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Bulletin of the University of Texas 



cms. ' ' The determination is then checked by turning to the de- 

 scription of the species and consulting the illustration. If the 

 pine is taken, the first choice goes to "leaves needle scale or awl- 



IV. Lobed Simple Leaves. 



Pinnately: 1. Lobed. 3. Cleft. 5. Parted. 7. Divided. 

 Paimateiy: 2. Lobed. 4. Cleft. 6. Parted. 8. Divided. 



shaped," etc., which leads to the family Pinaceae. Here the 

 decision is between ' ' leaves all needle-shaped ' ' and ' ' leaves scale- 

 like and appressed to the stem, or some of them awl-shaped, 

 spreading." If the leaves are needle-shaped and borne in clus- 

 ters of two to five, the species goes to the genus Pinus. 



It is believed that practice in the use of the key will soon 

 enable one to locate the family, genus, and species with almost 

 certain accuracy. It must be borne in mind that accuracy of 

 observation is necessary to its successful use. 



