A LIST OF THE TREES AND SHRUBS OF 



OKLAH( IMA. 



Sub-kingdom SPERMATOPHYTA, 



SEED-BEARING PLANTS. 



CLASS I. GYMNOSPERMAE. 



NAKED SEEDS. 



The Gymnosperms are an ancient group of plants. They are 

 found among the fossils of the Silurian age, and are most numei 

 in Triassic time. They are new repersented by about 450 species 

 trees and shrubs. They are flowering plants in which the ovules. 

 s, are not inclosed in an ovary, but are borne naked upon ail 

 open scale. This scale is a modified leaf. The plants have a resin- 

 ous juice, and chiefly parallel-veined, needle-shaped, or scale-like 

 evergreen leaves. By tar the larger number of the Gymnosperms 

 are Coniferous (Pinaceae or Coniferae including some shrubs 

 cone-bearing tree-, the fruit being called a cone because of its form. 

 This family of the class is the only one represented in our area. 



PINE FAMILY. PINACEAE. 



PINES. CONIFERS 

 Pin 



The tree- belonging t«> this family are commonly known as Ever- 

 ns, because with the exception of the Larch and the Bald Cy- 

 press they do n< t shed their leaves during the winter. The Line- 

 are a survival from the Devonian age. They were contemporaries 

 of the Lycopods, the Sigillarids, and the Cycads which constitute the 

 chief remaii - md in the coal measure formations. 



The Line- -till retain the simplicity of floral structure which was 

 characteristic of the vegetation of early times. The fertilization of 

 these tree- depends upon the wind. 



