

 even, with sharp teeth pointing toward the apex like the 

 teeth of a saw, the leaf is said to be serrate (Fig. 12) ; if 

 the teeth point toward the base, it is retroserrate ; if they 

 are themselves serrate, as shown in Fig. 13, , they are 

 said to be biserrate. When minutely serrate, they are 

 termed serrulate. 



