. THE FIRST BOOK OF BOTANY. 



EXERCISE III. 

 Venation. 



VENA'TION. The lines seen upon the leaf-blade 

 are called its venation. 



Hold up a leaf between your eye and the light, 

 and, if you see a net-work of irregular lines, it is a 

 net-veined leaf ; but, if you see no such net-work, as 

 in Fig. 4, it is a parallel-veined leaf. 



FIG. 3. 



FIG. 4. 



A Net-veined Leaf. 



A Parallel-veined Leaf. 



LOOKING AND OBSERVING. There are plenty of 

 boys and girls who have always lived in a garden, 

 and yet, if you asked them the difference between a 

 potato-leaf and a bean-leaf, they could not tell you. 

 They have looked at potato-plants and bean-plants 

 often enough, but they have never observed them. 



