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General Botany 



Fig. 272. Four species of oak: A, white oak {Quercus alba) ; B, bur oak {Quercus macro- 

 car pa) ; C, red oak {Quercus rubra); and D, pin oak {Quercus palustris). Note that the 

 species differ in shape of leaves and in size and form of acorns, but that they have many 

 characters in common. {After E. L. Moseley.) 



black oak, blue oak, red oak, live oak, all differing from each 

 other and from other oaks. 



Common names are quite satisfactory for ordinary purposes 



