46 



GENERAL PRINCIPLES. 



the well-being of the tree, are continually going on ; for 

 trees shut out from the light always make a feeble growth, 

 and have a blanched and sickly hue, compared with the 

 same species in the free air, and exposed to the rays of the 

 sun. If one side or portion of a tree is shaded or deprived 

 of its full share of light, it ceases to grow in its natural 

 way, and the shoots are lean, slender, and imperfect. 

 2d. Different Forms and Characters of Leaves. The 



Figs. 23 to 27. FORMS or LEAVES. 

 23, oval ; 24, oblong ; 25, lanceolate ; 26, ovate ; 27, obovate. 



different sizes and forms of the leaves of fruit trees, the 

 divisions of their edges, the absence or presence of glands, 

 the smoothness or roughness of their surfaces, are all, 

 more or less, serviceable in describing and identifying 

 varieties. 



The terms designating forms are seldom mathemati- 



