Art Oui-of-Doors 



stem, the hickory an elongated oval, the 

 sugar-maple a much fuller oval, the white 

 birch a very long and slender oval, and the 

 oak a figure approaching more nearly to a 

 circle. In other cases the form of the head 

 is more irregular, as with the silver-maple, 

 for instance, the typical shape of which 

 would be expressed by a diagram of broken 

 outline. But even in such cases this shape 

 may easily be imprinted upon the memory, 

 and, once imprinted, the pleasure of looking 

 upon a new specimen of the tree is greatly 

 increased by one's knowledge of how nearly 

 it coincides with the typical form of the 

 species to which it belongs, or how far it 

 departs from it. 



But a tree's general outline is by no means 

 the only thing which determines its form. 

 Its structure is of almost more importance 

 than its outline, as this may be greatly af- 

 fected by position, accident, or man's inter- 

 ference, while, within very narrow limits, its 

 structure must always be the same. Branches 

 now droop stiffly like those of the spruce, 

 and now gracefully like those of the elm, or 

 they spread at right angles as in the cedar of 

 244 



