THE PLANT BODY 



41 



pound leaf in palms. The major veins of the blade extend pinnately or 

 palmately from a midrib or basal area, distally running parallel with 

 the margin, and the lowermost veins form a narrow, strongly vascular 

 band along the margin of the blade (Fig. 20). The early ridges and 

 later folds do not extend into this band. When the folds are separated, 



Fig. 19. Sketches of transverse sections of young leaves showing pinnate and palmate 

 development, reins R at margins of blades. A, Roijstonia regki, a pinnate type, rachis 

 below developing pinnae; B, Livistona chincmis, a palmate type, hastula above 

 united with dorsal crest (lobe of rachis) below. {From Eames, 1953.) 



Fig. 20. Diagrams showing details of reins and hook in palm leaves. A, showing 

 lines of abscission and relation of reins and hook to blade; B, showing course of 

 vascular bundles and lines of abscission between pinnae and between pinnae and 

 rein, h, hook; r, rein. (From Eames, 1953.) 



