THE LEAF AS A BUILDER. 



Not less plainly does the diversity of character in 

 a leaf reveal the diversity of tree life itself. No 

 two leaves are exactly alike ; no two 

 trees are exactly alike. There are spe- 

 cific as well as generic differ- 

 ences which are strongly 

 marked. One tree leads a 

 rugged, wild, and struggling 

 life ; another an easy, luxurious 

 life. The rough and fuzzy leaf 

 of the slip- 

 pery elm, the 

 silky leaf of 

 the beech, the 

 shiny leaf of 

 the gray birch, 

 these are all 

 widely differ- 

 ent ; but there are also dis- 

 tinct differences between 

 the leaves of different kinds 

 of birches, elms, and maples. 



Still, there are puzzling 

 similarities, and one is often 

 compelled to study minute 

 details in order to make sure 

 of a particular species. " The sUky leaf of the Beech " 



