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TEXTBOOK OF BOTANY 



veins. These larger veins are smallest at the apex and margin of the leaf 

 and gradually become larger toward the middle and base of the blade. 



Fig. 15. Arrangement of the larger veins. The leaves of magnolia (A) and tulip- 

 tree (B) exemplify pinnate venation; red bud (C) and black maple (D), palmate 

 venation. Veins may also be parallel as in the bamboo (F) or dichotomous as in the 

 ginkgo (E). From drawings by C. H. Otis, Mrs. A. E. Hoyle, and C. J. Cham- 

 berlain. Fig. E from Textbook of Botany (Coulter, Barnes, and Cowles), Amer. 

 Bk. Co. 



Fig. 16. The leaves of bitternut hickory and clammy locust are pinnately com- 

 pound (A-B). Those of Aralia and horse chestnut are palmately compound (C-D). 

 From drawings by Mrs. A. E. Hoyle and E. B. Wittlake. 



The arrangement of the veins of a leaf is termed venation. There are 

 four general arrangements of the principal veins in leaves that are easily 



