40 THE HUMAN SIDE OF TREES 



future root, a plumule or incipient stem and a vast 

 quantity, comparatively, of food material. This 

 is in the form of cotyledons or fleshy leaves. They 

 are nearly always two in number which classes most 

 trees among the dicotyledonous nlants. A few 

 trees have monocotyledonous seeds. This would 

 be an unimportant distinction in itself, were it not 

 that these facts foretell certain styles of structure 

 and growth. 



Tree-seeds which have left their parent tree in 

 the fall, remain quiescent all winter, usually a few 

 inches below the surface of the ground. Under the 

 quickening influence of spring latent life stirs 

 within them. Their entire bodies are covered with 

 tight little water-proof jackets. Their only com- 

 munication with the outside world is through a 

 little window or door called the micropyle, which 

 means in Greek "small mouth." Therefore, their 

 first action is to drink in large quantities of water 

 through this micropyle. This makes them swell 

 prodigiously and eventually burst their enclosing 

 walls. In the meantime, the radicle, feeding on the 

 starch stored in the cotyledons, has passed out 

 through the micropyle and started on a downward 

 search for nourishment. With the seed-walls burst, 

 the little plumule, often with a tiny leaf already 

 developing, pushes its way to the surface. Some- 



