PLATE XXX. DIAGRAMS OF WOOD CHARACTERS. A, (a) procumbent ray cells in radial 

 view; (b) upright ray cells in radial view. B, (a) simple perforation plate; (b) scalariform 

 perforation plate. C, (a) procumbent ray cells in tangential view; (b) upright ray cells in 

 tangential view, D, (a) cross or transverse view; (b) radial view; (c) tangential view. 

 E, xylem elements as seen in cross view: (a) vessel; (b) axial parenchyma; (c) ray paren- 

 chyma; (d) tracheid; (e) fiber. 



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